bluuebunny/crossref_metadata_2025 huggingface dataset:
Dentigerous cyst associated with an impacted anterior maxillary supernumerary tooth
Authors: Shah Kaushal Mahendra , Karagir Amol , Adaki Shridevi , Pattanshetti Channaveer
Published: February 2013

Most typical dentigerous cysts are commonly seen in association with third molars and maxillary canines. Only 5–6% of dentigerous cysts are associated with supernumerary teeth. We report a rare case of dentigerous cyst associated with an impacted anterior maxillary supernumerary tooth. The patient was treated surgically by enucleation of the cyst.
Portal biliary ductopathy caused by cavernous transformation of the portal vein
Authors: Chong Jeffrey Chu-Nan , Boyapati Ray , Rusli Ferry
Published: February 2013

A 42-year-old woman presented with a 1-week history of epigastric pain and deranged liver function tests (LFTs) on a background of known portal vein thrombosis (PVT) with cavernous transformation. Imaging with ultrasound, CT and MR cholangiopancreatography demonstrated known PVT, with distortion of the common bile duct and a bulky head/proximal body of the pancreas, thought to be due to mass effect from cavernous transformation related to PVT. At endoscopic retrograde cholangiopancreatography, the common hepatic duct was noted to be smaller in diameter, without any filling defects or discrete strictures. Sphincterotomy and balloon trawl was performed, with subsequent improvement of the woman's LFTs and abdominal pain.
Pulmonary hypertension in a patient with hereditary haemorrhagic telangiectasia
Authors: Chadha Davinder , Handa Ajay , Kumar Abhishek
Published: February 2013

A young male patient reported for evaluation of progressive easy fatigability, accompanied by a recent history of recurrent haemoptysis. His clinical examination was unremarkable except for evidence of pulmonary arterial hypertension (PAH). Routine investigations (haemogram, coagulogram, serological tests for connective tissue disorders and a sputum Ziehl Neelsen stain for acid-fast bacilli) were normal. Two-dimensional echocardiography suggested PAH (pulmonary artery systolic pressure—67 mm Hg), whereas the 64-slice spiral CT pulmonary angiogram showed a dilated main pulmonary artery along with bilateral arteriovenous malformations. Cardiac catheterisation performed subsequently confirmed the presence of PAH. On the basis of the above findings, a diagnosis of hereditary haemorrhagic telangiectasia (HHT) complicated with PAH was made, and the patient was started on oral sildenafil therapy to which he responded well. This rare complication of HHT, which requires a high degree of suspicion for diagnosis, is discussed.
Acute gastric incarceration from thoracic herniation in pregnancy following laparoscopic antireflux surgery
Authors: Brygger Louise , Fristrup Claus Wilki , Harbo Frederik Severin Gråe , Jørgensen Jan Stener
Published: February 2013

Diaphragmatic hernia is a rare complication in pregnancy which due to misdiagnosis or management delays may be life-threatening. We report a case of a woman in the third trimester of pregnancy who presented with sudden onset of severe epigastric and thoracic pain radiating to the back. Earlier in the index pregnancy, she had undergone laparoscopic antireflux surgery (ARS) for a hiatus hernia because of severe gastro-oesophageal reflux. Owing to increasing epigastric pain a CT scan was carried out which diagnosed wrap disruption with gastric herniation into the thoracic cavity and threatened incarceration. This is, to our knowledge, the first report of severe adverse outcome after ARS during pregnancy, with acute intrathoracic gastric herniation. We recommend the avoidance of ARS in pregnancy, and the need to advise women undergoing ARS of the postoperative risks if pregnancy occurs within a few years of ARS.
Scuba diving, acute left anterior descending artery occlusion and normal ECG
Authors: Doll Sébastien Xavier , Rigamonti Fabio , Roffi Marco , Noble Stéphane
Published: February 2013

We report the case of an acute proximal occlusion of the left anterior descending coronary (LAD) artery following a scuba diving decompression accident and associated with normal ECG. Following uneventful thromboaspiration and coronary stenting, the patient was discharged on day  4 with secondary preventative therapies. A transthoracic echocardiography performed at this point showed a complete recovery compared with an initial localised akinesia involving the anterior and apical portion of the left ventricle upon admission. This case highlights that significant acute coronary lesions involving the LAD can occur without any ECG anomaly. The presence of acute and persistent angina associated with troponin elevation should prompt physicians to consider coronary angiography without delay, independently of the ECG results.
Cardiac adaptation to exercise in adolescent athletes of African ethnicity: an emergent elite athletic population
Authors: Sheikh Nabeel , Papadakis Michael , Carre Francois , Kervio Gaelle , Panoulas Vasilis F , Ghani Saqib , Zaidi Abbas , Gati Sabiha , Rawlins John , Wilson Mathew G , Sharma Sanjay
Published: February 2013

Background/aims

Adult black athletes (BA) exhibit left ventricular hypertrophy (LVH) on echocardiography and marked ECG repolarisation changes resembling those observed in hypertrophic cardiomyopathy (HCM). Limited data are available for adolescent BA, the group most vulnerable to exercise-related sudden cardiac death.

Methods

Between 1996 and 2011, 245 male and 84 female adolescent BA from a wide variety of sporting disciplines underwent cardiac evaluation including ECG and echocardiography. Athletes exhibiting T-wave inversions and/or echocardiographic LVH were investigated further for quiescent cardiomyopathies. Results were compared with 903 adolescent white athletes (WA) and 134 adolescent sedentary black controls (BC).

Results

LVH on echocardiography was present in 7% of BA compared to only 0.6% of WA and none of the BC. In the very young (<16 years), 5.5% of BA, but none of the WA, demonstrated LVH. Within the BA group, LVH was more prevalent in men compared to women (9% vs 1.2%, p=0.012). T-wave inversions were present in 22.8% BA, 4.5% WA and 13.4% BC. T-wave inversions in BA occurred with similar frequency in men and women and were predominantly confined to leads V1–V4. T-wave inversions in the lateral leads, commonly associated with cardiomyopathies, were present in 2.4% of BA. On a further evaluation and mean follow-up of 8.3 years, none of the athletes exhibited HCM.

Conclusions

Athletic training has a pronounced effect on adolescent BA. Black athletes as young as 14 years of age may exhibit left ventricular wall thicknesses of 15 mm and marked repolarisation changes resembling HCM. Male and female BA demonstrate a high prevalence of T-wave inversions.
A new stratified risk assessment tool for whiplash injuries developed from a prospective observational study
Authors: Kasch Helge , Kongsted Alice , Qerama Erisela , Bach Flemming W , Bendix Tom , Jensen Troels Staehelin
Published: February 2013

Objectives

An initial stratification of acute whiplash patients into seven risk-strata in relation to 1-year work disability as primary outcome is presented.

Design

The design was an observational prospective study of risk factors embedded in a randomised controlled study.

Setting

Acute whiplash patients from units, general practitioners in four Danish counties were referred to two research centres.

Participants

During a 2-year inclusion period, acute consecutive whiplash-injured (age 18–70 years, rear-end or frontal-end car accident and WAD (whiplash-associated disorders) grades I–III, symptoms within 72 h, examination prior to 10 days postinjury, capable of written/spoken Danish, without other injuries/fractures, pre-existing significant somatic/psychiatric disorder, drug/alcohol abuse and previous significant pain/headache). 688 (438 women and 250 men) participants were interviewed and examined by a study nurse after 5 days; 605 were completed after 1 year. A risk score which included items of initial neck pain/headache intensity, a number of non-painful complaints and active neck mobility was applied. The primary outcome parameter was 1-year work disability.

Results

The risk score and number of sick-listing days were related (Kruskal-Wallis, p<0.0001). In stratum 1, less than 4%, but in stratum 7, 68% were work-disabled after 1 year. Early work assessment (p<0.0001), impact of the event questionnaire (p<0.0006), psychophysical pain measures being McGill pain questionnaire parameters (p<0.0001), pressure pain algometry (p<0.0001) and palpation (p<0.0001) showed a significant relationship with risk stratification.

Analysis

Findings confirm previous studies reporting intense neck pain/headache and distress as predictors for work disability after whiplash. Neck-mobility was a strong predictor in this study; however, it was a more inconsistent predictor in other studies.

Conclusions

Application of the risk assessment score and use of the risk strata system may be beneficial in future studies and may be considered as a valuable tool to assess return-to-work following injuries; however, further studies are needed.
Oral bisphosphonates are associated with increased risk of subtrochanteric and diaphyseal fractures in elderly women: a nested case–control study
Authors: Erviti Juan , Alonso Álvaro , Oliva Belén , Gorricho Javier , López Antonio , Timoner Julia , Huerta Consuelo , Gil Miguel , De Abajo Francisco
Published: February 2013

Objectives

To evaluate the association between bisphosphonate use and the risk of atypical femoral fractures among women aged 65 or older.

Design

Nested case–control study.

Setting

General practice research database in Spain.

Exposures

Use of oral bisphosphonates before the occurrence of atypical fractures among cases or the corresponding index date among controls. Bisphosphonate use was categorised as ever versus never users. Ever users were divided according to the total time since first prescription.

Main outcome measures

Cases were defined as women aged 65 years or older with a first diagnosis of subtrochanteric or diaphyseal fracture, recorded in the BIFAP database between 1 January 2005 and 31 December 2008, and with at least 1 year of follow-up before the index date. For each case, five age-matched and calendar-year-matched controls without a history of hip or atypical fracture were randomly selected from the database.

Statistical analysis

OR of atypical femoral fracture by bisphosphonate use was determined using conditional logistic regression. Models were adjusted for comorbidities and use of other medications.

Results

The analysis included 44 cases and 220 matched controls (mean age, 82 years). Ever use of bisphosphonates was more frequent in cases than controls (29.6% vs 10.5%). In multivariate analyses, OR (95% CI) of atypical femoral fracture was 4.30 (1.55 to 11.9) in ever versus never users of bisphosphonates. The risk increased with long-term use, with an OR of 9.46 (2.17 to 41.3) comparing those using bisphosphonates over 3 years versus no users (p for trend=0.01).

Conclusions

Bisphosphonate use was associated with an increased risk of subtrochanteric or diaphyseal fractures in elderly women in a low fracture risk population, with a higher risk among long-term bisphosphonate users.
Measuring relational aspects of hospital care in England with the ‘Patient Evaluation of Emotional Care during Hospitalisation’ (PEECH) survey questionnaire
Authors: Murrells Trevor , Robert Glenn , Adams Mary , Morrow Elizabeth , Maben Jill
Published: February 2013

Objectives

To first, validate in English hospitals the internal structure of the ‘Patient Evaluation of Emotional Care during Hospitalisation’ (PEECH) survey tool which was developed in Australia and, second, to examine how it may deepen the understanding of patient experience through comparison with results from the Picker Patient Experience Questionnaire (PPE-15).

Design

A 48-item survey questionnaire comprising both PEECH and PPE-15 was fielded. We performed exploratory factor analysis and then confirmatory factor analysis using a number of established fit indices. The external validity of the PEECH factor scores was compared across four participating services and at the patient level, factor scores were correlated with the PPE-15.

Setting

Four hospital services (an Emergency Admissions Unit; a maternity service; a Medicine for the Elderly department and a Haemato-oncology service) that contrasted in terms of the reported patient experience performance.

Participants

Selection of these acute service settings was based on achieving variation of the following factors: teaching hospital/district general hospital, urban/rural locality and high-performing/low-performing organisations (using results of annual national staff and patient surveys). A total of 423 surveys were completed by patients (26% response rate).

Results

A different internal structure to the PEECH instrument emerged in English hospitals. However, both the existing and new factor models were similar in terms of fit. The correlations between the new PEECH factors and the PPE-15 were all in the expected direction, but two of the new factors (personal interactions and feeling valued) were more strongly associated with the PPE-15 than the remaining two factors (feeling informed and treated as an individual).

Conclusions

PEECH can help to build an understanding of complex interpersonal aspects of quality of care, alongside the more transactional and functional aspects typically captured by PPE-15. Further testing of the combined instrument should be undertaken in a wider range of healthcare settings.
The utility of copeptin in the emergency department as a predictor of adverse outcomes in non-ST-elevation acute coronary syndrome: the COPED-PAO study
Authors: Sánchez Miquel , Llorens Pere , Herrero Pablo , Martín-Sanchez F Javier , Piñera Pascual , Miró Òscar ,   on behalf of COPEP study investigators
Published: February 2013

Aims

To test the utility of a single copeptin determination at presentation to the emergency department (ED) as a short-term prognosis marker in patients with non-ST-elevation acute coronary syndrome (NSTEACS). To compare the results with those achieved with conventional troponin.

Methods

A multicentric, prospective, observational, longitudinal, cohort study involving 15 Spanish EDs. Inclusion: consecutive patients with chest pain (<12 h) finally diagnosed of NSTEACS. Measurements: copeptin and troponin at arrival. Cut-off point for copeptin: 25.9 pmol/l. Follow-up: within 2 months after ED attendance to identify 30-day adverse events. Discriminatory capacity of copeptin and troponin was compared by receiver operating characteristic (ROC) curves.

Results

We included 377 patients with NSTEACS. Adverse events: 11 (2.9%) patients died, 27 (7.2%) had an adverse coronary event, 14 (3.7%) had a stroke, and 48 (12.7%) a composite endpoint. The initial copeptine value was over 25.9 pmol/l in 114 patients, and they presented a higher mortality rate (OR: 4.2, (95% CI 1.2 to 14.8); p=0.03). This association disappeared after adjusting by clinical variables or troponin level. No significant differences were found for the remaining endpoints. The area under the curve  of the ROC curve of 30-day mortality was 0.73 (95% CI 0.58 to 0.87) for copeptin, and 0.80 (95% CI 0.73 to 0.87) for troponin.

Conclusions

In patients with NSTEACS, determination of copeptin at presentation to the ED is associated with risk of death during the subsequent month. This association, however, disappears after adjusting by baseline features or troponin level, so copeptin does not add complementary prognostic information over that provided by troponin.
Should we customise critical value procedure according to patient origin and laboratory turnaround time?
Authors: Salinas Maria , López-Garrigós Maite , Gutiérrez Mercedes , Lugo Javier , Flors Lucia , Leiva-Salinas Carlos
Published: February 2013

Introduction

Our routine laboratory critical value notification procedure is based on a short list of six fundamental critical values. The report system for our Stat laboratory is not based on this ‘short list’; instead, critical values are always reported according to the patient clinical context and the previous laboratory results. The aim of our work is to show how a critical value notification procedure based on a rigid list of values and thresholds can result in completely different results depending on whether the tests are requested in a stat or a routine manner.

Material and methods

We reviewed the number of critical value notifications based on the short list for the routine laboratory. For the stat laboratory, we studied the number of real notifications based on the pathologist validation of the individualised situation of the patient and calculated the number of notifications that would have been reported if the routine short list would have been used instead.

Results

The number of critical values that would have been reported if using the routine short list in stat laboratory was high when compared with the number of critical values that were really reported.

Conclusions

Using a rigid list of laboratory values to notify critical values resulted in completely different results depending on whether the tests were requested in stat or routine. Reporting only really unexpected values through an individual custom-made reporting procedure may avoid the wasting of time and resources and raising false alarms among referring physicians and patients.
Molecular alterations in metaplastic breast carcinoma
Authors: Cooper Caroline Louise , Karim Rooshdiya Z , Selinger Christina , Carmalt Hugh , Lee C Soon , O'Toole Sandra A
Published: February 2013

Metaplastic carcinoma of the breast is a rare and heterogeneous subtype of breast carcinoma with a generally poor outcome, and few therapeutic options once disease recurs or progresses. Metaplastic carcinomas of the breast are usually of a larger size at diagnosis, with less frequent nodal metastasis compared with invasive ductal carcinoma no special type, and lack hormone and HER2 receptor expression. Recent research has revealed some potentially actionable genetic changes in a subset of these rare tumours. However, ongoing efforts to further characterise the genetic basis and the molecular alterations underlying the distinctive morphological and clinical characteristics of these tumours are needed in order to identify new targets for treatment. This review will describe the theories of pathogenesis of metaplastic breast carcinoma, and highlight genetic changes and potential therapeutic targets in this generally poor prognosis malignancy.
Extreme hyperferritinaemia; clinical causes
Authors: Crook Martin A , Walker Patrick L C
Published: February 2013

There are many causes of raised serum ferritin concentrations including iron overload, inflammation and liver disease to name but a few examples. Cases of extreme hyperferritinaemia (serum ferritin concentration equal to or greater than 10 000 ug/l) are being reported in laboratories but the causes of this are unclear. We conducted an audit study to explore this further. Extreme hyperferritinaemia was rare with only 0.08% of ferritin requests displaying this. The main causes of extreme hyperferritinaemia included multiple blood transfusions, malignant disease, hepatic disease and suspected Still's disease.
Recruitment limitation, germination of dust seeds, and early development of underground seedlings in six Pyroleae species
Authors: Johansson Veronika A. , Eriksson Ove
Published: February 2013

We investigated recruitment of six mixotrophic Pyroleae species in relation to soil and adult presence. Pyroleae have dust seeds containing minimal nutrient reserves, and subterranean seedlings are mycoheterotrophic needing fungal hosts for germination and development. Germination and seedling development were studied by retrieving seed bags that had been placed within plots with adults present and at unoccupied control plots. There are two main alternatives to what limits recruitment of plants, seed limitation or microsite limitation. Results suggested that a combination of microsite and seed limitation was important for all investigated species. Microsite availability was the main limiting factor for Chimaphila umbellata (L.) W.P.C. Barton, Orthilia secunda (L.) House, and Pyrola chlorantha Sw., whereas seed availability was the main limiting factor for Pyrola minor L. For Moneses uniflora L. A. Gray and Pyrola rotundifolia L., it was not clear whether microsite or seed limitation dominated. Growth of seedlings responded positively to adult presence (O. secunda and P. minor), whereas others were negatively affected (M. uniflora and P. chlorantha). Increased levels of soil nutrients (N and P) had a negative effect on seedling growth in C. umbellata and P. chlorantha. These results provide the first evidence of the importance of microsite and seed limitation for germination and development of seedlings of Pyroleae species.
Genetic relationships between wood quality traits and diameter growth of juvenile core wood in Sitka spruce
Authors: Kennedy S.G. , Cameron A.D. , Lee S.J.
Published: February 2013

The trend towards shorter rotations in planted conifer stands has resulted in a reduction in the proportion of mature wood relative to juvenile core wood, raising concerns that the mechanical performance of sawn battens will be affected. The potential to improve the wood quality of the juvenile core of Sitka spruce (Picea sitchensis (Bong.) Carrière) without compromising growth rate was investigated. Rapid and inexpensive indirect methods of assessing wood properties on standing trees using a Pilodyn gun and acoustic velocity were compared with direct measurements made on wood samples cut from the juvenile core. Strong genetic correlations were observed between Pilodyn gun values and direct measures of density (–0.76) and between the square of acoustic velocity and modulus of elasticity (0.73). The genetic correlation between the square of acoustic velocity and microfibril angle was also strong (–0.84). These results suggest that indirect assessments of wood properties within juvenile core wood are sufficiently reliable for these techniques to be used in the Sitka spruce breeding programme. Although a strong negative genetic correlation between diameter at breast height and density was noted (–0.79), sufficient variation exists within the breeding population to select families with both good growth rate and high modulus of elasticity wood.
Plant phenological modeling and its application in global climate change research: overview and future challenges
Authors: Zhao Meifang , Peng Changhui , Xiang Wenhua , Deng Xiangwen , Tian Dalun , Zhou Xiaolu , Yu Guirui , He Honglin , Zhao Zhonghui
Published: February 2013

Plants interact to the seasonality of their environments, and changes in plant phenology have long been regarded as sensitive indicators of climatic change. Plant phenology modeling has been shown to be the simplest and most useful tool to assess phenol–climate shifts. Temperature, solar radiation, and water availability are assumed to be the key factors that control plant phenology. Statistical, mechanistic, and theoretical approaches have often been used for the parameterization of plant phenology models. The statistical approaches correlate the timing of phenological events to environmental factors or heat unit accumulations. The approaches have the simplified calculation procedures, correct phenological mechanism assumptions, but limited applications and predictive abilities. The mechanistic approaches describe plant phenology with the known or assumed “cause–effect relationships” between biological processes and key driving variables. The mechanistic approaches have the improved parameter processes, realistic assumptions, broad applications, and effective predictions. The theoretical approaches assume cost–benefit tradeoff strategies in trees. These methods are capable of capturing and quantifying the potential impacts and consequences of global climate change and human activity. However, certain limitations still exist related to our understanding of phenological mechanisms in relation to (1) interactions between plants and their specific climates, (2) the integration of both field observational and remote sensing data with plant phenology models across taxa and ecosystem type, (3) amplitude clarification of scale-related sensitivity to global climate change, and (4) improvements in parameterization processes and the overall reduction of modeling uncertainties to forecast impacts of future climate change on plant phenological dynamics. To improve our capacity in the prediction of the amplitude of plant phenological responses with regard to both structural and functional sensitivity to future global climate change, it is important to refine modeling methodologies by applying long-term and large-scale observational data. It is equally important to consider other less used but critical factors (such as heredity, pests, and anthropogenic drivers), apply advanced model parameterization and data assimilation techniques, incorporate process-based plant phenology models as a dynamic component into global vegetation dynamic models, and test plant phenology models against long-term ground observations and high-resolution satellite data across different spatial and temporal scales.
ON FINITE BRANCHED UNIFORMIZATIONS OF THE PROJECTIVE PLANE
Authors: ULUDAĞ A. MUHAMMED , SARIOĞLU CELAL CEM
Published: February 2013

We give a brief survey of the so-called Fenchel's problem for the projective plane, that is the problem of existence of finite Galois coverings of the complex projective plane branched along a given divisor and prove the following result: Let p, q be two integers greater than 1 and C be an irreducible plane curve. If there is a surjection of the fundamental group of the complement of C into a free product of cyclic groups of orders p and q, then there is a finite Galois covering of the projective plane branched along C with any given branching index.
IRIS RECOGNITION USING COMBINED STATISTICAL AND CO-OCCURRENCE MULTI-RESOLUTIONAL FEATURES
Authors: RAJA SEKAR J. , ARIVAZHAGAN S. , PRIYADHARSHINI S. SHOBANA , SHUNMUGAPRIYA S.
Published: February 2013

Iris recognition is one of the most reliable personal identification methods. This paper presents a novel algorithm for iris recognition encompassing iris segmentation, fusion of statistical and co-occurrence features extracted from the curvelet and ridgelet transformed images. In this work, the pupil and iris boundaries are detected by using the equation of circle from three points on its circumference. Using Canny edge detection, the iris radius value is empirically chosen based on rigorous experimentation. Eyelash removal is done by using a horizontal 1-D rank filter. Iris normalization is done by mapping the detected iris region from the polar domain to the rectangular domain and the multi-resolution transforms such as curvelet and ridgelet transforms are applied for multi-resolutional feature extraction. The classification is done using Manhattan distance (Md) and multiclass classifier with logistic function and the two results are compared. Here, the benchmark database CASIA-IRIS-V3 (Interval) is used for identification and recognition. It is observed that the ridgelet transform increases the iris recognition rate.
HOMFLY-PT SKEIN MODULE OF SINGULAR LINKS IN THE THREE-SPHERE
Authors: PARIS LUIS , WAGNER EMMANUEL
Published: February 2013

For a ring R, we denote by [Formula: see text] the free R-module spanned by the isotopy classes of singular links in 𝕊3. Given two invertible elements x, t ∈ R, the HOMFLY-PT skein module of singular links in 𝕊3(relative to the triple (R, t, x)) is the quotient of [Formula: see text] by local relations, called skein relations, that involve t and x. We compute the HOMFLY-PT skein module of singular links for any R such that (t-1- t + x) and (t-1- t - x) are invertible. In particular, we deduce the Conway skein module of singular links.
ITERATED POWER INTERSECTIONS OF IDEALS IN RINGS OF ITERATED DIFFERENTIAL POLYNOMIALS
Authors: PŘÍHODA PAVEL , PUNINSKI GENA
Published: February 2013

Let R be an n-iterated ring of differential polynomials over a commutative noetherian domain which is a ℚ-algebra. We will prove that for every proper ideal I of R, the (n + 1)-iterated intersection I(n + 1) of powers of I equals zero. A standard application includes the freeness of non-finitely generated projective modules over such rings. If I is a proper ideal of the universal enveloping algebra of a finite-dimensional solvable Lie algebra over a field of characteristic zero, then we will improve the above estimate by showing that I(2) = 0.
SEMIPRIME LEFT QUASI-MORPHIC RINGS
Authors: NICHOLSON W. K.
Published: February 2013

A ring R is called left quasi-morphic if {Ra ∣ a ∈ R} = {l(b)∣ b ∈ R} where l(b) denotes the left annihilator of b. In 2007 Camillo and Nicholson showed that if R is quasi-morphic (left and right) and satisfies the ACC on {Ra ∣ a ∈ R}, then R is an artinian principal ideal ring. This is a new characterization of these rings. In this paper we use results of Goldie to obtain an analogue of this theorem for semiprime left quasi-morphic rings with ACC on {Ra ∣ a ∈ R}.
ON THE SUM OF ELEMENT ORDERS OF FINITE SIMPLE GROUPS
Authors: MAREFAT YADOLLAH , IRANMANESH ALI , TEHRANIAN ABOLFAZL
Published: February 2013

Let G be a finite group and ψ(G) = ∑g∈Go(g), where o(g) denotes the order of g ∈ G. In this short paper we show that the conjecture of minimality of ψ(G) in simple groups, posed in [J. Algebra Appl. 10(2) (2011) 187–190], is incorrect.
ON STRONGLY C2 MODULES AND D2 MODULES
Authors: LI WENXI , CHEN JIANLONG , KOURKI FARID
Published: February 2013

Let R be a ring, MR be a right R-module, n be a positive integer and S = End (MR) be the endomorphism ring of MR. MR is called a strongly C2 module if [Formula: see text] is C2 for every positive integer m. MR is called an n-C2 module if the annihilator rM(K) ≠ 0 for any n-generated proper left ideal K of S. We prove that MR is strongly C2 if and only if M is n-C2 for every positive integer n, if and only if the annihilator rM(K) is not zero for every finitely generated proper left ideal K of S, and then we get some characterizations of right n-C2 rings and strongly right C2 rings. Also we obtain some dual statements of n-D2 module and strongly D2 module.
APPLYING BUCHBERGER'S CRITERIA FOR COMPUTING GRÖBNER BASES OVER FINITE-CHAIN RINGS
Authors: HASHEMI AMIR , ALVANDI PARISA
Published: February 2013

Norton and Sălăgean [Strong Gröbner bases and cyclic codes over a finite-chain ring, in Proc. Workshop on Coding and Cryptography, Paris, Electronic Notes in Discrete Mathematics, Vol. 6 (Elsevier Science, 2001), pp. 391–401] have presented an algorithm for computing Gröbner bases over finite-chain rings. Byrne and Fitzpatrick [Gröbner bases over Galois rings with an application to decoding alternant codes, J. Symbolic Comput.31 (2001) 565–584] have simultaneously proposed a similar algorithm for computing Gröbner bases over Galois rings (a special kind of finite-chain rings). However, they have not incorporated Buchberger's criteria into their algorithms to avoid unnecessary reductions. In this paper, we propose the adapted version of these criteria for polynomials over finite-chain rings and we show how to apply them on Norton–Sălăgean algorithm. The described algorithm has been implemented in Maple and experimented with a number of examples for the Galois rings.
GROUP CODES OVER NON-ABELIAN GROUPS
Authors: PILLADO CRISTINA GARCÍA , GONZÁLEZ SANTOS , MARTÍNEZ CONSUELO , MARKOV VICTOR , NECHAEV ALEXANDER
Published: February 2013

Let G be a finite group and F a field. We show that all G-codes over F are abelian if the order of G is less than 24, but for F = ℤ5 and G = S4 there exist non-abelian G-codes over F, answering to an open problem posed in [J. J. Bernal, Á. del Río and J. J. Simón, An intrinsical description of group codes, Des. Codes Cryptogr.51(3) (2009) 289–300]. This problem is related to the decomposability of a group as the product of two abelian subgroups. We consider this problem in the case of p-groups, finding the minimal order for which all p-groups of such order are decomposable. Finally, we study if the fact that all G-codes are abelian remains true when the base field is changed.
NOTES ON LIE IDEALS OF SIMPLE ARTINIAN RINGS
Authors: ARIANNEJAD M. , EMAMI M.
Published: February 2013

Let R be a ring. If we replace the original associative product of R with their canonic Lie product, or [a, b] = ab - ba for every a, b in R, then R would be a Lie ring. With this new product the additive commutator subgroup of R or [R, R] is a Lie subring of R. Herstein has shown that in a simple ring R with characteristic unequal to 2, any Lie ideal of R either is contained in Z(R), the center of R or contains [R, R]. He also showed that in this situation the Lie ring [R, R]/Z[R, R] is simple. We give an alternative matrix proof of these results for the special case of simple artinian rings and show that in this case the characteristic condition can be more restricted.
WEAK AB-CONTEXT FOR FP-INJECTIVE MODULES WITH RESPECT TO SEMIDUALIZING MODULES
Authors: HU JIANGSHENG , ZHANG DONGDONG
Published: February 2013

Let S and R be rings and SCR a semidualizing bimodule. We define and study GC-FP-injective R-modules, and these modules are exactly C-Gorenstein injective R-modules defined by Holm and Jørgensen provided that S = R is a commutative Noetherian ring. We mainly prove that the category of GC-FP-injective R-modules is a part of a weak AB-context, which is dual of weak AB-context in the terminology of Hashimoto. In particular, this allows us to deduce the existence of certain Auslander–Buchweitz approximations for R-modules with finite GC-FP-injective dimension. As an application, a new model structure in Mod R is given.
INVESTIGATION OF THE EXCHANGE REACTIONH + H′S → HS + H′ON THE1A′STATE POTENTIAL ENERGY SURFACE
Authors: JI LIN-BO , XIE TING-XIAN , WANG HONG-YAN
Published: February 2013

The quantum time dependent wave packet (TDWP) and quasiclassical trajectory (QCT) calculations were carried out to study the exchange reaction H(2S) + H′S(2Π) → HS(2Π) + H′(2S) on the1A′potential energy surface (PES). The integral cross sections of the H + H′S (v = j = 0) → HS + H′reaction calculated by the two methods were presented. The results reveal that the integral cross sections (ICS) decrease with the collision energy increasing. The result of the QCT calculations is reasonably consistent with the time-dependent wave packet. Moreover, the differential cross sections (DCS) were calculated by the QCT method at the four different collision energies, which display a forward–backward symmetry. A long-lifetime H2S intermediate complex of the exchange reaction was found according to the trajectories. In the stereodynamics investigation, the polar and dihedral angle distribution functions were calculated, which have the distinct oscillations. The oscillations could be attributed to the deep well on the1A′PES. However, based on the polar-angle and dihedral angle distribution functions, it could be predicted that the main product rotational angular momentum preferentially point to the positive or negative direction of y-axes.
THEORETICAL INVESTIGATION ON THE STRUCTURE AND PROPERTIES OF ALUMAZINE⋯M COMPLEXES (M=Li+,Na+,K+,Be2+,Mg2+, ANDCa2+)
Authors: RASEKH MAHTAB FATHI
Published: February 2013

The nature of alumazine⋯M ( M = Li+, Na+, K+, Be2+, Mg2+, AND Ca2+) interactions was studied by ab initio calculations. The interaction energies were calculated at MP2/6-311++G(d,p)//B3LYP/6-311++G(d,p) level. The calculations suggest that the size and charge of cation are two important factors that affect the interaction energy, charge transfer values and the variation in aromaticity of alumazine ring upon complexation. The theory of atoms in molecules (AIM) and natural bond orbital (NBO) analyses of complexes indicate that the variation of densities and the extent of charge shifts upon complexation correlate well with the obtained interaction energies. Finally, nucleus independent chemical shift (NICS) method was applied for evaluating the variation in aromaticity of alumazine ring upon complexation.
OPTICAL MEASUREMENTS OF RAT MUSCLE SAMPLES UNDER TREATMENT WITH ETHYLENE GLYCOL AND GLUCOSE
Authors: OLIVEIRA LUÍS , CARVALHO MARIA INÊS , NOGUEIRA ELISABETE , TUCHIN VALERY V.
Published: February 2013

With the objective to study the variation of optical properties of rat muscle during optical clearing, we have performed a set of optical measurements from that kind of tissue. The measurements performed were total transmittance, collimated transmittance, specular reflectance and total reflectance. This set of measurements is sufficient to determine diffuse reflectance and absorbance of the sample, also necessary to estimate the optical properties. All the performed measurements and calculated quantities will be used later in inverse Monte Carlo (IMC) simulations to determine the evolution of the optical properties of muscle during treatments with ethylene glycol and glucose. The results obtained with the measurements already provide some information about the optical clearing treatments applied to the muscle and translate the mechanisms of turning the tissue more transparent and sequence of regimes of optical clearing.
RECENT ADVANCES IN SODIUM INTERCALATION POSITIVE ELECTRODE MATERIALS FOR SODIUM ION BATTERIES
Authors: XU JING , LEE DAE HOE , MENG YING SHIRLEY
Published: February 2013

Significant progress has been achieved in the research on sodium intercalation compounds as positive electrode materials for Na-ion batteries. This paper presents an overview of the breakthroughs in the past decade for developing high energy and high power cathode materials. Two major classes, layered oxides and polyanion compounds, are covered. Their electrochemical performance and the related crystal structure, solid state physics and chemistry are summarized and compared.
SYNTHESIS OF SUB-10 NM TiO2 NANOWIRES FOR THE APPLICATION OF DYE-SENSITIZED SOLAR CELLS
Authors: LIU JUN , LIU ZHEN , LIN KANGBAO , WEI AIXIANG
Published: February 2013

Highly oriented single-crystalline rutile TiO2 nanowires on transparent conductive fluorine-doped tin oxide (FTO) substrates are prepared by low-temperature hydrothermal method. The small lattice mismatch between FTO substrate and rutile TiO2 promote the epitaxial nucleation and growth of rutile TiO2 nanowires on FTO, with the diameter of 4–6 nm. Due to Van der waals force, the ultrafine nanowires tend to gather together, forming nanowire bundles. Using the ultrafine nanowire bundle array as the photoanode and ruthenium complex (N719) as the sensitizer, dye-sensitized solar cells (DSSCs) are assembled. The effect of the TiO2 nanowire gathering on the power conversion of the DSSCs has been investigated. Experimental result shows that the light-to-electricity conversion efficiency is increased by reducing the gathering of the nanowires through introducing toluene into reactant precursors. The DSSCs based on the bundles with smallest average width (i.e., least nanowire gathering) show the highest power conversion efficiency of 3.70%. The relatively high energy conversion efficiency is contributed to the large surface area, which enhances the adsorption of dye molecules.
PROGRESS ON ANISOTROPIC MAGNETORESISTANCE EFFECT IN PEROVSKITE MANGANITES
Authors: YANG HUALI , LIU YIWEI , LI RUN-WEI
Published: February 2013

Anisotropic magnetoresistance (AMR) effect has been discovered over one century, but keeps attracting people's special attention due to its wide applications in magnetic devices as well as its intimate relationship with the most fascinating physics such as spin–orbit interaction and spin–charge coupling. In this review article, we introduce the general characters and tuning methods of AMR effect in perovskite manganites, the typical strongly correlated electron system, and discuss the possible mechanisms behind. Outlooks of the AMR effects in manganites and related devices are also addressed.
SPIN POLARIZED TRANSPORT IN Cd1-xMnxTe
Authors: SHARMA ASHUTOSH , NIMJE SWETALI , SALIMATH AKSHAY , GHOSH BAHNIMAN
Published: February 2013

Spin relaxation process is simulated for nanowires and 2-D channels composed of II–VI DMS materials, particularly for Cd 1-x Mn x Te , in our work. Our studies are focused on analyzing spin relaxation behavior at T = 1 K. Variations in spin relaxation length with applied field and concentration of Mn doping are calculated and plotted. Effect of one-magnon scattering process is significant due to magnetic nature of the materials and is demonstrated in this work.
Geologically-based permeability anisotropy estimates for tidally-influenced reservoirs using quantitative shale data
Authors: Burton D. , Wood L.J.
Published: February 2013

The effect of the vertical to horizontal permeability ratio (

k
v

 /

k
h

) on many displacement properties is significant, making it an important parameter to estimate for reservoir models. Simple ‘streamline’ models have been developed which relate

k
v

 /

k
h

at the reservoir scale to shale geometry, fraction and vertical frequency. A limitation of these models, especially for tidally-influenced reservoirs, is the lack of quantitisative geological inputs.

To address this lack of data, detailed shale characteristics were measured, using Lidar point clouds, from four different tidally-influenced reservoir analogues: estuarine point bar (McMurray Formation, Alberta, Canada), tidal sand ridge (Tocito Sandstone, New Mexico), as well as both unconfined and confined tidal bars (Sego Sandstone, Utah). Estuarine point bars have long (
x̄
  = 67.8 m) shales that are thick and frequent relative to the other units. Tidal sand ridges have short shales (
x̄
  = 8.6 m dip orientation) that are thin and frequent. Confined tidal bars contain shales that are thin, infrequent and anisotropic (x–  = 16.3 m dip orientation). Unconfined tidal bars contain nearly equidimensional shales of intermediate length (
x̄
 = 18.6 m dip orientation) with moderate thicknesses and vertical frequency.

The unique shale character of each unit results in a different distribution of estimated

k
v 

/

k
h

values. Estuarine point bars have lower average

k
v

/

k
h

values (
x̄
  = 8.2 ×10
−4
) than any other setting because of the long shales they contain. Tidal sand ridges have short, but frequent shales, which results in moderate

k
v 

/

k
h

estimates (
x̄
  = .011). Estimates of

k
v

/

k
h

are typically highest in confined tidal bars (
x̄
  = .038), which contain anisotropic and infrequent shales. Unconfined tidal bars have moderate lengths and frequency resulting in

k
v

/

k
h

estimates averaging 0.004. The results of this study highlight the link between heterogeneity, reservoir architecture and flow parameters.
Sedimentology and stratigraphy of an intra-cratonic basin coal seam gas play: Walloon Subgroup of the Surat Basin, eastern Australia
Authors: Martin M.A. , Wakefield M. , MacPhail M.K. , Pearce T. , Edwards H. E.
Published: February 2013

Large gas reserves are trapped in the coals of the Middle Jurassic (Callovian) Walloon Subgroup (lower part of the Injure Creek Group) in the Surat Basin, eastern Australia. The series is divided into the Juandah Coal Measures (upper), Tangalooma Sandstone and Taroom Coal Measures (lower). The upper and lower units are locally further subdivided. These economically important coals were deposited in an alluvial plain setting within an interior basin, which has no recorded contemporaneous marine influence. The coals are typically bituminous, perhydrous and low rank with a high volatile content. Despite individual ply (bench) thicknesses typically less than a metre, series of plies or seams of coals up to 10 m thick have historically been tentatively correlated across the entire play area (over 150 km).
Integrated tectonic basin modelling as an aid to understanding deep-water rifted continental margin structure and location
Authors: Roberts Alan M. , Kusznir Nick J. , Corfield Richard I. , Thompson Mark , Woodfine Richard
Published: February 2013

An integrated workflow has been devised for the investigation of deep-water rifted continental margins. At a margin this allows us to predict the crustal structure, the distribution of continental-lithosphere thinning and the location of the ocean–continent transition with a new degree of confidence. The workflow combines the analytical techniques of 2D or 3D gravity inversion, 2D or 3D flexural backstripping with reverse thermal subsidence modelling, upper-crustal fault analysis and rifted margin forward modelling. No one technique on its own can provide all of the required answers, nor can it provide answers without some degree of uncertainty. The use of a combination of techniques, however, provides answers to several different problems and, crucially, more confidence in these answers.

The workflow provides direct information on the present-day geometry of rifted margins and leads towards a better understanding of the geodynamic evolution of these margins. It also provides information which can inform the exploration process by making predictions about crustal structure at the ocean–continent transition, the location of the continent–ocean boundary, stretching-factor, heat-flow magnitude and history, palaeobathymetric history and subsurface palaeostructure. Application of the workflow is illustrated here with reference to the continental margins of West India, Brazil, West Australia, Norway and Newfoundland–Iberia.
Social Networks and Political Participation
Authors: Campbell David E.
Published: February 2013

In recent years, the study of political participation has benefited from growing attention to the study of social networks. Historically, most explanations for political participation have focused on characteristics of individuals. Although these individual-level correlates do a “pretty good” job of predicting who participates, incorporating social networks deepens our understanding of the factors that lead people to express voice in the democratic process. Even though the participation literature has long been split between scholars who favor a focus on individuals and others who emphasize social networks, the two approaches need not be in tension. Instead, they complement one another. The individualistic factors known to correlate with participation—including education, religious attendance, political knowledge, political conviction, and civic duty—all have a social dimension.
Stromal cells participate in the murine esophageal mucosal injury response
Authors: Shaker Anisa , Binkley Jana , Darwech Isra , Swietlicki Elzbieta , McDonald Keely , Newberry Rodney , Rubin Deborah C.
Published: February 2013

We identified α-smooth muscle actin (α-SMA)- and vimentin-expressing spindle-shaped esophageal mesenchymal cells in the adult and neonate murine esophageal lamina propria. We hypothesized that these esophageal mesenchymal cells express and secrete signaling and inflammatory mediators in response to injury. We established primary cultures of esophageal mesenchymal cells using mechanical and enzymatic digestion. We demonstrate that these primary cultures are nonhematopoietic, nonendothelial, stromal cells with myofibroblast-like features. These cells increase secretion of IL-6 in response to treatment with acidified media and IL-1β. They also increase bone morphogenetic protein (Bmp)-4 secretion in response to sonic hedgehog. The location of these cells and their biological functions demonstrate their potential role in regulating esophageal epithelial responses to injury and repair.