bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pseudoknot-Dependent Translational Coupling inrepBAGenes of the IncB Plasmid pMU720 Involves Reinitiation
Authors: Praszkier J. , Pittard A. J. 
Published: September 2002

ABSTRACTReplication of the IncB miniplasmid pMU720 requires synthesis of the replication initiator protein, RepA, whose translation is coupled to that of a leader peptide, RepB. The unusual feature of this system is that translational coupling inrepBAhas to be activated by the formation of a pseudoknot immediately upstream of therepAShine-Dalgarno sequence. A small antisense RNA, RNAI, controls replication of pMU720 by interacting withrepBAmRNA to inhibit expression ofrepAboth directly, by preventing formation of the pseudoknot, and indirectly, by inhibiting translation ofrepB. The mechanism of translational coupling inrepBAwas investigated using the specialized ribosome system, which directs a subpopulation of ribosomes that carry an altered anti-Shine-Dalgarno sequence to translate mRNA molecules whose Shine-Dalgarno sequences have been altered to be complementary to the mutant anti-Shine-Dalgarno sequence. Our data indicate that translation ofrepAinvolves reinitiation by the ribosome that has terminated translation ofrepB. The role of the pseudoknot in this process and its effect on the control of copy number in pMU720 are discussed.
The Positive Regulator, TraJ, of the
Escherichia coli
F Plasmid Is Unstable in a
cpxA
* Background
Authors: Gubbins Michael J. , Lau Isabella , Will William R. , Manchak Janet M. , Raivio Tracy L. , Frost Laura S. 
Published: September 2002

ABSTRACT

The Cpx (conjugative plasmid expression) stress response of
Escherichia coli
is induced in response to extracytoplasmic signals generated in the cell envelope, such as misfolded proteins in the periplasm. Detection of stress is mediated by the membrane-bound histidine kinase, CpxA. Signaling of the response regulator CpxR by activated CpxA results in the expression of several factors required for responding to cell envelope stress. CpxA was originally thought to be required for the expression of the positive regulator of the F plasmid transfer (
tra
) operon, TraJ. It was later determined that constitutive gain-of-function mutations in
cpxA
led to activation of the Cpx envelope stress response and decreased TraJ expression. In order to determine the nature of the downregulation of TraJ, the level of expression of TraJ, TraM, and TraY, the F-encoded regulatory proteins of the F
tra
region, was determined both in a
cpxA
* background and in a wild-type background in which the Cpx stress response was induced by overexpression of the outer membrane lipoprotein, NlpE. Our results suggest that TraJ downregulation is controlled by a posttranscriptional mechanism that operates in the cytoplasm in response to upregulation of the Cpx stress response by both the
cpxA
* gain-of-function mutation and the overexpression of NlpE.
Conserved Response Regulator CtrA and IHF Binding Sites in the α-Proteobacteria
Caulobacter crescentus
and
Rickettsia prowazekii
Chromosomal Replication Origins
Authors: Brassinga Ann Karen C. , Siam Rania , McSween William , Winkler Herbert , Wood David , Marczynski Gregory T. 
Published: September 2002

ABSTRACT

CzcR is the
Rickettsia prowazekii
homolog of the
Caulobacter crescentus
global response regulator CtrA. CzcR expression partially compensates for developmental defects in
ctrA
mutant
C. crescentus
cells, and CzcR binds to all five CtrA binding sites in the
C. crescentus
replication origin. Conversely, CtrA binds to five similar sites in the putative
R. prowazekii
replication origin (
oriRp
). Also,
Escherichia coli
IHF protein binds over a central CtrA binding site in
oriRp
. Therefore, CtrA and IHF regulatory proteins have similar binding patterns in both replication origins, and we propose that CzcR is a global cell cycle regulator in
R. prowazekii
.
Analysis of the Conjugal Transfer System of the Pheromone- Independent Highly Transferable Enterococcus Plasmid pMG1: Identification of a
tra
Gene (
traA
) Up-Regulated during Conjugation
Authors: Tanimoto Koichi , Ike Yasuyoshi 
Published: September 2002

ABSTRACT

pMG1 (65.1 kbp) is a pheromone-independent
Enterococcus faecium
conjugative plasmid conferring gentamicin resistance. pMG1 is able to transfer to enterococci at a high frequency in broth mating experiments, and it does not respond to the sex pheromones which are involved in the high-frequency transfer system of some conjugative plasmids in
Enterococcus faecalis
. To analyze regulation of
tra
gene expression in pMG1, transcripts of pMG1 were examined during conjugation. RNA samples were prepared from mating mixtures 20, 40, 80, and 160 min after initiation of mating and were subsequently analyzed by Northern hybridization by using a variety of pMG1 DNA fragments as probes. One transcript of gene 71ORF2 increased to the maximal level 20 min after the start of mating. The level of this transcript decreased after 40 min of mating to the same level as the level in the control donor culture. The increase was not observed in cultures of the donor cells or recipient cells. These findings suggested that the increase was a conjugation-specific event. The 71ORF2 gene of pMG1 was disrupted by using the suicide vector pMG226 carrying an erythromycin resistance gene that is expressed in enterococci. The transfer frequencies of mutant plasmid pMG229, which had a disrupted 71ORF2 gene in pMG1, and the parent plasmid pMG1 were 1.6 × 10
−7
and 1.1 × 10
−3
per donor cell, respectively, in broth mating experiments, and the transfer frequencies of pMG229 and pMG1 were 2.7 × 10
−3
and 8.5 × 10
−2
per donor cell, respectively, in filter mating experiments. This indicated that the transfer frequency of plasmid pMG229 was reduced during broth mating and was not altered during filter mating. 71ORF2, which is designated
traA
, is a gene involved in the
tra
gene system for conjugation, and the product of this gene is associated with the formation or stabilization of mating aggregates during broth mating.
Evidence for Conformational Protection of Nitrogenase against Oxygen in
Gluconacetobacter diazotrophicus
by a Putative FeSII Protein
Authors: Ureta Alejandro , Nordlund Stefan 
Published: September 2002

ABSTRACT

The mechanisms protecting nitrogenase in
Gluconacetobacter diazotrophicus
from damage by oxygen were studied. Evidence is provided suggesting that in
G. diazotrophicus
these mechanisms include respiratory protection as well as conformational protection in which a putative FeSII Shethna protein is involved.
Novel Locus Required for Expression of High-Level Macrolide-Lincosamide-Streptogramin B Resistance in
Staphylococcus aureus
Authors: Martin P. K. , Bao Y. , Boyer E. , Winterberg K. M. , McDowell L. , Schmid M. B. , Buysse J. M. 
Published: September 2002

ABSTRACT

The
yycF1
(Ts) mutation in
Staphylococcus aureus
conferred hypersensitivity to macrolide-lincosamide-streptogramin B (MLS
B
) antibiotics on strains either containing or lacking
ermB
. The overexpression of the
S. aureus
Ssa protein restored the
yycF1
mutant to wild-type levels of susceptibility. Inactivation of
ssa
in an unmutagenized strain dramatically reduced
ermB
-based resistance. Conditional loss of function or expression of
ssa
in the
yycF1
mutant is proposed to result in the observed hypersensitivity to MLS
B
antibiotics.
Secretion of α-Amylase from
Pseudoalteromonas haloplanktis
TAB23: Two Different Pathways in Different Hosts
Authors: Tutino Maria Luisa , Parrilli Ermenegilda , Giaquinto Laura , Duilio Angela , Sannia Giovanni , Feller Georges , Marino Gennaro 
Published: September 2002

ABSTRACT

Secretion of cold-adapted α-amylase from
Pseudoalteromonas haloplanktis
TAB23 was studied in three Antarctic bacteria. We demonstrated that the enzyme is specifically secreted in the psychrophilic hosts even in the absence of a protein domain that has been previously reported to be necessary for α-amylase secretion in
Escherichia coli
. The occurrence of two different secretion pathways in different hosts is proposed.
BOTH COLOR AND GRAY SCALE SECRET IMAGES HIDING IN A COLOR IMAGE
Authors: LIN MIN-HUI , HU YU-CHEN , CHANG CHIN-CHEN 
Published: September 2002

In the past, most image hiding techniques have been applied only to gray scale images. Now, many valuable images are color images. Thus, it has become important to be able to apply image-hiding techniques to hide color images. In this paper, our proposed scheme can not only be applied to "a color host image hiding a color secret image", but also to "a color host image hiding a gray scale secret image". Our scheme utilizes the rightmost 3, 2 and 3 bits of the R, G, B channels of every pixel in the host image to hide related information from the secret image. Meanwhile, we utilize the leftmost 5, 6, 5 bits of the R, G, B channels of every pixel in the host image and set the remaining bits as zero to generate a palette. We then use the palette to conduct color quantization on the secret image to convert its 24-bit pixels into pixels with 8-bit palette index values. DES encryption is then conducted on the index values before the secret image is embedded into the rightmost 3, 2, 3 bits of the R, G, B channels of every pixel in the host image. The experimental results show that even under the worst case scenario our scheme guarantees an average host image PSNR value of 39.184 and an average PSNR value of 27.3415 for the retrieved secret image. In addition to the guarantee of the quality of host images and retrieved secret images, our scheme further strengthens the protection of the secret image by conducting color quantization and DES encryption on the secret image in advance. Therefore, our scheme not only expands the application area of image hiding, but is also practical and secure.
A HYBRID POST-PROCESSING SYSTEM FOR HANDWRITTEN CHINESE CHARACTER RECOGNITION
Authors: XU RUIFENG , YEUNG DANIEL , SHU WENHAO , LIU JIAFENG 
Published: September 2002

In this paper, a hybrid post-processing system for improving the performance of Handwritten Chinese Character Recognition is presented. In order to remove two kinds of frequently encountered errors in the recognition result, namely mis-recognized character and unrecognized character, both confusing character characteristics of the recognizer and the contextual linguistic information are utilized in our hybrid three-stage post-processing system. In the first stage, the confusing character set and a statistical Noisy-Channel model are employed to identify the most promising candidate character and append possible unrecognized similar-shaped characters into candidate character set when a candidate sequence is given. Secondly, dictionary-based approximate word matching is conducted to further append contextual linguistic-prone characters into candidate character set and bind the candidate characters into a word-lattice. Finally, a Chinese word BI-Gram Markov model is employed in the third stage to identify a most promising sentence by selecting plausible words from the word-lattice. On the average, our system achieves a 5.1% recognition rate improvement for the first candidate when the original character recognition rate is 90% for the first candidate and 95% for the top-10 candidates by an online HCCR engine.
AN EFFICIENT MULTI-VARIABLE INVERSION ALGORITHM FOR RELIABILITY EVALUATION OF COMPLEX SYSTEMS USING PATH SETS
Authors: CHATURVEDI S. K. , MISRA K. B. 
Published: September 2002

Reliability evaluation of a large and complex system is quite an involved and time-consuming process and its state-of-art is far from being called as satisfactory. This is mainly due to the fact that unionizing path sets results in large number of terms in the reliability expression. Thereafter, the process of computing numerical value of system reliability from its expression is a task not free from the build up of round-off errors. The entire process also restricts the use of a low-end PC for computing system reliability of such systems. In this paper, we propose an efficient methodology to evaluate reliability of large and complex systems based on minimal path sets; the path sets enumeration procedure used in this paper generates path sets in lexicographic and increasing order of cardinality — a condition, which is helpful in obtaining sum of disjoint products (SDP) of the system reliability expression in a compact form. Although we make use of the system connection matrix but no complicated matrix operations are performed to obtain the results. The paper further presents an improved multi-variable inversion (MVI) algorithm to evaluate system reliability in a compact form. Our approach offers an extensive reduction in the number of mutually disjoint terms and provides a minimized and compact system reliability expression. The procedure not only results in substantial saving of CPU time but also can be run on a low-end PC. To demonstrate this capability, we solve several problems of varied complexities on a low-end PC and also provide a comparison of our approach with earlier techniques available for the purpose.
FLEXOR TENOLYSIS
Authors: Feldscher Sheri B. , Schneider Lawrence H. 
Published: September 2002

Tenolysis is a well-established salvage procedure, which can be applied when non-gliding adhesions form along the surface of a tendon after injury or repair and prevent gliding of the tendon in the performance of its intended function.8,15,17,29,30,39,40,44,49Tendon adhesions will occur whenever the surface of a tendon is damaged either through the injury itself, be it laceration or crush, or by surgical manipulation.18At any point on the surface of a tendon where violation occurs, an adhesion will form in the healing period.20,26When these adhesions cannot be mobilised by an adequate course of hand therapy, tenolysis should be considered.This procedure is as difficult or more so than tendon repair itself and should not be undertaken lightly. It represents another surgical incursion into an area of previous trauma and surgery. If the procedure is not successful, the patient's hand may show no improvement or even be worse. The risk of further decreasing the circulatory supply and innervation to an already deprived finger is a real one. Rupture of the lysed tendon, a disastrous complication, is the major hazard of tenolysis.
THE BACTERIAL COLONISATION OF SILICONE OIL USED IN THE MANAGEMENT OF WOUNDS OF THE HANDS — A SOURCE OF NOSOCOMIAL INFECTION?
Authors: Thurston A. J. , McChesney A. 
Published: September 2002

For 30 years, silicone oil has been used for the management and rehabilitation of the injured hand. Its benefits accrue from its providing a non-irritant, bland, air-free medium in which the hand can undergo early movement, which prevents drying out of the tissues and helps in the separation of necrotic and infected tissue. It has been reported, however, that the silicone oil might act as a reservoir for nosocomial infection after two patients developed epidemic methicillin-resistant Staphylococcus aureus (EMRSA) infections. Since no firm guidelines exist with regard to open and/or infected wounds and the continued use of the same oil, a prospective study was set up to study the bacterial colonisation of the silicone oil. Thirty-five consecutive patients were entered into the study. The oil for each patient was changed each week but if any wound became clinically infected the oil was changed earlier. Treatment was continued until the wound was healed or until the treatment was stopped by the referring doctor. Bacteriology swabs taken from the wound and the oil before each treatment and from the oil after each treatment were analysed for bacterial colonisation. The results indicated that while bacteria were transferred into the oil from the wound, the inoculum was small and had no effect on wound healing. There was no evidence that wounds were being re-infected from the oil. The conclusion was that silicone oil remains a safe medium in which to exercise injured hands.
ENCHONDROMA IN THE HAND RETROSPECTIVE STUDY — RECURRENCE CASES
Authors: Montero Lidia Merida , Ikuta Yoshikazu , Ishida Osamu , Fujimoto Yoshinori , Nakamasu Masakazu 
Published: September 2002

This is a retrospective analysis of 21 patients with documented enchondroma of the hand. They were operated on between 1980 to 2000 with conventional curettage nd bone grafting. The objective of this study is to analyse the chance of recurrence and evaluate the effectiveness of surgical treatment. One patient had recurrence after six years. Longer follow-up period is recommended as there is a possibility of recurrence even after five years. This study revealed that enchondroma of the hand is more common on the ulnar site.
FLEXOR TENDON REPAIR, HEALING AND REHABILITATION: A BRIEF COMMENTARY
Authors: McAuliffe John A. 
Published: September 2002

Twenty years ago, we concluded that it was useless to use suture material strong enough to allow early mobilisation, since material of this sort creates problems in the form of connective tissue reaction and even tendon necrosis. It is better to use what is called "the blocked suture", which abolishes muscle tension on the repair, and, therefore, makes it possible to bring the tendon ends accurately together by fine sutures too weak to resist any muscle fore.19This statement, from Claude Verdan's Founders Lecture to the American Society for Society of the Hand only 30 years ago, highlights the dramatic rate of change in our understanding and clinical approach to flexor tendon repair. At the time these words were spoken, Verdan and some of his more adventurous contemporaries were challenging the currently accepted dictum that repair of flexor tendons divided in the digit should not be attempted. This early work on the primary repair of flexor tendons by Verdan,20Kleinert and associates,12and Kessler and Nissim,11among others, forever changed the landscape of Bunnell's "no man's land",and paved the way for the clinical advances and explosion of research into flexor tendon healing and repair that have occured in the last several decades.
FLEXOR TENDON SALVAGE AND FUNCTIONAL REDEMPTION USING THE HUNTER TENDON IMPLANT AND THE SUPERFICIALIS FINGER OPERATION
Authors: Hunter James M. , Blackmore Susan M. , Callahan Anne D. 
Published: September 2002

Although this article was published over a decade ago, the methods presented then are still timely and make a positive and reliable result possible. Superficialis finger function combined with the one-stage Hunter active tendon implant technique can produce a working hand with longevity of years. Active tendon implants have remained in place for as long as ten years to date, with continued restored function.
Elliptic problems with nonmonotone discontinuities at resonance
Authors: Nikolaos Halidias 
Published: September 2002

Using the critical point theory of Chang (1981) for locally
Lipschitz functionals, we prove an existence theorem for some
elliptic problems at resonance with no Carathéodory forcing
term.Elliptic problems with nonmonotone discontinuities at resonance (Erratum)dx.doi.org/10.1155/S108533750430905X
Guidance for Improving Life‐Cycle Design and Management of Milk Packaging
Authors: Keoleian Gregory A. , Spitzley David V. 
Published: September 2002

SummaryLife‐cycle inventory and cost‐analysis tools applied to milk packaging offer guidelines for achieving better environmental design and management of these systems. Life‐cycle solid waste, energy, and costs were analyzed for seven systems including single‐use and refillable glass bottles, single‐use and refillable high‐density polyethylene (HDPE) bottles, paperboard gable‐top cartons, linear low‐density polyethylene (LLDPE) flexible pouches, and polycarbonate refillable bottles on a basis of 1,000 gal of milk delivered. In addition, performance requirements were also investigated that highlighted potential barriers and trade‐offs for environmentally preferable alternatives. Sensitivity analyses, indicated that material production energy, postconsumer solid waste, and empty container costs were key parameters for predicting life‐cycle burdens and costs. Recent trends in recycling rates, tipping fees, and recycled materials market value had minimal effect on the results. Inventory model results for life‐cycle solid waste and energy indicated the same rank order as results from previously published life‐cycle inventory studies of container systems.Refillable HDPE and polycarbonate, and the flexible pouch were identified as the most environmentally preferable with respect to life‐cycle energy and solid waste. The greater market penetration of these containers may be limited by performance issues such as empty container storage, handling requirements, and deposit fees for refillables, and resealability and puncture resistance for the pouch.
Conoco and the Vapor Recovery Project: Using Innovation to Preserve Autonomy
Authors: Sharfman Mark , Ellington Rex T. , Meo Mark 
Published: September 2002

SummaryWe describe Conoco's closed‐loop approach to reducing undesirable emissions through vapor recovery at some of its natural gas production facilities near Corpus Christi, Texas. In response to the U.S. Clean Air Act Amendments of 1990 (CAAA), Conoco developed a technological solution that routed emissions from the facilities to fuel scrubbers and condensers to capture usable product and hazardous air pollutants. Usable product was sold. Nonsalable emissions were routed to on‐site equipment as fuel. The new technology was designed without power needs because electricity was not available. In completing these modifications, a closed system (approaching zero emissions) for these facilities was achieved. This innovation saved and earned money for the firm and allowed Conoco to retain its autonomy in these operations.The solution was so effective that the air quality permits under the CAAA were not required for these production facilities, for a total out‐of‐pocket cost of 560,000 (plus earned revenue). The firm saved 2,535,000 in initial and 1,359,000 in annual permit costs and fees. The technology recovered 210,000/yr worth of vent gas as on‐site fuel and 3,633 barrels/yr of saleable condensate valued at 58,128/ yr. At the same time, it reduced its division environmental impact by 884 tons/year of nitrogen oxides, 2,366 tons/yr of volatile organic compounds, and 495 tons/yr of other hazardous air pollutants. Payout of this 560,000 investment was less than 2 years.
The Revenge of the Machines: On Modernity, Digital Technology and Animism
Authors: Aupers Stef 
Published: September 2002

The classical assumption that scientific and technological progress are the main driving forces behind, what Weber called, the 'disenchantment of the western world', is basic knowledge in contemporary sociology. In this paper, however, it is argued that the implementation of digital technology also stimulates the religious, or more specific, animistic imagination. A qualitative analysis of
Wired
magazine (1993-2000) shows that various computer specialists, who are 'supposed' to be the pioneers of a rational, secular and disenchanted society, can be seen as 'technoanimists'. They consider our new technological surroundings as an intelligent, autonomous force and express feelings of humility. Exemplary for this phenomenon is a group of ICTexperts who refer to themselves as 'technopagans'. Paradoxically, the explanation for this unforeseen development of 're-enchantment' can be found in progress in the technological fields of Artificial Intelligence and Artificial Life. More generally, the ongoing process of rationalization seems to provide a good explanation for the contemporary emergence of technoanimism.