bluuebunny/crossref_metadata_2025 huggingface dataset:
Screen for Agents That Induce Autolysis in Bacillus subtilis
Authors: Lacriola Christopher J. , Falk Shaun P. , Weisblum Bernard
Published: October 2012

The growing prevalence of antibiotic-resistant infections underscores the need to discover new antibiotics and to use them with maximum effectiveness. In response to these needs, we describe a screening protocol for the discovery of autolysis-inducing agents that uses two
Bacillus subtilis
reporter strains, SH-536 and BAU-102. To screen chemical libraries, autolysis-inducing agents were first identified with a BAU-102-based screen and then subdivided with SH-536 into two major groups: those that induce autolysis by their direct action on the cell membrane and those that induce autolysis secondary to inhibition of cell wall synthesis. SH-536 distinguishes between the two groups of autolysis-inducing agents by synthesizing and then releasing β-galactosidase (β-Gal) in late stationary phase at a time that cells have nearly stopped growing and are therefore tolerant of cell wall synthesis inhibitors. Four hits, named compound 2, compound 3, compound 5, and compound 24, obtained previously as inducers of autolysis by screening a 10,080-compound discovery library with BAU-102, were probed with SH-536 and found to release β-Gal, indicating that their mode of action was to permeabilize the
B. subtilis
cell membrane. The four primary hits inhibited growth in
Staphylococcus aureus
,
Enterococcus faecium
,
Bacillus subtilis
, and
Bacillus anthracis
, with MICs in the 12.5- to 25-μg/ml (20 to 60 μM) range. The four primary hits were further used to probe
B. subtilis
, and their action was partially characterized with respect to the dependence of induced autolysis on specific autolysins.
Variations of Subunit ε of the Mycobacterium tuberculosis F
1
F
o
ATP Synthase and a Novel Model for Mechanism of Action of the Tuberculosis Drug TMC207
Authors: Biuković Goran , Basak Sandip , Manimekalai Malathy Sony Subramanian , Rishikesan Sankaranarayanan , Roessle Manfred , Dick Thomas , Rao Srinivasa P. S. , Hunke Cornelia , Grüber Gerhard
Published: October 2012

The subunit ε of bacterial F
1
F
O
ATP synthases plays an important regulatory role in coupling and catalysis via conformational transitions of its C-terminal domain. Here we present the first low-resolution solution structure of ε of
Mycobacterium tuberculosis
(
Mt
ε) F
1
F
O
ATP synthase and the nuclear magnetic resonance (NMR) structure of its C-terminal segment (
Mt
ε
103–120
).
Mt
ε is significantly shorter (61.6 Å) than forms of the subunit in other bacteria, reflecting a shorter C-terminal sequence, proposed to be important in coupling processes via the catalytic β subunit. The C-terminal segment displays an α-helical structure and a highly positive surface charge due to the presence of arginine residues. Using NMR spectroscopy, fluorescence spectroscopy, and mutagenesis, we demonstrate that the new tuberculosis (TB) drug candidate TMC207, proposed to bind to the proton translocating
c
-ring, also binds to
Mt
ε. A model for the interaction of TMC207 with both ε and the
c
-ring is presented, suggesting that TMC207 forms a wedge between the two rotating subunits by interacting with the residues W15 and F50 of ε and the
c
-ring, respectively. T19 and R37 of ε provide the necessary polar interactions with the drug molecule. This new model of the mechanism of TMC207 provides the basis for the design of new drugs targeting the F
1
F
O
ATP synthase in
M. tuberculosis
.
Fosfomycin-Daptomycin and Other Fosfomycin Combinations as Alternative Therapies in Experimental Foreign-Body Infection by Methicillin-Resistant Staphylococcus aureus
Authors: Garrigós C. , Murillo O. , Lora-Tamayo J. , Verdaguer R. , Tubau F. , Cabellos C. , Cabo J. , Ariza J.
Published: October 2012

The efficacy of daptomycin, imipenem, or rifampin with fosfomycin was evaluated and compared with that of daptomycin-rifampin in a tissue cage model infection caused by methicillin-resistant
Staphylococcus aureus
(MRSA). Strain HUSA 304 was used. The study yielded the following results for MICs (in μg/ml): fosfomycin, 4; daptomycin, 1; imipenem, 0.25; and rifampin, 0.03. The study yielded the following results for minimum bactericidal concentration (MBC) (in μg/ml): fosfomycin, 8; daptomycin, 4; imipenem, 32; and rifampin, 0.5. Daptomycin-rifampin was confirmed as the most effective therapy against MRSA foreign-body infections. Fosfomycin combinations with high doses of daptomycin and rifampin were efficacious alternative therapies in this setting. Fosfomycin-imipenem was relatively ineffective and did not protect against resistance.
Two Hits Are Better than One: Membrane-Active and DNA Binding-Related Double-Action Mechanism of NK-18, a Novel Antimicrobial Peptide Derived from Mammalian NK-Lysin
Authors: Yan Jiexi , Wang Kairong , Dang Wen , Chen Ru , Xie Junqiu , Zhang Bangzhi , Song Jingjing , Wang Rui
Published: October 2012

The extensive use and misuse of antibiotics in medicine result in the emergence of multidrug-resistant bacteria, creating an urgent need for the development of new chemotherapeutic agents. Nowadays, antimicrobial peptides are widely recognized as a class of promising candidates with activity against multidrug-resistant bacteria. NK-18 is a truncated peptide derived from NK-Lysin, an effector of cytotoxic T cells and natural killer cells. In this study, we studied the antibacterial mechanism of action of NK-18. The results revealed that NK-18 has potent antibacterial activity against
Escherichia coli
and
Staphylococcus aureus
. According to our findings, NK-18 is membrane active and its target of action is not only the bacterial membrane but also the DNA in the cytoplasm. The double targets of NK-18 make it difficult for bacteria to generate resistance, which may present a new strategy to defend against multidrug-resistant bacteria and provide a new lead in the design of potent antimicrobial peptides with therapeutic application in the presence of increasing resistance to conventional antibiotics.
Complete Nucleotide Sequence of the First KPC-2- and SHV-12-Encoding IncX Plasmid, pKpS90, from Klebsiella pneumoniae
Authors: Kassis-Chikhani Najiby , Frangeul Lionel , Drieux Laurence , Sengelin Christian , Jarlier Vincent , Brisse Sylvain , Arlet Guillaume , Decré Dominique
Published: October 2012

We report the complete nucleotide sequence of the pKpS90 plasmid, carrying the
bla
KPC-2
and
bla
SHV-12
genes. This plasmid was isolated from a sequence type 258 (ST258)
Klebsiella pneumoniae
strain responsible for an outbreak in a French university hospital in 2009. pKpS90 is a 53,286-bp plasmid that belongs to the IncX incompatibility group. pKpS90 consists of a backbone from IncX plasmids, in which the KPC-2-encoding Tn
4401
transposon and a
bla
SHV-12
-encoding region have been inserted.
Genome Update of Botrytis cinerea Strains B05.10 and T4
Authors: Staats Martijn , van Kan Jan A. L.
Published: October 2012

We report here an update of the
Botrytis cinerea
strains B05.10 and T4 genomes, as well as an automated preliminary gene structure annotation. High-coverage
de novo
assemblies and reference-based alignments led to a correction of wrong base calls, elimination of sequence gaps, and improved joining of contigs. The new assemblies have substantially lower numbers of scaffolds and a concomitant increase in the
N
50
.The list of protein-coding genes was generated using the evidence-driven gene predictor Augustus, with expressed sequence tag evidence and RNA-Seq data as input.
Identification of Burkholderia cenocepacia Strain H111 Virulence Factors Using Nonmammalian Infection Hosts
Authors: Schwager Stephan , Agnoli Kirsty , Köthe Manuela , Feldmann Friederike , Givskov Michael , Carlier Aurelien , Eberl Leo
Published: October 2012

Burkholderia cenocepacia
H111, a strain isolated from a cystic fibrosis patient, has been shown to effectively kill the nematode
Caenorhabditis elegans
. We used the
C. elegans
model of infection to screen a mini-Tn
5
mutant library of
B. cenocepacia
H111 for attenuated virulence. Of the approximately 5,500
B. cenocepacia
H111 random mini-Tn
5
insertion mutants that were screened, 22 showed attenuated virulence in
C. elegans
. Except for the quorum-sensing regulator
cepR
, none of the mutated genes coded for the biosynthesis of classical virulence factors such as extracellular proteases or siderophores. Instead, the mutants contained insertions in metabolic and regulatory genes. Mutants attenuated in virulence in the
C. elegans
infection model were also tested in the
Drosophila melanogaster
pricking model, and those also attenuated in this model were further tested in
Galleria mellonella
. Six of the 22 mutants were attenuated in
D. melanogaster
, and five of these were less pathogenic in the
G. mellonella
model. We show that genes encoding enzymes of the purine, pyrimidine, and shikimate biosynthesis pathways are critical for virulence in multiple host models of infection.
Genome Sequences of Three Helicobacter pylori Strains Isolated from Atrophic Gastritis and Gastric Ulcer Patients in China
Authors: You Yuanhai , Liu Lin , Zhang Maojun , Han Xifang , He Lihua , Zhu Yuanfang , Ni Peixiang , Zhang Jianzhong
Published: October 2012

Helicobacter pylori
is a bacterial pathogen which can lead to several human gastric diseases. Here we describe the genome sequences of three strains isolated from atrophic gastritis and gastric ulcers patients in China. The data will permit genomic characterization of traits that may contribute to various gastric diseases.
Whole-Genome Sequence of the Hypervirulent Clinical Strain Mycobacterium intracellulare M.i.198
Authors: Tateishi Yoshitaka , Kitada Seigo , Miki Keisuke , Maekura Ryoji , Ogura Yoshitoshi , Ozeki Yuriko , Nishiuchi Yukiko , Niki Mamiko , Hayashi Tetsuya , Hirata Kazuto , Kobayashi Kazuo , Matsumoto Sohkichi
Published: October 2012

We report herein the draft genome sequence of
Mycobacterium intracellulare
clinical strain M.i.198, which consistently exhibits hypervirulence in human patients, human macrophages
in vitro
, and immunocompetent mice.
Genome Sequence of Pseudomonas aeruginosa DQ8, an Efficient Degrader of
n
-Alkanes and Polycyclic Aromatic Hydrocarbons
Authors: Gai Zhonghui , Zhang Zhengzhi , Wang Xiaoyu , Tao Fei , Tang Hongzhi , Xu Ping
Published: October 2012

Pseudomonas aeruginosa
DQ8, which was isolated from the crude oil polluted soil in the Daqing oilfield of China, can efficiently degrade diesel, crude oil,
n
-alkanes, and polycyclic aromatic hydrocarbons (PAHs). Here, we present a 6.8-Mb assembly of its genome sequence. We have annotated 23 coding sequences (CDSs) responsible for catabolism of
n
-alkanes and PAHs.
Complete Genome Sequence of Burkholderia sp. Strain GG4, a Betaproteobacterium That Reduces 3-Oxo-
N
-Acylhomoserine Lactones and Produces Different
N
-Acylhomoserine Lactones
Authors: Hong Kar-Wai , Koh Chong-Lek , Sam Choon-Kook , Yin Wai-Fong , Chan Kok-Gan
Published: October 2012

Burkholderia
sp. strain GG4, isolated from the ginger rhizosphere, possesses a unique
N
-acylhomoserine lactone (AHL)-modifying activity that reduces 3-oxo-AHLs to 3-hydroxy-AHLs. To the best of our knowledge, this is the first sequenced genome from a bacterium of the genus
Burkholderia
that shows both quorum-sensing and signaling confusion activities.
Genome Sequence of Pseudomonas mendocina DLHK, Isolated from a Biotrickling Reactor
Authors: Wong Chi Fat , Niu Hejingying , Jiang Jingwei , Li Jun , Chan Charis May Ngor , Leung Dennis Yiu Cheong , Leung Frederick Chi Ching
Published: October 2012

Pseudomonas mendocina
DLHK is an aerobic bacterium isolated from a biotrickling reactor which can remove nitric oxide, a common air pollutant from combustion exhaust gas. Here, we present the draft genome of
Pseudomonas mendocina
DLHK.
Draft Genome Sequence of Rhodovulum sp. Strain PH10, a Phototrophic Alphaproteobacterium Isolated from a Soil Sample of Mangrove of Namkhana, India
Authors: Khatri Indu , Nupur  , Korpole Suresh , Subramanian Srikrishna , Pinnaka Anil Kumar
Published: October 2012

We report the 4.8-Mb draft genome of
Rhodovulum
sp. strain PH10, a phototrophic bacterium belonging to class
Alphaproteobacteria
, isolated from a soil sample collected from the mangrove forest of Namkhana in India. This genome is the first from the genus
Rhodovulum
and will lead to a better understanding of the genes/pathways involved in activities like phototrophic growth and nitrogen fixation in this group of bacteria.
Enhanced Butanol Production Obtained by Reinforcing the Direct Butanol-Forming Route in Clostridium acetobutylicum
Authors: Jang Yu-Sin , Lee Jin Young , Lee Joungmin , Park Jin Hwan , Im Jung Ae , Eom Moon-Ho , Lee Julia , Lee Sang-Hyun , Song Hyohak , Cho Jung-Hee , Seung Do Young , Lee Sang Yup
Published: October 2012

Butanol is an important industrial solvent and advanced biofuel that can be produced by biphasic fermentation by
Clostridium acetobutylicum
. It has been known that acetate and butyrate first formed during the acidogenic phase are reassimilated to form acetone-butanol-ethanol (cold channel). Butanol can also be formed directly from acetyl-coenzyme A (CoA) through butyryl-CoA (hot channel). However, little is known about the relative contributions of the two butanol-forming pathways. Here we report that the direct butanol-forming pathway is a better channel to optimize for butanol production through metabolic flux and mass balance analyses. Butanol production through the hot channel was maximized by simultaneous disruption of the
pta
and
buk
genes, encoding phosphotransacetylase and butyrate kinase, while the

adhE1
D485G

gene, encoding a mutated aldehyde/alcohol dehydrogenase, was overexpressed. The ratio of butanol produced through the hot channel to that produced through the cold channel increased from 2.0 in the wild type to 18.8 in the engineered BEKW(pPthlAAD
**
) strain. By reinforcing the direct butanol-forming flux in
C. acetobutylicum
, 18.9 g/liter of butanol was produced, with a yield of 0.71 mol butanol/mol glucose by batch fermentation, levels which are 160% and 245% higher than those obtained with the wild type. By fed-batch culture of this engineered strain with
in situ
recovery, 585.3 g of butanol was produced from 1,861.9 g of glucose, with the yield of 0.76 mol butanol/mol glucose and productivity of 1.32 g/liter/h. Studies of two butanol-forming routes and their effects on butanol production in
C. acetobutylicum
described here will serve as a basis for further metabolic engineering of clostridia aimed toward developing a superior butanol producer.

IMPORTANCE
Renewable biofuel is one of the answers to solving the energy crisis and climate change problems. Butanol produced naturally by clostridia has superior liquid fuel characteristics and thus has the potential to replace gasoline. Due to the lack of efficient genetic manipulation tools, however, strain improvement has been rather slow. Furthermore, complex metabolic characteristics of acidogenesis followed by solventogenesis in this strain have hampered development of engineered clostridia having highly efficient and selective butanol production capability. Here we report for the first time the results of systems metabolic engineering studies of two butanol-forming routes and their relative importances in butanol production. Based on these findings, a metabolically engineered
Clostridium acetobutylicum
strain capable of producing butanol to a high titer with high yield and selectivity could be developed by reinforcing the direct butanol-forming flux.
Solitary metachronous splenic metastasis from cutaneous melanoma
Authors: Gavriilidis Paschalis , Goupou Eleni
Published: October 2012

Melanoma has been found to metastasise to the spleen, usually in cases of disseminated disease. Solitary splenic metastasis from cutaneous melanoma is very rare. Herein we report the case of a 43-year-old man who developed solitary splenic metastasis from cutaneous melanoma. The patient was operated for T4bN1aMo superficial spreading melanoma of the anterior thoracic wall. He subsequently underwent left axillary lymph node dissection due to a positive sentinel lymph node. The 33 retrieved lymph nodes were negative for metastasis. The patient received adjuvant therapy with high-dose interferon α-2b. After 27 months and during the follow-up visit an increasing lactate dehydrogenase serum level was observed. Furthermore, CT of the whole body revealed a solitary hypodense tumour of the spleen 9 cm×6 cm. Curative splenectomy was performed and the histopathological report confirmed metastatic melanoma to the spleen.
Significance of deep T-wave inversions in asymptomatic athletes with normal cardiovascular examinations: practical solutions for managing the diagnostic conundrum
Authors: Wilson M G , Sharma S , Carré F , Charron P , Richard P , O'Hanlon R , Prasad S K , Heidbuchel H , Brugada J , Salah O , Sheppard M , George K P , Whyte G , Hamilton B , Chalabi H
Published: October 2012

Preparticipation screening programmes for underlying cardiac pathologies are now commonplace for many international sporting organisations. However, providing medical clearance for an asymptomatic athlete without a family history of sudden cardiac death (SCD) is especially challenging when the athlete demonstrates particularly abnormal repolarisation patterns, highly suggestive of an inherited cardiomyopathy or channelopathy. Deep T-wave inversions of ≥2 contiguous anterior or lateral leads (but not aVR, and III) are of major concern for sports cardiologists who advise referring team physicians, as these ECG alterations are a recognised manifestation of hypertrophic cardiomyopathy (HCM) and arrhythmogenic right ventricular cardiomyopathy (ARVC). Subsequently, inverted T-waves may represent the first and only sign of an inherited heart muscle disease, in the absence of any other features and before structural changes in the heart can be detected. However, to date, there remains little evidence that deep T-wave inversions are always pathognomonic of either a cardiomyopathy or an ion channel disorder in an asymptomatic athlete following long-term follow-up.

This paper aims to provide a systematic review of the prevalence of T-wave inversion in athletes and examine T-wave inversion and its relationship to structural heart disease, notably HCM and ARVC with a view to identify young athletes at risk of SCD during sport. Finally, the review proposes clinical management pathways (including genetic testing) for asymptomatic athletes demonstrating significant T-wave inversion with structurally normal hearts.
Do big athletes have big hearts? Impact of extreme anthropometry upon cardiac hypertrophy in professional male athletes
Authors: Riding Nathan R , Salah Othman , Sharma Sanjay , Carré François , O'Hanlon Rory , George Keith P , Hamilton Bruce , Chalabi Hakim , Whyte Gregory P , Wilson Mathew G
Published: October 2012

Aim

Differentiating physiological cardiac hypertrophy from pathology is challenging when the athlete presents with extreme anthropometry. While upper normal limits exist for maximal left ventricular (LV) wall thickness (14 mm) and LV internal diameter in diastole (LVIDd, 65 mm), it is unknown if these limits are applicable to athletes with a body surface area (BSA) >2.3 m2.

Purpose

To investigate cardiac structure in professional male athletes with a BSA>2.3 m2, and to assess the validity of established upper normal limits for physiological cardiac hypertrophy.

Methods

836 asymptomatic athletes without a family history of sudden death underwent ECG and echocardiographic screening. Athletes were grouped according to BSA (Group 1, BSA>2.3 m2, n=100; Group 2, 2–2.29 m2, n=244; Group 3, <1.99 m2, n=492).

Results

There was strong linear relationship between BSA and LV dimensions; yet no athlete with a normal ECG presented a maximal wall thickness and LVIDd greater than 13 and 65 mm, respectively. In Group 3 athletes, Black African ethnicity was associated with larger cardiac dimensions than either Caucasian or West Asian ethnicity. Three athletes were diagnosed with a cardiomyopathy (0.4% prevalence); with two athletes presenting a maximal wall thickness >13 mm, but in combination with an abnormal ECG suspicious of an inherited cardiac disease.

Conclusion

Regardless of extreme anthropometry, established upper limits for physiological cardiac hypertrophy of 14 mm for maximal wall thickness and 65 mm for LVIDd are clinically appropriate for all athletes. However, the abnormal ECG is key to diagnosis and guides follow-up, particularly when cardiac dimensions are within accepted limits.
The provision of diagnosis at emergency department discharge: a pilot study
Authors: Wen Leana S , Kosowsky Joshua M , Gurrola Edith R , Camargo Carlos A
Published: October 2012

Objectives

Understanding the cause of patients’ symptoms usually involves identification of a pathological diagnosis. Anecdotal reports suggest that emergency department (ED) providers do not prioritise giving pathological diagnoses, and often reiterate the patient's symptom as the discharge ‘diagnosis’. Our pilot study sought to identify the proportion of patients at a large teaching hospital who receive a symptomatic versus pathological diagnosis at ED discharge.

Methods

We performed a chart review of all adult patients who were discharged from an urban ED in the USA, with an 88 000 annual visit volume. All charts of patients presenting with the three most common ED chief complaints (chest pain, abdominal pain and headache) were reviewed by two reviewers. Charts were coded as either symptomatic or pathological diagnosis based on the discharge diagnosis provided by the attending physician. Those with discrepant coding by the two reviewers were subject to review by a third adjudicator.

Results

797 charts met the inclusion criteria. Five charts (0.6%) were coded differently by the two reviewers; a discussion with the third reviewer resulted in consensus in all cases. For patients presenting with chest pain, abdominal pain and headache, the proportion that received a pathological ED discharge diagnosis were 17%, 43% and 41%, respectively.

Conclusions

According to our pilot study, most patients are discharged from the ED without a pathological diagnosis that explains the likely cause of their symptoms. Future studies will investigate whether this finding is consistent across institutions, and whether provision of a pathological diagnosis affects clinical outcomes and patient satisfaction.
Endovascular treatment of ruptured dissecting aneurysms of the posterior inferior cerebellar artery
Authors: Ishihara Hideaki , Tateshima Satoshi , Jahan Reza , Gonzalez Nestor , Duckwiler Gary , Vinuela Fernando
Published: October 2012

Background

Dissecting aneurysms of the posterior inferior cerebellar artery (PICA) are rare, with optimal treatment strategies not well established according to the location of the aneurysm on the PICA. We present our single-center experience of endovascular treatment of ruptured dissecting aneurysms of the PICA.

Methods

Nine patients with ruptured dissecting aneurysms of the PICA were treated with endovascular embolization at our facility from August 1997 to December 2011. A retrospective chart review study was conducted to examine the efficacy of endovascular treatment and clinical outcome.

Results

The shape of the aneurysms was saccular in five cases, fusiform in three cases and an abrupt cut-off of the PICA in one case. Aneurysmal sac embolization was feasible in five cases and parent artery (PICA) occlusion was performed in four cases. Eight cases (89%) achieved good recovery (modified Rankin Score ≤2). There were no clinical/technical complications in this small series.

Conclusions

Endovascular treatment of ruptured dissecting aneurysms of the PICA is safe and efficient.
Long‐term outcome of Cavalier King Charles spaniel dogs with clinical signs associated with Chiari‐like malformation and syringomyelia
Authors: Plessas I. N. , Rusbridge C. , Driver C. J. , Chandler K. E. , Craig A. , McGonnell I. M. , Brodbelt D. C. , Volk H. A.
Published: October 2012

The disease complex Chiari‐like malformation (CM) and syringomyelia (SM) has been associated with the development of neuropathic pain (NeP), and commonly affects Cavalier King Charles spaniels (CKCS). This prospective cohort study followed 48 CKCSs with CM and/or SM and clinical signs suggestive of NeP for a period of 39 (± 14.3) months from diagnosis. At the end of the study, 36 dogs were still alive; five dogs died of an unrelated or unknown cause, and seven were euthanased due to severe clinical signs suggestive of NeP. During the follow‐up period, the clinical signs of scratching, facial rubbing behaviour, vocalisation and exercise ability were evaluated. Nine out of 48 dogs stopped scratching (P< 0.001), but there was no statistically significant change in the number of dogs exhibiting exercise intolerance, vocalisation or facial rubbing behaviour. The overall severity of clinical signs based on a visual analogue scale (VAS) (0 mm: no clinical signs 100 mm: severe clinical signs) increased (from median 75 mm (interquartile ranges (IQR) 68–84) to 84 mm (IQR 71.5–91), P< 0.001). A quarter of the dogs were static or improved. In general, the majority of the owners felt that the quality of life of their dogs was acceptable. Medical treatments received were gabapentin or pregabalin and/or intermittently, carprofen. The owner's perception of their animal's progress, and progress based on VAS, had strong positive correlation (Spearman's rank correlation (sr) 0.74, P< 0.001). Overall, this study suggests that clinical signs suggestive of NeP progress in three‐quarters of CKCSs with CM and/or SM.
Exercise training prevents the development of cardiac dysfunction in the low-dose streptozotocin diabetic rats fed a high-fat diet
Authors: Epp Riley A. , Susser Shanel E. , Morissette Marc P. , Kehler D. Scott , Jassal Davinder S. , Duhamel Todd A.
Published: October 2012

This study tested the hypothesis that exercise training would prevent the development of diabetes-induced cardiac dysfunction and altered expression of sarcoplasmic reticulum Ca2 +-transport proteins in the low-dose streptozotocin-induced diabetic rats fed a high-fat diet (HFD+STZ). Male Sprague–Dawley rats (4 weeks old; 125–150 g) were made diabetic using a high-fat diet (40% fat, w/w) and a low-dose of streptozotocin (35 mg·(kg body mass)–1) by intravenous injection. Diabetic animals were divided among a sedentary group (Sed+HFD+STZ) or an exercise-trained group (Ex+HFD+STZ) that accumulated 3554 ± 338 m·day–1of voluntary wheel running (mean ± SE). Sedentary animals fed a low-fat diet served as the control (Sed+LFD). Oral glucose tolerance was impaired in the sedentary diabetic group (1179 ± 29; area under the curve (a.u.c.)) compared with that in the sedentary control animals (1447 ± 42 a.u.c.). Although left ventricular systolic function was unchanged by diabetes, impaired E/A ratios (i.e., diastolic function) and rates of pressure decay (–dP/dt) indicated the presence of diastolic dysfunction. Diabetes also reduced SERCA2a protein content and maximal SERCA2a activity (Vmax) by 21% and 32%, respectively. In contrast, the change in each parameter was attenuated by exercise training. Based on these data, it appears that exercise training prevented the development of diabetic cardiomyopathy and the dysregulation of sarcoplasmic reticulum protein content in an inducible animal model of type 2 diabetes.
HEURISTIC AND EXACT SOLUTION METHOD FOR CONVEX NONLINEAR KNAPSACK PROBLEM
Authors: ZHANG BIN , CHEN BO
Published: October 2012

In this paper, we consider a class of convex nonlinear knapsack problems in which all decision variables are integer and the objective and knapsack functions are nonlinear. This generalized problem is characterized by positive marginal cost (PMC) and increasing marginal loss-cost ratio (IMLCR). By analyzing the structural properties of the problem, we develop an efficient heuristic and propose search and branching rules to improve the branch and bound method for solving exact solution. Numerical study is done for showing the effectiveness of the proposed heuristic and the modified branch and bound method.
QUANTUM DISCORD UNDER SYSTEM–ENVIRONMENT COUPLING: THE TWO-QUBIT CASE
Authors: XU JIN-SHI , LI CHUAN-FENG
Published: October 2012

Open quantum systems have attracted great attention, since inevitable coupling between quantum systems and their environment greatly affects the features of interest of these systems. Quantum discord, is a measure of the total nonclassical correlation in a quantum system that includes, but is not exclusive to, the distinct property of quantum entanglement. Quantum discord can exist in separated quantum states and plays an important role in many fundamental physics problems and practical quantum information tasks. There have been numerous investigations on quantum discord and its counterpart classical correlation. This short review focuses on highlighting the system–environment dynamics of two-qubit quantum discord and the influence of initial system–environment correlations on the dynamics of open quantum systems. The external control effect on the dynamics of open quantum systems are involved. Several related experimental works are discussed.
PROPERTIES OF Z = 120 NUCLEI AND THE α-DECAY CHAINS OF THE 292, 304120 ISOTOPES USING RELATIVISTIC AND NONRELATIVISTIC FORMALISMS
Authors: AHMAD SHAKEB , BHUYAN M. , PATRA S. K.
Published: October 2012

The ground state and first intrinsic excited state of superheavy nuclei with Z = 120 and N = 160–204 are investigated using both nonrelativistic Skyrme–Hartree–Fock (SHF) and the axially deformed relativistic mean field (RMF) formalisms. We employ a simple BCS pairing approach for calculating the energy contribution from pairing interaction. The results for isotopic chain of binding energy (BE), quadrupole deformation parameter, two neutron separation energies and some other observables are compared with the finite range droplet model (FRDM) and some recent macroscopic–microscopic calculations. We predict superdeformed ground state solutions for almost all the isotopes. Considering the possibility of magic neutron number, two different modes of α-decay chains 292120 and 304120 are also studied within these frameworks. The Qα-values and the half-life [Formula: see text] for these two different modes of decay chains are compared with FRDM and recent macroscopic–microscopic calculations. The calculation is extended for the α-decay chains of 292120 and 304120 from their excited state configuration to respective configuration, which predicts long half-life [Formula: see text] (in seconds).
DEVELOPING LBM-BASED FLUX SOLVER AND ITS APPLICATIONS IN MULTI-DIMENSION SIMULATIONS
Authors: QU KUN , SHU CHANG , CAI JINSHENG
Published: October 2012

In this paper, a new flux solver was developed based on a lattice Boltzmann model. Different from solving discrete velocity Boltzmann equation and lattice Boltzmann equation, Euler/Navier-Stokes (NS) equations were solved in this approach, and the flux at the interface was evaluated with a compressible lattice Boltzmann model. This method combined lattice Boltzmann method with finite volume method to solve Euler/NS equations. The proposed approach was validated by some simulations of one-dimensional and multi-dimensional problems.
SIMULATION OF VORTEX STRUCTURE IN SUPERSONIC FREE SHEAR LAYER USING PSE METHOD
Authors: GUO XIN , WANG QIANG
Published: October 2012

The method of parabolized stability equations (PSE) are applied in the analysis of nonlinear stability and the simulation of flow structure in supersonic free shear layer. High accuracy numerical techniques including self-similar basic flow, high order differential method, appropriate transformation and decomposition of nonlinear terms are adopted and developed to solve the PSE effectively for free shear layer. The spatial evolving unstable waves which dominate the flow structure are investigated through nonlinear coupling spatial marching methods. The nonlinear interactions between harmonic waves are further analyzed and instantaneous flow field are obtained by adding the harmonic waves into basic flow. Relevant data agree well with that of DNS. The results demonstrate that T-S wave does not keeping growing exponential as the linear evolution, the energy transfer to high order harmonic modes and finally all harmonic modes get saturation due to the nonlinear interaction; Mean flow distortion is produced by the nonlinear interaction between the harmonic and its conjugate harmonic, makes great change to the average flow and increases the thickness of shear layer; PSE methods can well capture the large scale nonlinear flow structure in the supersonic free shear layer such as vortex roll-up, vortex pairing and nonlinear saturation.
EXPERIMENTAL INVESTIGATIONS OF ADSORBED NATURAL GAS STORAGE SYSTEM WITH ENHANCED THERMAL MANAGEMENT
Authors: RAHMAN KAZI AFZALUR , LOH WAI SOONG , NG KIM CHOON , CHUN WONGEE
Published: October 2012

An adsorbed natural gas (ANG) storage system with internal thermal control, based on fin and tube type heat exchanger is investigated in this study. The adsorbent bed, which consists of Maxsorb III activated carbon packed in between copper fins and tubes, is demonstrated to study the storage capacity and thermal management of the ANG storage system. The cylinder is pressurized up to 35 bar and water is circulated through the tubes during charge process for quick removal of adsorption heat, thus to increase the storage capacity. Similarly, the adsorbent bed is heated up during discharge process to maximize the gas delivery. The current experimental arrangement presented shows higher storage capacity and better thermal management than the adsorbent bed without fin and tube arrangement.
PERFORMANCE OF A MICRO ATOMIZER UNDER SINGLE-FLUID AND TWIN-FLUID MICRO-ENCAPSULATION PROCESS
Authors: LIN TIEN-CHU
Published: October 2012

This research investigates the performance of an assembly micro-atomizer under single-fluid and twin-fluid operational conditions of micro-encapsulation process. Alginate and CaCl2 aqueous solution are used as the membrane material and hardening agent, respectively. The high speed images were taken to investigate the formation processes of the microcapsules. Results showed that the formation of the microcapsules depends on the instability modes of the liquid column including asymmetry mode, helical mode, sinusoidal mode and spray developing mode as Reynolds number was increased from 221 to 2210. Excitation at resonance frequency of 2.18 kHz of this system resulted in the production of uniform-sized microcapsules. Moreover, SMD equal to 20 μm can be achieved in low GLR under twin-fluid atomization process. It is not easy to achieve by commercial apparatus.
INVESTIGATION ON FORMATION AND HARDENING PROCESS OF MICROCAPSULES UNDER EXCITATION
Authors: LIN TIEN-CHU
Published: October 2012

This research investigates the micro-encapsulation process with a pressure-type micro-atomizer. Alginate and CaCl 2 aqueous solution are used as the membrane material and hardening agent, respectively. The high speed images were taken to investigate the formation processes of the microcapsules. Results show that the geometric shape of the microcapsules was sensitive to the droplet flying distant and the concentration of alginate aqueous, however, insensitive to the concentration of CaCl 2 aqueous. Results also show that the membrane thickness of the microcapsules was controlled by the diffusion processes of calcium chloride. An empirical formula was derived to describe the rate change of the membrane thickness in the hardening processes.
AERODYNAMIC ANALYSIS OF A ROLLING WRAPAROUND FIN PROJECTILE IN SUPERSONIC FLOW
Authors: KIM JUNG-YOUNG , CHO SUNG-IN , LEE IN , NA HYOUNG-JIN , JUNG SANG-YOUNG
Published: October 2012

In this paper, the roll characteristics of a rolling wraparound fin projectile have been investigated in supersonic region. Computation of the flowfield was performed using a time-marching, three-dimensional Euler equation in a body fixed rotating coordinate frame. First, the roll producing moment coefficients of a projectile were obtained from the flowfiled solution at various Mach numbers and compared with the experimental and numerical results. They showed favorable agreement with experimental results in magnitude and sign. Next, the roll damping moment coefficients of a rolling wraparound fin were computed and compared with correlation based on experiment data. The correlation gave a somewhat larger value in magnitude than the present computation. However, the computed values agreed well with correlation in the trend.
ELECTROSTATIC EFFECTS IN PNEUMATIC TRANSPORT OF GRANULAR MATERIALS
Authors: LIM ELDIN WEE CHUAN , YAO JUN , ZHAO YANLIN
Published: October 2012

The methodology of coupling the Discrete Element Method (DEM) with Computational Fluid Dynamics (CFD) was applied for computational studies of pneumatic transport of granular materials through vertical and horizontal pipes in the presence of electrostatic effects. The simulations showed that a thin layer of particles formed and remained adhered to the pipe walls during the pneumatic conveying process due to the effects of strong electrostatic forces of attraction towards the pipe walls. Particle concentrations were generally higher near the pipe walls than at the pipe centre resulting in the ring flow pattern observed in previous experimental studies. The close correspondence between particle velocity vectors and fluid drag force vectors was indicative of the importance of fluid drag forces in influencing particle behaviors. In contrast, the much weaker particle-particle electrostatic repulsion forces had negligible effects on particle behaviors within the system under all operating conditions considered. The electrostatic field strength developed during pneumatic conveying increased with decreasing flow rate due to increased amount of particle-wall collisions. Based on dynamic analyses of forces acting on individual particles, it may be concluded that electrostatic effects played a dominant role in influencing particle behaviors during pneumatic conveying at low flow rates while drag forces became more important at high flow rates.
TURBULENCE IN THICK LAYERS
Authors: SHATS MICHAEL , XIA HUA , BYRNE DAVID
Published: October 2012

Properties of turbulence, such as the direction of the energy cascade depend on the flow dimensionality. Recent experimental results reveal new physics understanding of flows in thick layers. We show that the flow dimensionality can be characterized by the flow damping and that a comparison of the decay rate with that of a quasi-2D flow can be used as a measure of dimensionality of a turbulent flow in a layer. This dimensionality, however can be strongly affected if large scale coherent vortices are present in the flow. These vortices can imposed twodimensionality and reduce the damping rate. Finally we show that even in thick layers with unperturbed free surface, turbulent flow can be viewed as co-existing 2D top sub-layer and the bulk 3D flow.
PREDICTION OF "S" CHARACTERISTICS OF A PUMP-TURBINE WITH SMALL OPENING BASED ON V2F MODEL
Authors: LIU JINTAO , LIU SHUHONG , WU YULIN , SUN YUEKUN , ZUO ZHIGANG
Published: October 2012

The characteristic of a pump-turbine during the whole starting or stopping period couldn't be calculated accurately by CFD method and most of turbulence models were found inaccurate in the calculation of small opening condition, so a proper turbulence model was needed for the further study of pump-turbine. V2F model which was valid to the solid wall and SST k-ω model were used to calculate the pump-turbine with two openings that one was a small opening and the other was large opening. Results showed that V2F model can be used to simulate characteristics of pump-turbine in the whole opening range and the SST k-ω model can be used only for large openings. Results of V2F model are accuracy and it realizes the real flow in the near wall region. Results of V2F model can obtain small vortexes and some complex flow phenomenon and they are much different from results of SST k-ω model. The V2F model might be used to simulate the starting or stopping period of a pump-turbine.
Excavation-parallel laser scanning of a medieval cesspit in the archaeological zone cologne, germany
Authors: Schreiber Stephan , Hinzen Klaus G. , Fleischer Claus , Schütte Sven
Published: October 2012

During the construction of an underground museum in the historic city center of Cologne, Germany, large parts of the Roman and medieval city are being excavated. The newly excavated remains as well as remains of the Roman city, which had already been excavated in 1954, exhibit structural damages. While at first deficiencies in the construction were assumed to be the cause of the damages, in 2003 a seismogenic origin was suggested. To further test this hypothesis of seismically induced slope movements and other possible causes, a multidisciplinary project was started. One step in this project is the documentation of the damages using a 3D laser scanner, followed by a quantitative damage analysis. This article presents the 3D documentation and the quantitative damage analysis of a recently excavated medieval cesspit. The 8.3m-deep cesspit was mapped during 11 campaigns using a phase-based 3D laser scanner. Due to the static conditions of the cesspit, the structure could not be excavated in its entirety. After the excavation of every 1-2m-section, restoration work had to be done to avoid a collapse of the construction. The laser scanning technique offered the possibility of working parallel to the excavation so the original conditions of each section could be documented before the restoration. The resulting models were used to identify, classify, and quantify the structural damages of the cesspit.
New opportunities for New SQL
Authors: Stonebraker Michael
Published: October 2012

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Michael Stonebraker expects a substantial increase in the number of New SQL engines using a variety of architectures in the near future.
Keeping technology promises
Authors: DeMillo Richard A.
Published: October 2012

Considering new models for educational technology and methods.
Task contingencies and perceptual strategies shape behavioral effects on neuronal response profiles
Authors: Sato Nobuya , Page William K. , Duffy Charles J.
Published: October 2012

We presented optic flow simulating eight directions of self-movement in the ground plane, while monkeys performed delayed match-to-sample tasks, and we recorded dorsal medial superior temporal (MSTd) neuronal activity. Randomly selected sample headings yield smaller test responses to the neuron's preferred heading when it is near the sample's heading direction and larger test responses to the preferred heading when it is far from the sample's heading. Limiting test stimuli to matching or opposite headings suppresses responses to preferred stimuli in both test conditions, whereas focusing on each neuron's preferred vs. antipreferred stimuli enhances responses to the antipreferred stimulus. Match vs. opposite paradigms create bimodal heading profiles shaped by interactions with late delay-period activity. We conclude that task contingencies, determining the prior probabilities of specific stimuli, interact with the monkeys' perceptual strategy for optic flow analysis. These influences shape attentional and working memory effects on the heading direction selectivities and preferences of MSTd neurons.
Ca2+-activated ion currents triggered by ryanodine receptor-mediated Ca2+release control firing of inhibitory neurons in the prepositus hypoglossi nucleus
Authors: Saito Yasuhiko , Yanagawa Yuchio
Published: October 2012

Spontaneous miniature outward currents (SMOCs) are known to exist in smooth muscles and peripheral neurons, and evidence for the presence of SMOCs in central neurons has been accumulating. SMOCs in central neurons are induced through Ca2+-activated K+(KCa) channels, which are activated through Ca2+-induced Ca2+release from the endoplasmic reticulum via ryanodine receptors (RyRs). Previously, we found that some neurons in the prepositus hypoglossi nucleus (PHN) showed spontaneous outward currents (SOCs). In the present study, we used whole cell recordings in slice preparations of the rat brain stem to investigate the following: 1) the ionic mechanisms of SOCs, 2) the types of neurons exhibiting frequent SOCs, and 3) the effect of Ca2+-activated conductance on neuronal firing. Pharmacological analyses revealed that SOCs were induced via the activation of small-conductance-type KCa(SK) channels and RyRs, indicating that SOCs correspond to SMOCs. An analysis of the voltage responses to current pulses of the fluorescence-expressing inhibitory neurons of transgenic rats revealed that inhibitory neurons frequently exhibited SOCs. Abolition of SOCs via blockade of SK channels enhanced the frequency of spontaneous firing of inhibitory PHN neurons. However, abolition of SOCs via blockade of RyRs reduced the firing frequency and hyperpolarized the membrane potential. Similar reductions in firing frequency and hyperpolarization were also observed when Ca2+-activated nonselective cation (CAN) channels were blocked. These results suggest that, in inhibitory neurons in the PHN, Ca2+release via RyRs activates SK and CAN channels, and these channels regulate spontaneous firing in a complementary manner.
Clinical Manifestations of Aortocaval Fistulas in Ruptured Abdominal Aortic Aneurysm: Report of Two Cases
Authors: Psathas Emmanouil D. , Lioudaki Stella , Doulaptsis Mikes , Charalampoudis Petros , Klonaris Chris , Verikokos Chris
Published: October 2012

Aortocaval fistula (ACF) is an unusual complication of ruptured abdominal aortic aneurysm (AAA), involving less than 3–6% of all ruptured cases. The clinical presentation is often obscure, depending on the coexistence of retroperitoneal rupture and hemodynamic instability. Prompt preoperative diagnosis is essential in order to plan the operative approach and improve patient’s outcome. We report the surgical treatment of two patients presented in the emergency department with ACF due to ruptured AAA, each with different clinical presentation, emphasizing the high index of suspicion needed by the clinician to early diagnose and treat this often lethal condition. Operative strategy and special considerations in the management of this subgroup of patients are also discussed.
Nonmetastatic Ewing’s Sarcoma of the Lumbar Spine in an Adult Patient
Authors: Iacoangeli Maurizio , Dobran Mauro , Di Rienzo Alessandro , di Somma Lucia Giovanna Maria , Alvaro Lorenzo , Moriconi Elisa , Nocchi Niccolò , Gladi Maurizio , Scerrati Massimo
Published: October 2012

Although the spine is frequently involved in metastatic Ewing's sarcoma, primary involvement of the spine, beside sacrum, is much less frequent, especially in adult patients. Because of the low incidence of these tumors, there are currently no clinical guidelines outlining their management and a multitude of therapeutic strategies have been employed with varying success. The definitive management of Ewing's sarcoma of the spine, as in other locations, could include the combination of three main modalities: aggressive surgery, radiotherapy, and combined chemotherapy. Whenever possible, en bloc spondylectomy or extralesional resection is preferable, providing a better oncological result with a longer survival and a better preservation of the spine biomechanics. This is the lesson we learned about the case, we present here, of nonmetastatic lumbar localization by Ewing’s sarcoma in as adult patient.