bluuebunny/crossref_metadata_2025 huggingface dataset:
A robust geometry estimation method for spiral, sequential and circular cone‐beam micro‐CT
Authors: Sawall Stefan , Knaup Michael , Kachelrieß Marc
Published: August 2012

Purpose:

The authors propose a novel method for misalignment estimation of micro‐CT scanners using an adaptive genetic algorithm.

Methods:

The proposed algorithm is able to estimate the rotational geometry, the direction vector of table movement and the displacement between different imaging threads of a dual source or even multisource scanner. The calibration procedure does not rely on dedicated calibration phantoms and a sequence scan of a single metal bead is sufficient to geometrically calibrate the whole imaging system for spiral, sequential, and circular scan protocols. Dual source spiral and sequential scan protocols in micro‐computed tomography result in projection data that—besides the source and detector positions and orientations—also require a precise knowledge of the table direction vector to be reconstructed properly. If those geometric parameters are not known accurately severe artifacts and a loss in spatial resolution appear in the reconstructed images as long as no geometry calibration is performed. The table direction vector is further required to ensure that consecutive volumes of a sequence scan can be stitched together and to allow the reconstruction of spiral data at all.

Results:

The algorithm's performance is evaluated using simulations of a micro‐CT system with known geometry and misalignment. To assess the quality of the algorithm in a real world scenario the calibration of a micro‐CT scanner is performed and several reconstructions with and without geometry estimation are presented.

Conclusions:

The results indicate that the algorithm successfully estimates all geometry parameters, misalignment artifacts in the reconstructed volumes vanish, and the spatial resolution is increased as can be shown by the evaluation of modulation transfer function measurements.
Sequential Inter- and Intrasubunit Rearrangements During Activation of Dimeric Metabotropic Glutamate Receptor 1
Authors: Hlavackova Veronika , Zabel Ulrike , Frankova Daniela , Bätz Julia , Hoffmann Carsten , Prezeau Laurent , Pin Jean-Philippe , Blahos Jaroslav , Lohse Martin J.
Published: August 2012

Both subunits in the metabotropic glutamate receptor 1 dimer move relative to each other before one adopts an active conformation.
A Paravascular Pathway Facilitates CSF Flow Through the Brain Parenchyma and the Clearance of Interstitial Solutes, Including Amyloid β
Authors: Iliff Jeffrey J. , Wang Minghuan , Liao Yonghong , Plogg Benjamin A. , Peng Weiguo , Gundersen Georg A. , Benveniste Helene , Vates G. Edward , Deane Rashid , Goldman Steven A. , Nagelhus Erlend A. , Nedergaard Maiken
Published: August 2012

Cerebrospinal fluid flows through channels around brain blood vessels that are bounded by astrocytic endfeet, mediated by water transport through aquaporin-4.
Sensing Sun Damage
Authors: Anandasabapathy Niroshana
Published: August 2012

Small RNAs may spur skin cell responses to sun damage.
No More Gasping for Air with GSPE
Authors: Reznik Marina
Published: August 2012

Grape seed extract suppresses inflammation and airway hyperresponsiveness in a murine model of asthma.
Streptococcus pneumoniae Transposon Tn
1545
/Tn
6003
Changes to Tn
6002
Due to Spontaneous Excision in Circular Form of the
erm
(B)- and
aphA3
-Containing Macrolide-Aminoglycoside-Streptothricin (MAS) Element
Authors: Palmieri Claudio , Mingoia Marina , Massidda Orietta , Giovanetti Eleonora , Varaldo Pietro E.
Published: August 2012

The macrolide-aminoglycoside-streptothricin (MAS) element, an ∼4.2-kb insertion containing
erm
(B) and
aphA3
resistance determinants, distinguishes
Streptococcus pneumoniae
transposon Tn
1545
/Tn
6003
from Tn
6002
. Here, it is shown to be an unstable genetic element that, although it lacks recombinase genes, can exploit long,
erm
(B)-containing direct repeats acting as
att
sites for spontaneous excision that may result in loss. Consequent to excision, which is RecA independent, Tn
1545
/Tn
6003
changes to Tn
6002
. In pneumococcal populations harboring Tn
1545
/Tn
6003
, the latter appears to coexist with Tn
6002
.
Cigarette Smoke Increases Staphylococcus aureus Biofilm Formation via Oxidative Stress
Authors: Kulkarni Ritwij , Antala Swati , Wang Alice , Amaral Fábio E. , Rampersaud Ryan , LaRussa Samuel J. , Planet Paul J. , Ratner Adam J.
Published: August 2012

The strong epidemiological association between cigarette smoke (CS) exposure and respiratory tract infections is conventionally attributed to immunosuppressive and irritant effects of CS on human cells. Since pathogenic bacteria such as
Staphylococcus aureus
are members of the normal microbiota and reside in close proximity to human nasopharyngeal cells, we hypothesized that bioactive components of CS might affect these organisms and potentiate their virulence. Using
Staphylococcus aureus
as a model organism, we observed that the presence of CS increased both biofilm formation and host cell adherence. Analysis of putative molecular pathways revealed that CS exposure decreased expression of the quorum-sensing
agr
system, which is involved in biofilm dispersal, and increased transcription of biofilm inducers such as
sarA
and
rbf
. CS contains bioactive compounds, including free radicals and reactive oxygen species, and we observed transcriptional induction of bacterial oxidoreductases, including superoxide dismutase, following exposure. Moreover, pretreatment of CS with an antioxidant abrogated CS-mediated enhancement of biofilms. Exposure of bacteria to hydrogen peroxide alone increased biofilm formation. These observations are consistent with the hypothesis that CS induces staphylococcal biofilm formation in an oxidant-dependent manner. CS treatment induced transcription of
fnbA
(encoding fibronectin binding protein A), leading to increased binding of CS-treated staphylococci to immobilized fibronectin and increased adherence to human cells. These observations indicate that the bioactive effects of CS may extend to the resident microbiota of the nasopharynx, with implications for the pathogenesis of respiratory infection in CS-exposed humans.
Galactose Metabolism Plays a Crucial Role in Biofilm Formation by Bacillus subtilis
Authors: Chai Yunrong , Beauregard Pascale B. , Vlamakis Hera , Losick Richard , Kolter Roberto
Published: August 2012

Galactose is a common monosaccharide that can be utilized by all living organisms via the activities of three main enzymes that make up the Leloir pathway: GalK, GalT, and GalE. In
Bacillus subtilis
, the absence of GalE causes sensitivity to exogenous galactose, leading to rapid cell lysis. This effect can be attributed to the accumulation of toxic galactose metabolites, since the
galE
mutant is blocked in the final step of galactose catabolism. In a screen for suppressor mutants restoring viability to a
galE
null mutant in the presence of galactose, we identified mutations in
sinR
, which is the major biofilm repressor gene. These mutations caused an increase in the production of the exopolysaccharide (EPS) component of the biofilm matrix. We propose that UDP-galactose is the toxic galactose metabolite and that it is used in the synthesis of EPS. Thus, EPS production can function as a shunt mechanism for this toxic molecule. Additionally, we demonstrated that galactose metabolism genes play an essential role in
B. subtilis
biofilm formation and that the expressions of both the
gal
and
eps
genes are interrelated. Finally, we propose that
B. subtilis
and other members of the
Bacillus
genus may have evolved to utilize naturally occurring polymers of galactose, such as galactan, as carbon sources.

IMPORTANCE
Bacteria switch from unicellular to multicellular states by producing extracellular matrices that contain exopolysaccharides. In such aggregates, known as biofilms, bacteria are more resistant to antibiotics. This makes biofilms a serious problem in clinical settings. The resilience of biofilms makes them very useful in industrial settings. Thus, understanding the production of biofilm matrices is an important problem in microbiology. In studying the synthesis of the biofilm matrix of
Bacillus subtilis
, we provide further understanding of a long-standing microbiological observation that certain mutants defective in the utilization of galactose became sensitive to it. In this work, we show that the toxicity observed before was because cells were grown under conditions that were not propitious to produce the exopolysaccharide component of the matrix. When cells are grown under conditions that favor matrix production, the toxicity of galactose is relieved. This allowed us to demonstrate that galactose metabolism is essential for the synthesis of the extracellular matrix.
The ‘impact’ of force filtering cut-off frequency on the peak knee abduction moment during landing: artefact or ‘artifiction’?
Authors: Roewer Benjamin D , Ford Kevin R , Myer Gregory D , Hewett Timothy E
Published: August 2012

Background

Joint moments computed using inverse dynamic techniques are important estimators of net joint loads. Joints moments computed from marker position and ground reaction force data filtered using different cut-off frequencies may capture changes in moment magnitudes at a single joint that exceed normal physiological response. Peak external knee abduction moment (KAM) generated during landing (ie, the drop vertical jump, DVJ) predicts anterior cruciate ligament injury risk using marker and force data filtered at different cut-off frequencies. The purpose of the current investigation was to determine the effects of using the same low cut-off frequencies versus different cut-off frequencies on joint moment magnitudes to evaluate if artificial smoothing attenuates actual resultant joint loads related to injury risk.

Methods

Twenty-two female, high school volleyball players performed three maximum DVJs in a laboratory setting. The average peak KAM was computed for each knee using marker and force data filtered with the same low cut-off frequencies and different cut-off frequencies.

Results

Peak KAMs were significantly larger using different cut-off frequencies. The order of athletes ranked based on the magnitude of their peak KAMs did not significantly change across all filtering cut-off frequencies.

Conclusions

The magnitude of peak KAM may differ when the same low or different higher cut-off frequencies are used to filter marker and ground reaction forces (GRF) data collected using standard motion capture equipment. It is not clear to what extent the decrease in peak KAM reported when the same low cut-off frequencies were used was solely due to attenuation of the GRF signal.
Six months fixed duration multidrug therapy in paucibacillary leprosy: risk of relapse and disability in Agra PB cohort study
Authors: Kumar Anil , Girdhar Anita , Girdhar Bhavneswar Kumar
Published: August 2012

Background

Many studies have focused on multidrug therapy (MDT) for multibacillary (MB) leprosy and rarely on long-term outcome of paucibacillary (PB) leprosy having recommendation of therapy for 6 months fixed duration therapy for PB patients. Studies on measuring risk of disability are rare. The present study is to assess the cure; default, relapse and disability in a prospective cohort of PB leprosy during follow-up of >4 years after treatment.

Design

Prospective.

Setting

Primary in our field area of Agra District.

Participants

920 PB leprosy patients entered the study, 621 completed treatment, 599 followed finally including 271 males, no ethnic differentiation, patients of all age groups except for children below 5 years and old persons above 70 years were not included.

Treatment

6 months fixed duration MDT as recommended by WHO.

Primary and secondary outcomes

Treatment completion, cure, relapse and development of disability based on clinical assessment by well-experienced doctors.

Statistical methods

Data have been analysed using SPSS software, risk is computed as incidence per 100 person–years (PY) and test of significance used.

Results

Study reports 91% cure rate. Incidence of relapse was 1.3/100 PY with no significant variation by age, sex, delay in detection, patches and nerves. Crude incidence of disability was 2.2% and varied significantly by age and nerve thickening but not by sex, number of patches, nerves and delay in treatment. Incidence of disability was 0.50/100 PY in treatment completed and 0.43 among defaulters.

Conclusion

The study concludes that relapses do occur after MDT treatment but at the level of 1–2%, incidence of disability remains low (<1/100 PY) in PB leprosy. Low incidence of relapse and disability suggests that 6 months therapy is quite effective. However, further improvement may help to improve its efficacy. Longer follow-up may add to efficacy measures.
Prevalence and persistence of depression among undergraduate medical students: a longitudinal study at one UK medical school
Authors: Quince Thelma A , Wood Diana F , Parker Richard A , Benson John
Published: August 2012

Objectives

To determine the prevalence of depression among male and female medical students, its change over time and whether depression persists for affected students.

Design

Longitudinal study comprising annual questionnaire surveys which included the depression subscale of the Hospital Anxiety and Depression Scale (HADS-D).

Participants

Between 2007 and 2010 all 1112 students entering the Core Science component (Year 1) and all 542 students entering the Clinical component (Year 4) of the Cambridge (UK) medical course were followed-up annually.

Methods

We analysed, separately for men and women, mean HADS-D scores, the proportions whose scores indicated depression at different time-points and for students maintaining participation, the number of occasions on which their HADS-D scores indicated depression.

Results

725 Core Science and 364 Clinical students participated. Mean HADS-D scores ranged between 3.34 and 3.49 among all Core Science students and between 2.16 and 2.91 among all Clinical students. There was no difference between men and women in median HADS-D scores. Prevalence of depression ranged between 5.7% and 10.6% among all Core Science students and between 2.7% and 8.2% among all Clinical students.

Over time Core Science students displayed no increase in mean HADS-D score. Among Clinical students only men displayed a small increase (time coefficient 0.33 (95% CI 0.11 to 0.55)). Prevalence did not increase over time. 220 Core Science and 150 Clinical students participated throughout the study. Of these, 18.2% and 10.6%, respectively, recorded HADS-D scores indicating depression on at least one occasion. Of 56 students recording depression at some point, 37 did so only once.

Conclusions

Prevalence of depression among participants was similar to that reported for comparable groups. Among men approaching the end of clinical studies depression scores increased. In all years a minority of students displayed depression; for some this persisted. Mechanisms are needed to identify and support students suffering from depression, particularly when persistent.
A review of qualitative methodologies used to explore patient perceptions of arts and healthcare
Authors: Moss Hilary , Donnellan Claire , O'Neill Desmond
Published: August 2012

Although the importance of the arts in healthcare is increasingly recognised, further research is needed to investigate the mechanisms by which arts and health programmes achieve their impact. An overview of the qualitative methods used to explore patients' perceptions of these interventions is lacking. We reviewed the literature to gain insights into the qualitative methods used to explore patients' perceptions of the role of arts in healthcare with a view to identifying the most common methodologies used and to guide researchers embarking on research regarding patients' perceptions of arts in healthcare. Our results indicate a paucity of qualitative studies, a variety of methods used and variability of methodological rigour. Grounded theory and phenomenology were the most common approaches adopted, mixed methods approaches were relatively frequent, and versions of ‘thematic’ or ‘content’ analysis were commonly cited. Semi-structured interviews were the most popular data collection method. The emphasis of all of the studies was on active or participative arts engagement, with no focus on receptive engagement with the arts and aesthetics. It was concluded that careful consideration of appropriate methodology is important when researching such an exploratory and sensitive area. Individual interviews were most popular and might be appropriate when exploring personal, sensitive experiences. Mixed method studies possibly provide a comprehensive approach which might satisfy both the arts and healthcare settings need for evidence. It seems important to pay attention to rigour in any methodology chosen and a greater focus on receptive engagement with the arts might be encouraged in future research.
Stent assisted coil embolization of wide-necked bilobed anterior inferior cerebellar artery aneurysm with incorporated artery arising from the dome: a technical note
Authors: Sabharwal Paramveer Singh , Saini Jitender , Hanumanthapura Ramalingaiah Arvinda
Published: August 2012

Background

A technique for stent-assisted coil embolization of a bilobed wide-necked saccular aneurysm of the anterior inferior cerebellar artery (AICA) with the AICA arising from the dome of the aneurysm is described.

Clinical presentation

A middle-aged patient was referred for treatment of a bilobed saccular aneurysm identified on a CT angiogram performed for a subarachnoid hemorrhage which occurred 20 days prior to presentation. A diagnostic angiogram showed a bilobed wide-necked saccular aneurysm at the AICA origin with the AICA arising from the dome of the aneurysm and also supplying the territory of the posterior inferior cerebellar artery. The therapeutic procedure involved trans-aneurysmal cannulation of the AICA with the microcatheter left in situ. Another microcatheter was maneuvered into the larger dome of the aneurysm. A stent was then deployed in the basilar artery, jailing the previous microcatheter in the aneurysm. Helical Guglielmi detachable coils were deployed in the aneurysm resulting in complete occlusion of the aneurysm with preservation of the AICA.

Conclusions

It is important to preserve a normal branch arising from the dome of an aneurysm although it is technically demanding and a relative limitation. This case report describes a technique of coiling a bilobed aneurysm with a vital branch arising from the dome, with preservation of the branch and complete occlusion of the aneurysm using two microcatheters and a stent. This expands the repertoire of endovascular treatment of complex aneurysms.
Herbal Medicines as Adjuvants for Cancer Therapeutics
Authors: Wang Chong-Zhi , Calway Tyler , Yuan Chun-Su
Published: August 2012

In the United States, many patients, including cancer patients, concurrently take prescription drugs and herbal supplements. Co-administration of prescription medicines and herbal supplements may have negative outcomes via pharmacodynamic and pharmacokinetic herb-drug interactions. However, multiple constituents in botanicals may also yield beneficial pharmacological activities. Botanicals could possess effective anticancer compounds that may be used as adjuvants to existing chemotherapy to improve efficacy and/or reduce drug-induced toxicity. Herbal medicines, such as ginseng, potentiated the effects of chemotherapeutic agents via synergistic activities, supported by cell cycle evaluations, apoptotic observations, and computer-based docking analysis. Since botanicals are nearly always administrated orally, the role of intestinal microbiota in metabolizing ginseng constituents is presented. Controlled clinical studies are warranted to verify the clinical utility of the botanicals in cancer chemoprevention.
Self-Reported Knowledge and Approaches Toward Complementary and Alternative Medicine Among Physicians Dealing with Allergic Diseases
Authors: Argüder Emine , Yılmaz İnsu , Ateş Can , Mısırlıgil Zeynep , Bavbek Sevim
Published: August 2012

Considering the popularity of Complementary and Alternative Medicine (CAM) in allergic patients, physicians involved in allergic patients' care need to be aware of CAM. To assess self-reported knowledge, attitude and approach to CAM of physicians who deal with allergic patients, a total of 500 structured questionnaires were distributed to physicians who participated in "Turkish National Society of Allergy and Clinical Immunology Congress-2009". For the questionnaires handed out, 242 (48.4%) physicians (median age 36.0 years, range 25–64 years) responded; 22.4% were fellows in training and 48.5% were residents. The main specialties were pediatrics (49.3%), and pulmonology (36.8%); half were either specialists or training in allergy and one-quarter (25.6%) referred patients to CAM. Asthma (42.1%) and chronic urticaria (28.9%) were the most common CAM referral diseases. Referred therapies were herbal (10.3%) and diet-based medicine (7.4%). The differences between physicians in terms of age, gender, experience in medicine, and specialty/allergy subspecialty were not statistically significant (p = 0.01). Affiliation to a university hospital was significantly associated with no CAM referral vs. affiliation in a state/private hospital or private practice. Academic degree and reported level of knowledge negatively/positively affected attitudes toward CAM, respectively. More than half of the respondents (68.8%) reported lack of or insufficient information about CAM, while 58.7% of physicians desired CAM education. This first report on physicians involved in allergic patients' care shows that they are reluctant to refer for CAM therapies. A minority believes that they have enough knowledge, and most are interested in continuing medical education on CAM. Considering physicians' interest and tendency to communicate significantly with their patients about CAM when they feel that they have sufficient knowledge and popularity of CAM among patients, training possibilities should be created to improve physicians' education in this field.
Efficacy of Two Different Materials used in Auricular Acupressure on Weight Reduction and Abdominal Obesity
Authors: Hsieh Ching Hsiu , Su Tsann-Juu , Fang Yu-Wen , Chou Pei-Hsuan
Published: August 2012

The current study was designed to test the efficacy of different materials used in an auricular acupressure program on weight reduction, changes to waist circumference and waist-to-hip ratio. This study used a randomized design with two groups who were treated with auricular acupressure using Semen Vaccariae or the Japanese Magnetic Pearl. Both groups consisted of Asian young adults with a waist circumference ≥ 80 cm in the females and ≥ 90 cm in the males. At completion of the eight-week treatment period, the total sample size was 56 young adults who ranged in age from 18 to 20 years old. Each participant was met with weekly for ten-minute sessions during which ear acupressure treatment was performed. Sessions continued for eight weeks wherein both groups received acupressure with the Japanese Magnetic Pearl or Semen Vaccariae on the ear acupoints. While both groups showed significant reductions (p ≤ 0.05) to body weight and waist circumference after eight weeks of treatments, the group treated with Semen Vaccariae group showed a more effective weight loss over the short term. Given that auricular acupressure is a safe and cost-effective treatment for weight loss, our results suggest that auricular acupressure is a reasonable option for the treatment of overweight and obesity in young adults.
Fermentation Improves Anti-Inflammatory Effect of Sipjeondaebotang on LPS-Stimulated RAW 264.7 Cells
Authors: Oh You-Chang , Cho Won-Kyung , Jeong Yun Hee , Im Ga Young , Yang Min Cheol , Ma Jin Yeul
Published: August 2012

Sipjeondaebotang (SJ) has been used as a traditional drug in east-Asian countries. In this study, to provide insight into the biological effects of SJ and SJ fermented by Lactobacillus, we investigated their effects on lipopolysaccharide (LPS)-mediated inflammation in macrophages. The investigation was focused on whether SJ and fermented SJ could inhibit the production of pro-inflammatory mediators such as prostaglandin (PG) E2and nitric oxide (NO) as well as the expressions of cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS), tumor necrosis factor (TNF)-α, mitogen-activated protein kinases (MAPKs) and nuclear factor (NF)-κB in LPS-stimulated RAW 264.7 cells. We found that SJ modestly inhibited LPS-induced PGE2, NO and TNF-α production as well as the expressions of COX-2 and iNOS. Interestingly, fermentation significantly increased its inhibitory effect on the expression of all pro-inflammatory mediators. Furthermore, fermented SJ exhibited increased inhibition of p38 MAPK and c-Jun NH2-terminal kinase (JNK) MAPK phosphorylation as well as NF-κB p65 translocation by reduced IκBα degradation compared with either untreated controls or unfermented SJ. High performance liquid chromatography (HPLC) analysis showed fermentation by Lactobacillus increases liquiritigenin and cinnamyl alcohol contained in SJ, which are known for their anti-inflammatory activities. Finally, SJ fermented by Lactobacillus exerted potent anti-inflammatory activity by inhibiting MAPK and NF-κB signaling in RAW 264.7 cells.
Immunomodulatory Effects of Aqueous and Organic Fractions from Petiveria alliacea on Human Dendritic Cells
Authors: Santander Sandra Paola , Hernández John Fredy , Cifuentes B Claudia , Aoki Masayuki , Moins-Teisserenc Helene , Fiorentino Susana
Published: August 2012

Petiveria alliacea is a plant traditionally known for its anti-inflammatory and anti-tumor activities; however, the molecular and cellular mechanisms of its immunomodulatory properties are still unknown. Dendritic cells (DC) promote adaptive immune response by activating T lymphocytes, inducing an effector response or tolerance depending on the DC differentiation level. Herein, we evaluated the immunomodulatory activity of aqueous and organic plant fractions from P. alliacea using human monocyte-derived dendritic cells. The phenotype, cytokine secretion and gene expression were estimated after treatment with the plant fractions. We found that P. alliacea aqueous fraction induced morphological changes and co-stimulatory expression of CD86, indicating partial DC maturation. In addition, pro-inflammatory cytokines such as IL-1β, IL-6, IL-8, IL-10, IL-12p70, and TNF-α were secreted. The fraction also increased NF-κB gene expression while down-regulating TGFβ gene expression. These results suggest that the aqueous fraction can induce partial DC activation, a situation that can be relevant in tolerance induction. It is important to state that the organic fraction by itself does not show any immunomodulatory activity. This study provides evidence for possible immunomodulatory activity of P. alliacea extracts which has been used in traditional medicine in Colombia.
ISSUES WITH VACUUM ENERGY AS THE ORIGIN OF DARK ENERGY
Authors: ZIAEEPOUR HOURI
Published: August 2012

In this paper, we address some of the issues raised in the literature about the conflict between a large vacuum energy density, a priori predicted by quantum field theory, and the observed dark energy which must be the energy of vacuum or include it. We present a number of arguments against this claim and in favor of a null vacuum energy. They are based on the following arguments: A new definition for the vacuum in quantum field theory as a frame-independent coherent state; results from a detailed study of condensation of scalar fields in Friedmann–Lemaître–Robertson–Walker (FLRW) background performed in a previous work; and our present knowledge about the Standard Model of particle physics. One of the predictions of these arguments is the confinement of nonzero expectation value of Higgs field to scales roughly comparable with the width of electroweak gauge bosons or shorter. If the observation of Higgs by the LHC is confirmed, accumulation of relevant events and their energy dependence in near future should allow us to measure the spatial extend of the Higgs condensate.
RESONANCES IN SYSTEMS WITH TWO DIFFERENT TYPES OF HEAT TRANSFER
Authors: NEMCHENKO K. , ROGOVA S.
Published: August 2012

Heat transfer in double-layer systems with superfluid helium as one of the layers is studied in this paper. Double-layer systems like heater-helium and helium-detector were considered. The limiting cases of the relation of the non-helium layer length and the length of the heat wave in it were investigated. The unusual resonances were found in the double-layer system helium-detector. Analytical expressions for width and amplitudes of these resonances were obtained. At the same time it was found that the resonance width in helium can be determined not by the dissipative properties of helium, but by the thermodynamic parameters of the detector.
EFFECTS OF POST-ANNEALING ON THE MICROSTRUCTURAL AND ELECTRICAL PROPERTIES OF AMORPHOUS LaAlO3 FILM GROWN ON Si
Authors: LIU B. T. , ZHANG X. G. , YANG L. , LI M. , DAI P. C. , CHEN J. H. , MA L. X.
Published: August 2012

10-nm-thick amorphous LaAlO 3 film was deposited on n-type Si (001) substrate at 600°C by magnetron sputtering and then annealed in N 2 ambience at 300°C for 2 min using a rapid thermal annealing furnace. Grazing incidence X-ray diffraction analyses indicated that the post-annealed LaAlO 3 film was still amorphous. The root-mean-square roughness of the post-annealed sample is a little smaller than that of the as-grown sample, which could stem from the densification of LaAlO 3 film after post-annealing. No obvious hysteretic behavior was observed in the capacitance–voltage measurement and the dielectric constant of LaAlO 3 film was estimated to be 16.7. Due to the deficiency of oxygen vacancy after post-annealing, the low leakage current density of the post-annealed film with EOT of 2.33 nm is about 5.52 × 10-5 A/cm2 at +1 MV/cm. Moreover, it is found that both the as-grown and post-annealed capacitors satisfy Ohmic conduction behavior at the whole positive measured electric fields.
SEPARATION OF RESONANCE MODES IN NANORING RESONATOR BY A CASCADED SLOT CAVITY
Authors: SHANG KEFENG , YAN LIANSHAN , WEN KUNHUA , GUO ZHEN , GUO YINGHUI , PAN WEI , LUO XIANGANG
Published: August 2012

A mode separation approach in the nanoring resonator by a cascaded slot cavity is proposed and numerically investigated using the finite-difference time-domain (FDTD) method. With the cascaded slot cavity, the specified modes in the nanoring can be separated to realize a wide free spectral range (FSR) or single channel filtering, which provides a free degree to the plasmonic filters design. Simulation results also demonstrate that the full-width at half-maximum (FWHM) of the single channel filter obtained from the cascaded slot cavity can be effectively reduced to meet various requirements.
UML REPRESENTATION FOR RULE-BASED APPLICATION MODELS WITH XTT2-BASED BUSINESS RULES
Authors: NALEPA GRZEGORZ J. , KLUZA KRZYSZTOF
Published: August 2012

In this paper challenges of using Knowledge Engineering methods in the Software Engineering practice, with focus on the visual design methods for software applications, are discussed. The paper concerns practical design issues of rule-based models integrated with business applications built using the Model-View-Controller (MVC), or equivalent architectural pattern. The Unified Modeling Language (UML) constitutes a standardized notation among software engineers. Various attempts has been made to design the model in a way alternative to UML. Recently, the Business Rules approach has been proposed as a new way of capturing the functional requirements in a designer-friendly fashion. However, concepts on which the rule-based representation is based cannot be directly modeled in UML, because the semantics of UML diagrams does not correspond to rule semantics. Our research considers a method of designing rule bases which will be proper and consistent with the UML design. The approach has several important features: the core logic of the application is clearly identified and separated, and it is built in a declarative way, which makes the design transparent, easier to follow and develop. When rules are used to model the application logic, one has to keep in mind some common and well-known limitations of the existing rule tools. Our solution to these problems consists of using an expressive visual rule design formalism called XTT2, defining a direct translation between XTT2 and selected UML diagrams, implementing practical translators between the logical model and MOF-based UML model, and using the verification features provided with the XTT2 framework to assure the quality of the rule base. This solution seems to be superior both to existing visual UML rule notations, as well as visual design tools for rules. It does not extend any custom UML artifacts and can be used with standard UML tools.
AN EMPIRICAL STUDY OF SOFTWARE METRICS FOR ASSESSING THE PHASES OF AN AGILE PROJECT
Authors: CONCAS GIULIO , MARCHESI MICHELE , DESTEFANIS GIUSEPPE , TONELLI ROBERTO
Published: August 2012

We present an analysis of the evolution of a Web application project developed with object-oriented technology and an agile process. During the development we systematically performed measurements on the source code, using software metrics that have been proved to be correlated with software quality, such as the Chidamber and Kemerer suite and Lines of Code metrics. We also computed metrics derived from the class dependency graph, including metrics derived from Social Network Analysis. The application development evolved through phases, characterized by a different level of adoption of some key agile practices — namely pair programming, test-based development and refactoring. The evolution of the metrics of the system, and their behavior related to the agile practices adoption level, is presented and discussed. We show that, in the reported case study, a few metrics are enough to characterize with high significance the various phases of the project. Consequently, software quality, as measured using these metrics, seems directly related to agile practices adoption.
MOLECULAR DYNAMICS SIMULATION OF THE ADSORPTION AND DIFFUSION OF A SINGLE POLYDIMETHYLSILOXANE POLYMER CHAIN ON A SILICON (111) SURFACE
Authors: MU DAN , LI JIAN-QUAN , WANG SONG , WANG JIAN-FENG
Published: August 2012

The adsorption of polydimethylsiloxane (PDMS) single chain with different chain lengths on a silicon (111) surface were studied by molecular dynamics simulations. The relative dielectric constant was selected to be 1 and 78.0 to mimic in vacuum and in solution environment, respectively. The chains were all present as two-dimensional (2D) adsorption conformation on the surface but different conformations and dynamic properties were found in the two absolutely different environments. The relationship between the adsorption energy of the different chain lengths and the degree of polymerization follows a linear function and the average adsorption energy per segment is -0.42 kcal/mol. In addition, the diffusion coefficient (D) of such chains scales with the degree of polymerization (N) as N-3/2.
INFLUENCE OF VIBRATIONAL EXCITATION AND COLLISION ENERGY ON THE STEREO DYNAMICS OF THE REACTIONS:N(4S)+H2(v = 0-3,j = 0) →NH(X3Σ-)+H
Authors: YU YONG-JIANG , WANG DE-HUA , FENG SHU-XIANG , XIA WEN-ZE
Published: August 2012

Quasi-classical trajectory (QCT) calculations have been carried out to study the stereodynamics of the title reactions, using the double many-body expansion (DMBE) potential energy surface (PES) constructed by Poveda [Poveda LA, Varandas AJC, Phys. Chem. Chem. Phys.7:2867, 2005]. Vector correlations, such as the distributions of the polarization-dependent differential cross-sections (PDDCSs), the angular distributions of P(θr), P(ϕr), P(θr,ϕr), and the product alignment parameter P2( cos θr) are reported within the energy range of 25–140 kcal mol-1. The influences of the collision energy and the initial state-selected vibrational excitation are discussed in detail. In addition, Validity of the current QCT calculations is also examined and compared with the revelant results reported by Pascual et al. [Pascual RZ, Schatz GC, Lendvay G, Troya D, J. Phys. Chem. Aਠ106:4125, 2002].
HOMOLOGY MODELING AND SUBSTRATE BINDING STUDY OF HUMAN KYNURENINE AMINOTRANSFERASE III
Authors: XU YU , ZHENG QING-CHUAN , ZHANG HONG-XING , SUN CHIA-CHUNG
Published: August 2012

Kynurenine aminotransferase III (KAT III) is a novel member of the kynurenine aminotransferase enzyme family. Its active site topology and structure characteristics have not been established. In this study, with extensive computational simulations, including homology modeling and molecular dynamics simulations, a 3D structure model of human KAT III dimer was created and refined. Furthermore, CDOCKER approach was employed to dock two ligands (L-methionine and L-tryptophan) into the active sites of human KAT III dimer and uncover the ligand-binding modes. The complexes were subjected to 5 ns MD simulation, and the results indicate that TYR119 and TRP13 might be the key residues as they have the large contributions to the binding affinity, which is in good agreement with the experimental results. Moreover, another two residues (ASP120 and TYR57) are also found that their strong interactions stabilize the whole system. The structural and biochemical insights obtained from the present study will be helpful for designing the specific inhibitors of human KAT III.
THE IMPACT OF THE US RECESSION ON IMMIGRANT REMITTANCES IN CENTRAL AMERICA
Authors: BORJA KARLA
Published: August 2012

The United States (US) economic recession has considerably affected employment among its immigrant Hispanic community, and as a consequence, remittances to Central America have plunged more than in any other region in the world. This paper provides evidence that the US housing crisis and the subsequent economic recession have affected the Central American region's Gross Domestic Product (GDP) beyond the traditional means of exports, exchange rates, and interest rates, namely, through remittances as well. Using a Vector Autoregression (VAR) model, we examine the case of El Salvador and find that major disturbances to the US economy have an immediate and substantial impact on remittances to this Central American nation.
Evaluating Late Holocene radiocarbon-based chronologies by matching palaeomagnetic secular variations to geomagnetic field models: an example from Lake Kalimpaa (Sulawesi, Indonesia)
Authors: Haberzettl Torsten , St-Onge Guillaume , Behling Hermann , Kirleis Wiebke
Published: August 2012

Palaeomagnetic and palaeoenvironmental data from Indonesia and particularly from the Island of Sulawesi are scarce and exact dating has turned out to be a challenge in many archives from this region. Here we outline difficulties in radiocarbon dating of the palaeoenvironmental record from Lake Kalimpaa, Sulawesi, Indonesia. These difficulties demand the integration of additional parameters to obtain a reliable chronology for this record. Thus, we compare the palaeomagnetic secular variation data from this record with the CALS3k.4 spherical harmonic geomagnetic model of the 0–3 ka field (
Korte & Constable 2011
). The resulting age–depth model for the Lake Kalimpaa sequence provides a profound basis for further multi-proxy investigations on this record. For the first time, high-resolution palaeomagnetic secular variation data continuously spanning the past 1300 years are presented for this region, which complement existing records with lower temporal resolution or records missing the top-most sections.
Visual identification and quantification of Milankovitch climate cycles in outcrop: an example from the Upper Ordovician Kope Formation, Northern Kentucky
Authors: Ellwood Brooks B. , Brett Carlton E. , Tomkin Jonathan H. , Macdonald William D.
Published: August 2012

Applying time-series analyses using Fourier transform and multi-taper methods to low-field, mass-specific magnetic susceptibility (χ) measurements on marine samples from well-studied shale and limestone outcrops of the Upper Ordovician (Edenian Stage; Upper Katian) Kope Formation, northern Kentucky, corroborates direct visual identification in outcrops of Milankovitch eccentricity (
c.
405 and 100 ka), obliquity and precessional climate cycles. Because individual outcrops were too short and deposition too chaotic to yield significant time-series results, it was necessary to build a
c.
50 m thick composite sequence from three well-correlated outcrops to quantify the cyclicity. Time-series analysis was then performed using χ measured for 1004 closely spaced samples covering the section. Milankovitch bands are recorded in the time-series data from the composite. We tested this result by comparison of these bands to cyclic packages in outcrop, which correspond to thicknesses represented in the time-series datasets. This is particularly well defined for the eccentricity and obliquity cycles, with precessional bands being evident but as less well-defined packages of beds.
Rock-magnetic cyclostratigraphy for the Late Pliocene–Early Pleistocene Stirone section, Northern Apennine mountain front, Italy
Authors: Gunderson Kellen L. , Kodama Kenneth P. , Anastasio David J. , Pazzaglia Frank J.
Published: August 2012

Lithostratigraphic, magnetostratigraphic and rock-magnetic cyclostratigraphic data were combined to create a high-resolution age model for 342 m of Late Pliocene–Middle Pleistocene marine deposits exposed in the Stirone River, northern Italy. Magnetostratigraphic analysis of 74 oriented samples at 21 stratigraphic horizons recognized five polarity zones between
c.
3.0 and 1.0 Ma. Unoriented samples were collected every metre between 0 and 311 m and low-field magnetic susceptibility (
χ
) was measured for cyclostratigraphic analysis. The
χ
data series was tied to absolute time using the magnetostratigraphy and subjected to multi-taper method spectral analysis. The resultant power spectra revealed significant frequency peaks that are aligned with eccentricity, obliquity and precession Milankovitch orbital cycles. The
χ
data, correlated to the 41 ka obliquity and the 23 ka/19 ka precession cycles and anchored to a well-established biostratigraphic horizon, were used to create a high-resolution age model for the Stirone section between 2.99 and 1.81 Ma, where stratigraphic positions of magnetic reversals were previously poorly defined. This cyclostratigraphic age model reveals that the length of an important depositional hiatus at the base of the C2An.1n subchron is 200 ka shorter than previously determined. We link the precession-aligned variability in
χ
to global mid-latitude, insolation-induced variability in runoff and ocean circulation.
Cellular cross-talk between epicardial adipose tissue and myocardium in relation to the pathogenesis of cardiovascular disease
Authors: Cherian Sam , Lopaschuk Gary D. , Carvalho Eugenia
Published: August 2012

Epicardial and perivascular fat depot size is considered an index of cardiac and visceral obesity. The functional and anatomic proximity of epicardial adipose tissue (EAT) to myocardium has drawn increasing attention in recent years among researchers attempting to elucidate its putative role as an endocrine organ. This includes the role of EAT as a lipid storing depot and as an inflammatory tissue secreting cytokines and chemokines under pathogenic conditions such as cardiovascular diseases. In this review, we discuss the current state of knowledge regarding the potential EAT mediators of inflammation and the paracrine cross-talk between EAT and the underlying myocardium. We also highlight the most recent findings on the causes and correlates of myocardial steatosis/cardiac lipotoxicity and its association with cardiac dysfunction.
Hyperammonemia-mediated autophagy in skeletal muscle contributes to sarcopenia of cirrhosis
Authors: Qiu Jia , Tsien Cynthia , Thapalaya Samjhana , Narayanan Arvind , Weihl Conrad Chris , Ching James K. , Eghtesad Bijan , Singh Kamini , Fu Xiaoming , Dubyak George , McDonald Christine , Almasan Alex , Hazen Stanley L. , Naga Prasad Sathyamangla V. , Dasarathy Srinivasan
Published: August 2012

Hyperammonemia and sarcopenia (loss of skeletal muscle) are consistent abnormalities in cirrhosis and portosystemic shunting. We have shown that muscle ubiquitin-proteasome components are not increased with hyperammonemia despite sarcopenia. This suggests that an alternative mechanism of proteolysis contributes to sarcopenia in cirrhosis. We hypothesized that autophagy could be this alternative pathway since we observed increases in classic autophagy markers, increased LC3 lipidation, beclin-1 expression, and p62 degradation in immunoblots of skeletal muscle protein in cirrhotic patients. We observed similar changes in these autophagy markers in the portacaval anastamosis (PCA) rat model. To determine the mechanistic relationship between hyperammonemia and autophagy, we exposed murine C2C12 myotubes to ammonium acetate. Significant increases in LC3 lipidation, beclin-1 expression, and p62 degradation occurred by 1 h, whereas autophagy gene expression (LC3, Atg5, Atg7, beclin-1) increased at 24 h. C2C12 cells stably expressing GFP-LC3 or GFP-mCherry-LC3 constructs showed increased formation of mature autophagosomes supported by electron microscopic studies. Hyperammonemia also increased autophagic flux in mice, as quantified by an in vivo autophagometer. Because hyperammonemia induces nitration of proteins in astrocytes, we quantified global muscle protein nitration in cirrhotic patients, in the PCA rat, and in C2C12 cells treated with ammonium acetate. Increased protein nitration was observed in all of these systems. Furthermore, colocalization of nitrated proteins with GFP-LC3-positive puncta in hyperammonemic C2C12 cells suggested that autophagy is involved in degradation of nitrated proteins. These observations show that increased skeletal muscle autophagy in cirrhosis is mediated by hyperammonemia and may contribute to sarcopenia of cirrhosis.
Reproductive Counseling by Clinic Healthcare Workers in Durban, South Africa: Perspectives from HIV-Infected Men and Women Reporting Serodiscordant Partners
Authors: Matthews L. T. , Crankshaw T. , Giddy J. , Kaida A. , Psaros C. , Ware N. C. , Smit J. A. , Bangsberg D. R.
Published: August 2012

Background. Understanding HIV-infected patient experiences and perceptions of reproductive counseling in the health care context is critical to inform design of effective pharmaco-behavioral interventions that minimize periconception HIV risk and support HIV-affected couples to realize their fertility goals.Methods. We conducted semistructured, in-depth interviews with 30 HIV-infected women (with pregnancy in prior year) and 20 HIV-infected men, all reporting serodiscordant partners and accessing care in Durban, South Africa. We investigated patient-reported experiences with safer conception counseling from health care workers (HCWs). Interview transcripts were reviewed and coded using content analysis for conceptual categories and emergent themes.Results. The study findings indicate that HIV-infected patients recognize HCWs as a resource for periconception-related information and are receptive to speaking to a HCW prior to becoming pregnant, but seldom seek or receive conception advice in the clinic setting. HIV nondisclosure and unplanned pregnancy are important intervening factors. When advice is shared, patients reported receiving a range of information. Male participants showed particular interest in accessing safer conception information.Conclusions. HIV-infected men and women with serodiscordant partners are receptive to the idea of safer conception counseling. HCWs need to be supported to routinely initiate accurate safer conception counseling with HIV-infected patients of reproductive age.