bluuebunny/crossref_metadata_2025 huggingface dataset:
High Speed SPM Applied for Direct Nanoscale Mapping of the Influence of Defects on Ferroelectric Switching Dynamics
Authors: Huey Bryan D. , Nath Premnath Ramesh , Lee Sungjun , Polomoff Nicholas A.
Published: March 2012

A high speed variation of Scanning Probe Microscopy with continuous image rates on the order of 1 frame per second is applied to investigate the nucleation and growth of individual ferroelectric domains. Movies of consecutive images directly identify nascent domains and their nucleation times, while tracking their development with time and voltage reveals linear domain growth at lateral velocities near 1 mm/s, even faster for nascent domains. Nanoscale maps of nucleation times and growth velocities indicate that domain nucleation and growth are uncorrelated, varying extensively with position. Domain switching dynamics do strongly couple to film defects; for instance, grain boundaries can profoundly pin domain walls, and polarization reversal kinetics are influenced by strain fields near microcracks or in asymmetric specimens. The influence of the onset of switching fatigue is observed as well. These results highlight the importance of updating classical interpretations of ferroelectric switching for truly rigorous models of polarization dynamics. Coupling high speed SPM imaging with in situ activation by voltage or other parameters therefore provides an important methodology to research dynamic surface properties with nanoscale resolution, extendable to a range of materials such as photovoltaics, thermoelectrics, batteries, fuel cells, multiferroics, phase change systems, etc.
Prevalence of peri‐implant diseases. A cross‐sectional study based on a private practice environment
Authors: Mir‐Mari Javier , Mir‐Orfila Pedro , Figueiredo Rui , Valmaseda‐Castellón Eduard , Gay‐Escoda Cosme
Published: March 2012

Aim

To determine the prevalence of peri‐implant diseases in private practice patients enrolled in a periodontal maintenance programme.

Material and Methods

A cross‐sectional study was carried out in patients with dental implants attending the dental clinic to comply with a periodontal maintenance programme between January and June 2010. Implants with at least 1 year of loading time (range: 1–18 years) were included. A patient‐based prevalence analysis of peri‐implant diseases was carried out. Additionally, implants were classified into the following categories: healthy, clinically stable, mucositis and peri‐implantitis.

Results

A total of 245 patients (964 dental implants) were analysed. Implant and patient‐based peri‐implantitis prevalences were 9.1% [95% confidence interval (95%CI): 7.5–11.1%] and 16.3% [95%CI: 12.2–21.5%] respectively. Mucositis affected 21.6% [95%CI: 19.1–24.5%] of the studied implants and 38.8% [95%CI: 33.3–45.4%] of the patients.

Conclusions

The prevalence of peri‐implantitis in private practice patients enrolled in a periodontal maintenance programme was estimated to be between 12% and 22%. Almost 40% of the patients had mucositis. These prevalences are similar to those published in University environment samples.
S3 – Guidelines on the treatment of psoriasis vulgaris (English version). Update
Authors: Nast Alexander , Boehncke Wolf‐Henning , Mrowietz Ulrich , Ockenfels Hans‐Michael , Philipp Sandra , Reich Kristian , Rosenbach Thomas , Sammain Adel , Schlaeger Martin , Sebastian Michael , Sterry Wolfram , Streit Volker , Augustin Matthias , Erdmann Ricardo , Klaus Joachim , Koza Joachim , Muller Siegrid , Orzechowski Hans‐Dieter , Rosumeck Stefanie , Schmid‐Ott Gerhard , Weberschock Tobias , Rzany Berthold
Published: March 2012

Psoriasis vulgaris is a common and often chronic inflammatory skin disease.The incidence of psoriasis in Western industrialized countries ranges from 1.5% to 2%. Patients afflicted with severe psoriasis vulgaris may experience a significant reduction in quality of life. Despite the large variety of treatment options available, surveys have shown that patients still do not received optimal treatments. To optimize the treatment of psoriasis in Germany, the Deutsche Dermatologi sche Gesellschaft (DDG) and the Berufsverband Deutscher Dermatologen (BVDD) have initiated a project to develop evidence‐based guidelines for the management of psoriasis. They were first published in 2006 and updated in 2011. The Guidelines focus on induction therapy in cases of mild, moderate and severe plaque‐type psoriasis in adults including systemic therapy, UV therapy and topical therapies.

The therapeutic recommendations were developed based on the results of a systematic literature search and were finalized during a consensus meeting using structured consensus methods (nominal group process).
Testicular torsion: a 15‐year single‐centre clinical and histological analysis
Authors: Saxena AK , Castellani C , Ruttenstock EM , Höllwarth ME
Published: March 2012

Aim:  This study reviewed the demographic, epidemiological and clinical factors of boys seen at a single centre who underwent surgical exploration for testicular torsion.

Methods:  Retrospective single‐centre review of boys with testicular torsion between 1996 and 2011 was made.

Results:  Testicular torsion (right n = 43, left n = 60, bilateral n = 1) was identified in 104 boys between 0 and 18 years. Ten newborns presented with 11 intrauterine torsions. Nine torsions presented in undescended inguinal testes (one intrauterine). In 94 boys with descended testes, presentation included pain (76%), scrotal swelling (65%) and abdominal symptoms (22%). Ultrasonography was performed in 85 patients with false‐negative results in 4 (4.7%). Orchiectomy was performed during initial exploration in 41, with significantly higher rates of orchiectomies in patients with late (>6 h) versus patients with early referrals (<6 h) (56% vs. 9.1%). Histological evaluation was carried out in 68 testes, with 43 resected testes demonstrating haemorrhagic necrosis. In 25 biopsied testes, histology revealed acute parenchymal bleeding (n = 14), onset of parenchymal infarction (n = 8), orchitis (n = 1) and normal tissue (n = 2). Eighty‐two patients were followed up with pathological findings in four patients: testicular atrophies requiring orchiectomy (n = 2), testicular autolysis (n = 1) and small testicular vein thrombosis (n = 1).

Conclusion:  Chances of testicular salvage after torsion are higher if patients present early. The majority of patients presenting late (>6 h) require orchiectomy owing to testicular necrosis.
Diabetes, coeliac disease, multiple sclerosis and chronic arthritis in first‐degree relatives of patients with juvenile idiopathic arthritis
Authors: Pohjankoski Heini , Kautiainen Hannu , Kotaniemi Kaisu , Korppi Matti , Savolainen Anneli
Published: March 2012

Aim:  To evaluate the occurrence of autoimmune diseases in first‐degree relatives of children with juvenile idiopathic arthritis (JIA) and to compare the figures with published population data.

Materials and methods:  Families of the 362 children with recently diagnosed JIA admitted to Rheumatism Foundation Hospital, Finland, from 1996 to 2001 were contacted by questionnaires regarding autoimmune diseases in family members. Data were collected on type 1 diabetes, coeliac disease, multiple sclerosis and chronic arthritis, consisting mainly of JIA, rheumatoid arthritis, spondyloarthropathy or psoriatic arthritis.

Results:  In all, 21.4% of the 355 families with a patient with JIA had members with type 1 diabetes, coeliac disease, multiple sclerosis or chronic arthritis. Thirty‐three mothers and 23 fathers had type 1 diabetes, coeliac disease, multiple sclerosis or chronic arthritis in 15.2% (95% CI 11.6–19.4) of the families, and 23 mothers and 15 fathers had chronic arthritis in 10.7% (95% CI 7.7–14.5) of the families. When compared with available research data, the prevalences of rheumatoid arthritis, spondyloarthropathy, psoriatic arthritis, paediatric type 1 diabetes and JIA (in siblings) were increased in JIA families. Coeliac disease was as prevalent as in the population.

Conclusion:  Autoimmune diseases cluster in families with a child with JIA.
Excessive Fall of Blood Pressure During Maintenance Hemodialysis in Patients With Chronic Renal Failure Is Induced by Vascular Malfunction and Imbalance of Autonomic Nervous Activity
Authors: Yamamoto Kazuya , Kobayashi Naoyuki , Kutsuna Toshiki , Ishii Akira , Matsumoto Takuya , Hara Miyako , Aiba Naoko , Tabata Minoru , Takahira Naonobu , Masuda Takashi
Published: March 2012

Acute hypotension during maintenance hemodialysis (HD) is not only a critical complication, but also an independent risk factor for mortality in patients with chronic renal failure (CRF). This study was designed to clarify the mechanisms underlying excessive fall of blood pressure during HD. Fifty‐six CRF patients with HD thrice a week were divided into two groups according to the intradialytic hypotension episodes after 4 weeks of the observation period; the hypotension group, showing four or more episodes of intradialytic hypotension, and the non‐hypotension group, showing three episodes of intradialytic hypotension or less. The intradialytic hypotension was defined as a fall of ≥30 mm Hg in the systolic blood pressure during HD. The brachial‐ankle pulse wave velocity (ba‐PWV), serum high‐sensitivity (hs)‐CRP, reactive oxygen species (ROS) generation, and serum malondialdehyde‐modified LDL (MDA‐LDL) were measured before HD. The high‐ frequency (HF) and low‐frequency components (LF) of the heart rate variability and entropy were analyzed by the maximal entropy method. The ba‐PWV, hs‐CRP, ROS generation, and MDA‐LDL were significantly higher in the hypotension group than in the non‐hypotension group. HF, LF/HF, and entropy during HD increased significantly in the non‐hypotension group, while entropy during HD decreased significantly in the hypotension group as compared with the baseline. LF/HF and entropy during HD were significantly lower in the hypotension group than in the non‐hypotension group. These findings suggest that the major factors causing excessive fall of blood pressure during HD in patients with CRF might be vascular malfunction and imbalance of autonomic nervous activity.
Lack of associations between ultrasonographic appearance of parenchymal lesions of the canine liver and histological diagnosis
Authors: Warren‐Smith C. M. R. , Andrew S. , Mantis P. , Lamb C. R.
Published: March 2012

Objective:To assess if there are any ultrasonographic features that may enable tentative diagnosis of hepatic parenchymal disease.

Methods:Records of 371 dogs that had abdominal ultrasonography and abnormal liver on biopsy or necropsy were reviewed.

Results:Histological diagnoses were hepatitis (n=77), nodular hyperplasia (n=47), vacuolar change (n=45), fibrosis (n=32), primary hepatic carcinoma (n=30), lymphoma (n=28), metastatic neoplasia (n=27), necrosis (n=21), lipidosis (n=17), haemangiosarcoma (n=13), round cell tumour (n=9), hepatocellular adenoma (n=8), degenerative change (n=6), steroid hepatopathy (n=7) and extramedullary haematopoiesis (n=4). The most prevalent ultrasonographic features were multifocal lesions (63% livers with haemangiosarcoma and 43% livers with hepatocellular carcinoma), diffuse lesions (71% livers with steroid hepatopathy, 44% livers with fibrosis and 40% livers with vacuolar hepatopathy), hyperechoic lesions (71% livers with steroid hepatopathy, 41% livers with lipidosis and 38% livers with fibrosis), heterogeneous lesions (62% livers with haemangiosarcoma), hepatomegaly (43% livers with steroid hepatopathy) and peritoneal fluid (62% livers with haemangiosarcoma). Target lesions were associated with malignancy in 67% instances. Marked variability in ultrasonographic appearance of lesions was observed for all diagnoses, and no statistically significant associations between ultrasonographic appearance and diagnosis were found.

ClinicalSignificance:Histological examination remains essential for diagnosis of canine hepatic disease.
Post‐trauma inguinal seroma formation in the cat
Authors: Charlesworth T. M. , Moores A. L.
Published: March 2012

Seven cats presented with large caudoventral abdominal or inguinal swellings following road traffic accidents. No case had evidence of disruption to the body wall or inguinal ring and the inguinal swellings may have been the result of either shear or compressive injury to soft tissues of the inguinum or disruption of the regional lymphatics. Six cases resolved completely following strict rest or simple Penrose drain placement with no recurrence reported. Recurrence of seroma was seen in one case but which then fully resolved following omentalisation of the inguinum.
Are Free Fatty Acids Effective Taste Stimuli in Humans?
Authors: Tucker Robin M. , Mattes Richard D.
Published: March 2012

Abstract:  The popularity of low‐ and reduced‐fat foods has increased as consumers seek to decrease their energy consumption. Fat replacers may be used in fat‐reduced products to maintain their sensory properties. However, these ingredients have been largely formulated to replicate nongustatory properties of fats to foods and have only achieved moderate success. There is increasing evidence that fats also activate the taste system and uniquely evoke responses that may influence product acceptance. Work supporting a taste component of fat has prompted questions about whether fat constitutes an additional “primary” or “basic” taste quality. This review briefly summarizes this evidence, focusing on human studies, when possible. Effective stimuli, possible receptors, and physiological changes due to oral fat exposure are discussed. Some studies suggest that there are fatty acid tasters and nontasters and if verified could have implications for targeted product development.
Rapid Discrimination and Characterization of Vanilla Bean Extracts by Attenuated Total Reflection Infrared Spectroscopy and Selected Ion Flow Tube Mass Spectrometry
Authors: Sharp Michael D. , Kocaoglu‐Vurma Nurdan A. , Langford Vaughan , Rodriguez‐Saona Luis E. , Harper W. James
Published: March 2012

Abstract:  Vanilla beans have been shown to contain over 200 compounds, which can vary in concentration depending on the region where the beans are harvested. Several compounds including vanillin, p‐hydroxybenzaldehyde, guaiacol, and anise alcohol have been found to be important for the aroma profile of vanilla. Our objective was to evaluate the performance of selected ion flow tube mass spectrometry (SIFT‐MS) and Fourier‐transform infrared (FTIR) spectroscopy for rapid discrimination and characterization of vanilla bean extracts. Vanilla extracts were obtained from different countries including Uganda, Indonesia, Papua New Guinea, Madagascar, and India. Multivariate data analysis (soft independent modeling of class analogy, SIMCA) was utilized to determine the clustering patterns between samples. Both methods provided differentiation between samples for all vanilla bean extracts. FTIR differentiated on the basis of functional groups, whereas the SIFT‐MS method provided more specific information about the chemical basis of the differentiation. SIMCA's discriminating power showed that the most important compounds responsible for the differentiation between samples by SIFT‐MS were vanillin, anise alcohol, 4‐methylguaiacol, p‐hydroxybenzaldehyde/trimethylpyrazine, p‐cresol/anisole, guaiacol, isovaleric acid, and acetic acid. ATR‐IR spectroscopy analysis showed that the classification of samples was related to major bands at 1523, 1573, 1516, 1292, 1774, 1670, 1608, and 1431 cm−1, associated with vanillin and vanillin derivatives.

Practical Application:  Fourier transform infrared attenuated total reflectance and selected ion flow tube mass spectrometry have shown to be quick and reliable methods for analyzing vanilla extracts which could be utilized as a quality assurance tool in the fragrance, flavoring, and food industries.
Mechanisms for Sensing Fat in Food in the Mouth*
Authors: Rolls Edmund T.
Published: March 2012

Abstract:  The brain areas that represent taste including the primary taste cortex and the orbitofrontal cortex also provide a representation of oral texture. Fat texture is represented by neurons independently of viscosity: some neurons respond to fat independently of viscosity, and other neurons encode viscosity. The neurons that respond to fat also respond to silicone and paraffin oil, indicating that the sensing is texture‐specific not chemo‐specific. This fat sensing is not related to free fatty acids such as linoleic acid, and a few other neurons that respond to free fatty acids typically do not respond to fat in the mouth. Complementary human functional neuroimaging studies show that the pleasantness of food texture is represented in the orbitofrontal cortex. These findings have implications for the design of foods that mimic the pleasant texture of fat in the mouth but have low energy content, and thus for the prevention and treatment of obesity.
Temporal Variation of Microbiological and Chemical Quality of Noncarbonated Bottled Drinking Water Sold in Sri Lanka
Authors: Herath A.T. , Abayasekara C.L. , Chandrajith Rohana , Adikaram N.K.B.
Published: March 2012

Abstract:  Use of bottled water in Sri Lanka has increased over the last decade, while new brands of bottled water are often introduced to the market. However, the manufacturers’ adherence to bottled water regulations is questionable, raising concerns regarding the quality of bottled water. The objective of the current study was to investigate the microbiological and chemical quality of bottled water in Sri Lanka. Thirty bottled water brands were sampled and their chemical and microbiological parameters were analyzed. Microbiological analysis was carried out within 1 to 3, 3 to 6, 6 to 9, and 9 to 12 mo after the date of manufacture. The results indicated that 63% of brands tested exceeded the levels permitted by the Sri Lanka Standards Institution (SLSI) for presumptive total coliforms (TC) (<10 cfu per 100 mL) whereas 97% brands exceeded the World Health Organization (WHO) permitted level. Thirty percent of brands exceeded the limit for presumptive fecal coliforms (FC) (0 cfu per 100 mL in accordance with WHO permitted levels, SLSI and the Sri Lanka Health Ministry requirement). Eighty percent of brands showed higher heterotrophic plate counts (HPC) which exceeded the WHO guidelines for bottled drinking water. Throughout their shelf life, the counts of TC, FC, and HPC bacteria decreased. Bacteria identified were Klebsiella pneumoniae ssp. pneumoniae, Enterobacter cloacae, Pseudomonas aeruginosa, and Pasteurella haemolytica, the most frequently being P. aeruginosa. The dominant fungi identified were Aspergillus sp. and Penicillium sp. Inorganic chemical parameters were within permitted levels for all brands except for initial content of ammonia. The results of this study show the need for the bottling industry to be monitored closely by relevant authorities, in order to provide safe bottled drinking water to consumers in Sri Lanka.
Physical and Chemical Stability of Tagatose Powder
Authors: Grant Lenese D. , Bell Leonard N.
Published: March 2012

Abstract:  Tagatose is a reduced‐calorie monosaccharide that displays prebiotic properties. Water can interact with powdered tagatose to varying extents, depending upon the storage environment. Adsorbed water can impact the stability of tagatose, altering its functionality and usability as an ingredient. The objective of this study was to evaluate the physical and chemical stability of bulk tagatose powder as a function of relative humidity (RH) and temperature. Powdered tagatose was stored in desiccators at 20, 30, and 40 °C and 33% to 85% RH. Moisture contents (MC), physical characteristics, tagatose degradation profiles, and browning kinetics were monitored for 12 mo. The critical RH associated with deliquescence (RH0) was approximately 85% at 20 °C. MC values below RH0 were all less than 2% (wb). The MC at 85% RH ranged from 55% to 80% (wb), increasing as temperature decreased. At 33% RH and 20 °C tagatose remained a free flowing powder. As either temperature or RH increased, varying degrees of physical caking occurred. At 85% RH, tagatose deliquesced at all temperatures. Browning occurred in all samples at 40 °C. Despite physical caking and browning, measurable tagatose degradation was only observed in the deliquesced sample at 85% RH and 40 °C, where 20% loss occurred in 6 mo. Although extreme RHs and temperatures are required for tagatose degradation to occur, intermediate RHs and temperatures promote physical caking and deliquescence, which create handling problems during product formulation. The exposure of tagatose to elevated relative humidities and temperatures should be avoided to maintain its physical and chemical quality.

Practical Application:  Tagatose powder is susceptible to chemical and physical deterioration during storage. To prevent undesirable changes to this healthful prebiotic ingredient, bulk tagatose powder should be stored in cool, dry environments.
Assessment of the Validity of Maturity Metrics for Predicting the Volatile Composition of Concord Grape Juice
Authors: Iyer Meera M. , Sacks Gavin L. , Padilla‐Zakour Olga I.
Published: March 2012

Abstract:  Total soluble solids (TSS) are typically used as the sole metric for maturity of Concord grapes. However, the reliability of TSS in predicting the aroma composition of finished juice for grapes sourced from multiple sites has not been investigated. This study sought to determine the validity of TSS in predicting the aroma composition of the juice while also investigating other potentially useful indicators, including pH, titratable acidity (TA), and TSS:TA ratio. Grapes were harvested from 9 sites in the Lake Erie Concord Grape Belt and stratified from north to south and east to west. The key aroma compounds methyl anthranilate (“grapey”) and trans‐2‐hexenal (“herbaceous”) were quantified along with several other odorants. It was observed that while TSS was a robust predictor of monomeric anthocyanin content across sites, it was a poor predictor of aroma compounds in the finished juice. Conversely, pH, TA, and TSS:TA ratio were all significantly correlated with methyl anthranilate and trans‐2‐hexenal concentrations (P < 0.05) in samples equal to or exceeding 15 Brix, the industry minimum for grape maturity. These results indicate that parameters related to acidity are better predictors of aroma composition than TSS, which may aid in efforts to minimize herbaceous off‐aromas and optimize the aroma composition of the finished juice.

Practical Application:  It is critical for the juice industry to have readily measurable parameters in Concord grapes upon harvesting that can predict the aroma composition of the finished juice. To date, total soluble solids (TSS) has been the industry standard for evaluating harvest maturity. Our results indicate that parameters that account for acidity (that is, titratable acidity, pH, and TSS:titratable acidity ratio) are superior in predicting the final juice aroma composition. The implementation of a more reliable predictive index at harvest can reduce the incidence of herbaceous off‐aromas in Concord grape juice, a common consumer complaint for this product.
Prevalence, clinical manifestations and endoscopic features of eosinophilic esophagitis: A pathological review in China
Authors: SHI Yi Nan , SUN Shi Jun , XIONG Li Shou , CAO Qing Hua , CUI Yi , CHEN Min Hu
Published: March 2012

OBJECTIVE:  We aimed to determine the prevalence of eosinophilic esophagitis (EoE) and define its clinical and endoscopic characteristics in Chinese patients.

METHODS:  Esophageal specimens obtained from January 2006 to December 2010 in the First Affiliated Hospital of Sun Yat‐sen University were reviewed, and the data on clinical characteristics and endoscopic findings of patients were obtained. Patients with eosinophils ≥15 per high power field (HPF) were identified as having EoE.

RESULTS:  A total of 12 patients met the criteria for EoE, establishing a prevalence of 0.34%. These patients presented with dysphagia (4/12, 33.3%), gastroesophageal reflux disease (GERD)‐like symptoms (3/12, 25.0%), abdominal pain (3/12, 25.0%) and others (2/12, 16.7%). The most common endoscopic finding was plaques (5/12, 41.7%), and other findings were irregular Z‐line (2/12, 16.7%), erosive esophagitis (2/12, 16.7%), white exudates (1/12, 8.3%), linear furrows (1/12, 8.3%), Schatzki ring (1/12, 8.3%), ulcers (1/12, 8.3%) and erythema (1/12, 8.3%).

CONCLUSIONS:  The prevalence of EoE was 0.34% in our patients. Clinicians should pay attention to patients manifested with dysphagia and GERD‐like symptomes with endosopic findings of white exudates, plaques, Schatzki ring and linear furrows.
Toward a Computational Psycholinguistics of Reference Production
Authors: van Deemter Kees , Gatt Albert , van Gompel Roger P.G. , Krahmer Emiel
Published: March 2012

This article introduces the topic ‘‘Production of Referring Expressions: Bridging the Gap between Computational and Empirical Approaches to Reference’’ of the journal Topics in Cognitive Science. We argue that computational and psycholinguistic approaches to reference production can benefit from closer interaction, and that this is likely to result in the construction of algorithms that differ markedly from the ones currently known in the computational literature. We focus particularly on determinism, the feature of existing algorithms that is perhaps most clearly at odds with psycholinguistic results, discussing how future algorithms might include non‐determinism, and how new psycholinguistic experiments could inform the development of such algorithms.
Passive Control of Noise and Instability in a Swirl-Stabilized Combustor With the Use of High-Strength Porous Insert
Authors: Sequera Daniel , Agrawal Ajay K.
Published: March 2012

Swirl-stabilized combustion and porous inert medium (PIM) combustion are two methods that have been used extensively, although independently, for flame stabilization. In this study, the two concepts are combined so that the porous insert serves as a passive device to mitigate combustion noise and instabilities. A properly shaped PIM is placed within the combustor to directly influence the turbulent flow field and vortical and/or shear layer structures associated with the outer recirculation zone and inner recirculation zone. After presenting the concept, the paper provides a conceptual understanding of the changes in the mean flow field caused by the PIM. Combustion experiments were conducted at atmospheric pressure using HfC/SiC coated open-cell foam structures of different pore sizes and shapes. Measurements of sound pressure level (SPL) and CO and NOx emissions were taken for different equivalence ratios and reactant flow rates. Combustion mode and PIM geometry to decrease the SPL are identified. The results show that the porous insert can reduce combustion noise without adversely affecting NOx and CO emissions. Experiments show that the proposed concept can also mitigate combustion instabilities encountered at high reactant flow rate.
Growth morphology and electrical/optical properties of Al-doped ZnO thin films grown by atomic layer deposition
Authors: Dhakal Tara , Vanhart Daniel , Christian Rachel , Nandur Abhishek , Sharma Anju , Westgate Charles R.
Published: March 2012

The authors report electrical and optical characterization of zinc oxide (ZnO) and Al-doped zinc oxide (AZO) films grown by atomic layer deposition (ALD). A detailed analysis of ZnO growth morphology is presented with the help of atomic force microscopy imaging, roughness analysis, and x-ray photoelectron spectroscopy surface chemistry information. Initially the film grew as islands, which coalesced to complete the substrate coverage at 50 ALD cycles. The AZO films to be used as transparent conducting oxides for solar cell applications were grown on single crystalline Si (100) and float-glass substrates at temperatures from 150–325 °C. The amount of aluminum doping was varied from 2 to 8 %. The AZO film with 5% Al exhibited the highest conductivity in the film, which increased as the growth temperature increased. Hall effect measurements of an AZO film of thickness 575 nm doped at 5% on silicon and glass substrates showed a sheet resistance (Rs) of 100 Ω/□, which improved further to 25 Ω/□ after annealing at higher temperatures in an argon-hydrogen environment. The transmittance and reflectance of the films grown on glass substrates were used to calculate the band gap. The band gap of AZO increased with Al-doping level. The transmittance of the films in the entire 0 to 8 % doping range, was found to be 80 to 90 % in the visible region. In addition, the growth rates of ZnO, Al2O3, and AZO films were also studied. The growth rate of the AZO films was 1.95 Å per ALD cycle with a cycle time of 1 s. This growth rate is relatively large for an ALD process. The interface of the AZO-Al2O3-Si(100) imaged using high resolution transmission electron microscopy showed a random texture and a continuous interface.
Housekeeping Gene Sequencing and Multilocus Variable-Number Tandem-Repeat Analysis To Identify Subpopulations within Pseudomonas syringae pv. maculicola and Pseudomonas syringae pv. tomato That Correlate with Host Specificity
Authors: Gironde S. , Manceau C.
Published: March 2012

Pseudomonas syringae
pv. maculicola causes bacterial spot on
Brassicaceae
worldwide, and for the last 10 years severe outbreaks have been reported in the Loire Valley, France.
P. syringae
pv. maculicola resembles
P. syringae
pv. tomato in that it is also pathogenic for tomato and causes the same types of symptoms. We used a collection of 106 strains of
P. syringae
to characterize the relationships between
P. syringae
pv. maculicola and related pathovars, paying special attention to
P. syringae
pv. tomato. Phylogenetic analysis of
gyrB
and
rpoD
gene sequences showed that
P. syringae
pv. maculicola, which causes diseases in
Brassicaceae
, forms six genetic lineages within genomospecies 3 of
P. syringae
strains as defined by L. Gardan et al. (Int. J. Syst. Bacteriol. 49[Pt 2]:469–478, 1999), whereas
P. syringae
pv. tomato forms two distinct genetic lineages. A multilocus variable-number tandem-repeat (VNTR) analysis (MLVA) conducted with eight minisatellite loci confirmed the genetic structure obtained with
rpoD
and
gyrB
sequence analyses. These results provide promising tools for fine-scale epidemiological studies on diseases caused by
P. syringae
pv. maculicola and
P. syringae
pv. tomato. The two pathovars had distinct host ranges; only
P. syringae
pv. maculicola strains were pathogenic for
Brassicaceae
. A subpopulation of
P. syringae
pv. maculicola strains that are pathogenic for Pto-expressing tomato plants were shown to lack
avrPto1
and
avrPtoB
or to contain a disrupted
avrPtoB
homolog. Taking phylogenetic and pathological features into account, our data suggest that the DC3000 strain belongs to
P. syringae
pv. maculicola. This study shows that
P. syringae
pv. maculicola and
P. syringae
pv. tomato appear multiclonal, as they did not diverge from a single common ancestral group within the ancestral
P. syringae
genomospecies 3, and suggests that pathovar specificity within
P. syringae
may be due to independent genetic events.
Detection of a Common and Persistent
tet
(L)-Carrying Plasmid in Chicken-Waste-Impacted Farm Soil
Authors: You Yaqi , Hilpert Markus , Ward Mandy J.
Published: March 2012

The connection between farm-generated animal waste and the dissemination of antibiotic resistance in soil microbial communities, via mobile genetic elements, remains obscure. In this study, electromagnetic induction (EMI) surveying of a broiler chicken farm assisted soil sampling from a chicken-waste-impacted site and a marginally affected site. Consistent with the EMI survey, a disparity existed between the two sites with regard to soil pH, tetracycline resistance (Tc
r
) levels among culturable soil bacteria, and the incidence and prevalence of several
tet
and
erm
genes in the soils. No significant difference was observed in these aspects between the marginally affected site and several sites in a relatively pristine regional forest. When the farm was in operation,
tet
(L),
tet
(M),
tet
(O),
erm
(A),
erm
(B), and
erm
(C) genes were detected in the waste-affected soil. Two years after all waste was removed from the farm,
tet
(L),
tet
(M),
tet
(O), and
erm
(C) genes were still detected. The abundances of
tet
(L),
tet
(O), and
erm
(B) were measured using quantitative PCR, and the copy numbers of each were normalized to eubacterial 16S rRNA gene copy numbers.
tet
(L) was the most prevalent gene, whereas
tet
(O) was the most persistent, although all declined over the 2-year period. A mobilizable plasmid carrying
tet
(L) was identified in seven of 14 Tc
r
soil isolates. The plasmid's hosts were identified as species of
Bhargavaea
,
Sporosarcina
, and
Bacillus
. The plasmid's mobilization (
mob
) gene was quantified to estimate its prevalence in the soil, and the ratio of
tet
(L) to
mob
was shown to have changed from 34:1 to 1:1 over the 2-year sampling period.
A Surface Glycoprotein Indispensable for Gamete Fusion in the Social Amoeba Dictyostelium discoideum
Authors: Araki Yoshinori , Shimizu Hideki D. , Saeki Kentaro , Okamoto Marina , Yamada Lixy , Ishida Kentaro , Sawada Hitoshi , Urushihara Hideko
Published: March 2012

Sexual reproduction is essential for the maintenance of species in a wide variety of multicellular organisms, and even unicellular organisms that normally proliferate asexually possess a sexual cycle because of its contribution to increased genetic diversity. Information concerning the molecules involved in fertilization is accumulating for many species of the metazoan, plant, and fungal lineages, and the evolutionary consideration of sexual reproduction systems is now an interesting issue. Macrocyst formation in the social amoeba
Dictyostelium discoideum
is a sexual process in which cells become sexually mature under dark and submerged conditions and fuse with complementary mating-type cells. In the present study, we isolated
D. discoideum
insertional mutants defective in sexual cell fusion and identified the relevant gene,
macA
, which encodes a highly glycosylated, 2,041-amino-acid membrane protein (MacA). Although its overall similarity is restricted to proteins of unknown function within dictyostelids, it contains LamGL and discoidin domains, which are implicated in cell adhesion. The growth and development of
macA
-null mutants were indistinguishable from those of the parental strain. The overexpression of
macA
using the V18 promoter in a
macA
-null mutant completely restored its sexual defects. Although the
macA
gene encoded exactly the same protein in a complementary mating-type strain, it was expressed at a much lower level. These results suggest that MacA is indispensable for gamete interactions in
D. discoideum
, probably via cell adhesion. There is a possibility that it is controlled in a mating-type-dependent manner.
RNA-Seq and RNA Immunoprecipitation Analyses of the Transcriptome of Streptomyces coelicolor Identify Substrates for RNase III
Authors: Gatewood Marcha L. , Bralley Patricia , Weil M. Ryan , Jones George H.
Published: March 2012

RNase III is a key enzyme in the pathways of RNA degradation and processing in bacteria and has been suggested as a global regulator of antibiotic production in
Streptomyces coelicolor
. Using RNA-Seq, we have examined the transcriptomes of
S. coelicolor
M145 and an RNase III (
rnc
)-null mutant of that strain. RNA preparations with reduced levels of structural RNAs were prepared by subtractive hybridization prior to RNA-Seq analysis. We initially identified 7,800 transcripts of known and putative protein-coding genes in M145 and the null mutant, JSE1880, along with transcripts of 21 rRNA genes and 65 tRNA genes. Approximately 3,100 of the protein-coding transcripts were categorized as low-abundance transcripts. For further analysis, we selected those transcripts of known and putative protein-coding genes whose levels changed by ≥2-fold between the two
S. coelicolor
strains and organized those transcripts into 16 functional categories. We refined our analysis by performing RNA immunoprecipitation of the mRNA preparation from JSE1880 using a mutant RNase III protein that binds to transcripts but does not cleave them. This analysis identified ca. 800 transcripts that were enriched in the RNA immunoprecipitates, including 28 transcripts whose levels also changed by ≥2-fold in the RNA-Seq analysis. We compare our results with those obtained by microarray analysis of the
S. coelicolor
transcriptome and with studies describing the characterization of small noncoding RNAs. We have also used the RNA immunoprecipitation results to identify new substrates for RNase III cleavage.
Association of National Hospital Quality Measure adherence with long-term mortality and readmissions
Authors: Shahian David M , Meyer Gregg S , Mort Elizabeth , Atamian Susan , Liu Xiu , Karson Andrew S , Ramunno Lawrence D , Zheng Hui
Published: March 2012

Background

In existing studies, the association between adherence with recommended hospital care processes and subsequent outcomes has been inconsistent. This has substantial implications because process measure scores are used for accountability, quality improvement and reimbursement. Our investigation addresses methodological concerns with previous studies to better clarify the process–outcomes association for three common conditions.

Methods

The study included all patients discharged from Massachusetts General Hospital between 1 July 2004 and 31 December 2007 with a principle diagnosis of acute myocardial infarction (AMI), heart failure (HF) or pneumonia (PN) who were eligible for at least one National Hospital Quality Measure. The number of patients analysed varied by measure (374 to 3020) depending on Centers for Medicare and Medicaid Services eligibility criteria. Hospital data were linked with state administrative data to determine mortality and readmissions. For patients with multiple admissions, the time-weighted impact of measure failures on mortality was estimated using exponential decay functions. All patients had follow-up for at least 1 year or until death or readmission. Cox models were used to estimate HRs adjusted for transfer status, age, gender, race, census block-group socioeconomic status, number of Elixhauser comorbidities, and do not resuscitate orders.

Results

Adjusted survival and freedom from readmission for AMI and PN showed superior results for 100% and 50–99% adherence compared with 0–49% adherence. For HF, the results were inconsistent and sometimes paradoxical, although several individual measures (eg, ACE inhibitor/angiotensin receptor blockade) were associated with improved outcomes.

Conclusion

Adherence with recommended AMI and PN care processes is associated with improved long-term outcomes, whereas the results for HF measures are inconsistent. The evidence base for all process measures must be critically evaluated, including the strength of association between these care processes and outcomes in real-world populations. Some currently recommended processes may not be suitable as accountability measures.
Evaluating acute medical admissions through emergency departments in Hong Kong: can one adjust for case-mix variation?
Authors: Rainer T H , Sollich P , Piotrowski T , Coolen A C C , Cheng B , Graham C A
Published: March 2012

Background

Healthcare systems are under pressure to efficiently and safely reduce acute care admissions to hospital. There is a need to develop a standardised system for assessing emergency department performance which takes into account case-mix variation. The objective of this study was to derive and validate a standardised tool for assessing variations in medical admissions through emergency departments in Hong Kong.

Methods

Retrospective study of patients attending emergency departments of 14 acute hospitals in Hong Kong. Data were retrieved from a centralised administrative database.

Results

Of 2 531 225 patients who attended emergency departments between 1 January 2001 and 31 December 2003, 780 444 (30.8%) were admitted to medical wards. A model derived from 2001 data shows well-calibrated admission probabilities, with an area under the receiver operating characteristic curve for probability of admission of 90.3 (95% CI ±0.11). The areas under the receiver operating characteristic curves for 2002 and 2003 validation sets were 89.9 (95% CI ±0.11) and 89.0 (95% CI ±0.12), respectively. With an averaged benchmark, reductions in medical admissions of up to 19% could be achieved, while under the most optimistic assumption, reductions of up 36% could be achieved.

Conclusions

A tool for benchmarking hospital medical admissions and minimising case-mix variation has been derived and validated in Hong Kong, but it requires further validation in other healthcare systems given the wide variations in admission thresholds internationally. This may be used as one potential method to evaluate the performance of emergency departments against a common standard.
The enduring effects of marital status on subsequent depressive symptoms among women: investigating the roles of psychological, social and financial resources
Authors: LaPierre Tracey A
Published: March 2012

Objectives

To investigate the mechanisms through which marital status exerts long-term effects on depressive symptoms among women and to evaluate the relative importance of psychological, social and financial resources in mediating this relationship.

Methods

Data came from 6107 female respondents to a nationally representative longitudinal data set from the USA (National Survey of Families and Households 1987–1988/1992–1994). Mediation was investigated using semi-longitudinal structural equation modelling and bias-corrected bootstrapped CIs. Latent constructs with multiple indicators were used to measure depressive symptoms, primary and secondary social integration and self-esteem.

Results

The total effect of marital status on subsequent depressive symptoms was statistically significant for all marital statuses relative to those in first marriages controlling for age, education, race, number of children younger than 5 in the household, T1 depressive symptoms and marital status transitions between waves; all groups experienced higher levels of depressive symptoms than those in first marriages. These effects were completely mediated for never-married women and partially mediated for separated/divorced, widowed and cohabiting women. Adjusted household income was the largest mediator for the separated/divorced, widowed and never-married, but primary social integration also played a role. Self-esteem was the only significant mediator for the remarried and cohabiting and was also important in explaining differences between the first-married and separated/divorced.

Conclusion

This study demonstrates that the reasons why marital status has an influence on subsequent depressive symptoms varies depending on the specific marital status being compared with the married.
Cerebral aneurysm wall thickness analysis using intraoperative microscopy: effect of size and gender on thin translucent regions
Authors: Kadasi Laith M , Dent Walter C , Malek Adel M
Published: March 2012

Objective

Wall thickness is a poorly documented characteristic of cerebral aneurysms which may provide insight into adaptive aneurysmal growth, aneurysm rupture risk and response to endovascular treatment. The distribution of aneurysm wall thickness, as observed by intraoperative video microscopy, is described.

Methods

54 unruptured saccular cerebral aneurysms were selected based on the availability of intraoperative video obtained from patients undergoing microsurgical clipping. Aneurysms were assessed for the distribution of wall thickness based on color translucence and quantitation of pixel values at superthin translucent, intermediate and thick regions of the dome. The data were analyzed with respect to aneurysm morphology, location and associated demographic factors.

Results

The mean proportions of tissue characteristic among all domes analyzed were found to be 27% superthin, 65% intermediate, and 8% thick. Smaller aneurysms having a maximal dimension Dmax<7 mm had a higher proportion of superthin tissue (p=0.003) and lower thick tissue (p=0.001) content. Female gender was associated with a significantly higher proportion of superthin tissue at the aneurysm dome (p=0.038), with no statistical dependence seen with patient age, smoking status or anatomical location.

Conclusion

The dome of unruptured aneurysms is a highly heterogeneous region with areas of variable thickness that appear to be intimately related to the process of aneurysm development. This inconstant property affects wall tensile stress, may play a role in aneurysm pathogenesis and focal rupture, and should be incorporated into future analyses of aneurysm rupture risk and mechanics.
RELIC DENSITY AND PAMELA EVENTS IN A HEAVY WINO DARK MATTER MODEL WITH SOMMERFELD EFFECT
Authors: MOHANTY SUBHENDRA , RAO SOUMYA , ROY D. P.
Published: March 2012

In a wino LSP scenario the annihilation cross-section of winos gravitationally bound in galaxies can be boosted by a Sommerfeld enhancement factor which arises due to the ladder of exchanged W bosons between the initial states. The boost factor obtained can be in the range S ≃104 if the mass is close to the resonance value of M ≃4 TeV . In this paper we show that if one takes into account the Sommerfeld enhancement in the relic abundance calculation then the correct relic density is obtained for 4 TeV wino mass due to the enhanced annihilation after their kinetic decoupling. At the same time the Sommerfeld enhancement in the χχ→W+ W- annihilation channel is sufficient to explain the positron flux seen in PAMELA data without significantly exceeding the observed antiproton signal. We also show that (e-+e+) and γ-ray signals are broadly compatible with the Fermi-LAT observations. In conclusion we show that a 4 TeV wino DM can explain the positron and antiproton fluxes observed by PAMELA and at the same time give a thermal relic abundance of CDM consistent with WMAP observations.
POSITIVITY FOR REGULAR CLUSTER CHARACTERS IN ACYCLIC CLUSTER ALGEBRAS
Authors: DUPONT G.
Published: March 2012

Let Q be an acyclic quiver and let [Formula: see text] be the corresponding cluster algebra. Let H be the path algebra of Q over an algebraically closed field and let M be an indecomposable regular H-module. We prove the positivity of the cluster characters associated to M expressed in the initial seed of [Formula: see text] when either H is tame and M is any regular H-module, or H is wild and M is a regular Schur module which is not quasi-simple.
A MULTI-GROUP SVEIR EPIDEMIC MODEL WITH DISTRIBUTED DELAY AND VACCINATION
Authors: WANG JINLIANG , TAKEUCHI YASUHIRO , LIU SHENGQIANG
Published: March 2012

In this paper, based on a class of multi-group epidemic models of SEIR type with bilinear incidences, we introduce a vaccination compartment, leading to multi-group SVEIR model. We establish that the global dynamics are completely determined by the basic reproduction number [Formula: see text] which is defined by the spectral radius of the next generation matrix. Our proofs of global stability of the equilibria utilize a graph-theoretical approach to the method of Lyapunov functionals. Mathematical results suggest that vaccination is helpful for disease control by decreasing the basic reproduction number. However, there is a necessary condition for successful elimination of disease. If the time for the vaccines to obtain immunity or the possibility for them to be infected before acquiring immunity is neglected in each group, this condition will be satisfied and the disease can always be eradicated by suitable vaccination strategies. This may lead to over evaluation for the effect of vaccination.