bluuebunny/crossref_metadata_2025 huggingface dataset:
The uncertainty of Late Pleistocene range expansions in the western Mediterranean: a case study of the colonization of south‐eastern Spain by the spur‐thighed tortoise, Testudo graeca
Authors: Graciá Eva , Giménez Andrés , Anadón José Daniel , Harris D. James , Fritz Uwe , Botella Francisco
Published: November 2012

Aim

Recent biogeographical studies have postulated a North African, Late Pleistocene, origin for some species of the Iberian Peninsula. However, a robust assessment of such range expansions requires high‐resolution molecular tools to resolve overlapping biogeographical and cultural processes. Here we aim to determine whether the spur‐thighed tortoise, Testudo graeca, arrived in south‐eastern Spain during historical or prehistoric times, and whether its dispersal to the Iberian Peninsula was human‐mediated.

Location

The western Mediterranean Basin (south‐eastern Spain, northern Algeria and north‐western Morocco).

Methods

Using 428 samples from 19 sites in North Africa and 18 in south‐eastern Spain, we obtained mitochondrial sequences from the cytochrome b gene and genotypes derived from seven microsatellite loci. These data were employed to obtain population genetics descriptors, haplotype networks, Bayesian cluster analyses and isolation‐by‐distance patterns. Moreover, we used a Bayesian demographic approach to delimit the dates involved in the range expansion.

Results

We found lower levels of genetic variability and weak mitochondrial differentiation in the south‐eastern Spanish tortoises compared with the North African ones. However, exclusive haplotypes occurred in the Iberian samples and microsatellite cluster analyses revealed moderate levels of admixture across both sides of the Mediterranean. A coastal area in the west of Algeria and the central‐southern region in south‐eastern Spain are suggested as the most probable founder and arrival places, respectively. Finally, we identified signatures of an ancient bottleneck event approximately 20,000–30,000 years ago.

Main conclusions

The spur‐thighed tortoise probably arrived in south‐eastern Spain during Late Pleistocene sea‐level low stands. The role that humans may have played as dispersers across the Mediterranean remains unclear. Our results are in accordance with other recent findings of trans‐Mediterranean expansions during this period and highlight the importance of employing precise methodological approaches before a species can be considered as historically introduced.
Living in Parallel Universes? Implementing European Movable Cultural Heritage Policy in Bulgaria
Authors: Dimitrova Antoaneta , Steunenberg Bernard
Published: November 2012

This article proposes an analytical model of implementation that is used to examine the implementation of the European Union's cultural heritage policy in Bulgaria. It begins by outlining a rational choice framework conceptualizing implementation as a three‐stage game with key roles for an enforcer, domestic policy‐makers and implementing actors. This model is then applied to the case of transposition and implementation of the EU rules regarding cultural heritage in Bulgaria. Different implementation outcomes stemming from one and the same formal policy are found. To explain the variation of implementation outcomes, the theorized model is applied and it is found that, given the high levels of polarization between political decision‐makers, the implementing actors have broad discretion to apply different informal policies. The analysis of implementation also shows that under these conditions implementing players have followed their normative orientations to apply different policies as if they live in parallel universes of implementation.
Abutment Emergence Modification for Immediate Implant Provisional Restorations
Authors: Schoenbaum Todd R. , Chang Yi‐Yuan , Klokkevold Perry R. , Snowden John S.
Published: November 2012

In their stock form, some titanium provisional implant abutments are not ideally designed for use in immediate placement/immediate provisional restoration treatment. This is largely due to the apical flare design that applies excessive pressure to the peri‐implant soft tissue complex and crestal bone. This appears to have the undesirable effect of increasing peri‐implant bone resorption and severely impeding the potential for increases in gingival volume. This type of stock titanium abutment will therefore benefit significantly from recontouring. The subgingival portion of the abutment is recontoured from the flared stock shape to a straight or parallel design. This modification minimizes pressure on the surgical site and provides additional space around the subgingival portion of the provisional restoration, within which the gingiva has the potential to remodel and fill. This allows the potential formation of additional peri‐implant gingival volume and a coronal maintenance or migration of the soft tissue complex. In order to minimize the “graying effect” of titanium abutments, the retentive portion is opaqued by the technician or clinician. These modifications will improve the potential outcomes for both the peri‐implant gingiva and the provisional restoration.

Clinical Significance

Narrowing the emergence profile of implant abutments for use in immediate implant provisional restorations appears to allow for creation of greater peri‐implant volume. Thus resulting in increased esthetic potential and predictability of the peri‐implant gingiva.
TGF‐β1, Smad‐2/‐3, Smad‐1/‐5/‐8, and Smad‐4 signaling factors are expressed in ameloblastomas, adenomatoid odontogenic tumors, and calcifying cystic odontogenic tumors: an immunohistochemical study
Authors: Karathanasi Vasiliki , Tosios Konstantinos I. , Nikitakis Nikolaos G. , Piperi Evangelia , Koutlas Ioannis , Trimis George , Sklavounou Alexandra
Published: November 2012

Objectives

The TGF‐β/Smad signaling pathway regulates diverse cellular functions, including tooth development, and is involved in numerous pathological processes such as tumorigenesis. The aim of this study was to investigate the immunoexpression of the TGF‐β/Smad signaling pathway members in ameloblastoma (AM), calcifying cystic odontogenic tumor (CCOT), and adenomatoid odontogenic tumor (AOT).

Materials and methods

This retrospective cross‐sectional study included 65 tissue specimens: 34 AMs, 13 CCOTs, and 18 AOTs. Serial sections were immunohistochemically stained with TGF‐β1, Smad‐4, Smad‐1/‐5/‐8, and Smad‐2/‐3 antibodies, and a semiquantitative measurement of the positive cells was carried out by two oral pathologists using a 0–3 scale (0: no immunoreactivity, 1: <20% positive cells, 2: 20–50% positive cells, 3: >50% positive cells).

Results

All biomarkers studied were found significantly decreased in AM compared to CCOT and AOT. AOT and CCOT expressed Smad‐1/‐5/‐8 more strongly compared to AM (OR = 11.66, P < 0.001 and OR = 5.34, P = 0.013, respectively), and Smad‐2/‐3 immunostaining was found significantly increased in CCOT (OR = 10.42, P = 0.001) and AOT (OR = 5.16, P < 0.004) compared to AM. Similarly, Smad‐4 was expressed more strongly in AOT and CCOT compared to AM (P = 0.001), while AOT demonstrated a fivefold higher chance to express TGF‐β1 compared to AM (P = 0.011).

Conclusion

TGF‐β/Smad signaling pathway is activated in AM, AOT, and CCOT. The statistically significant reduced TGF‐β1/Smad immunoexpression in AM compared to AOT/CCOT could be associated with the more aggressive biological behavior of AM including increased cell proliferation and reduced apoptosis and differentiation. Thus, the biomarkers TGF‐β, Smad‐4, Smad‐1/‐5/‐8, and Smad‐2/‐3 could serve as supplementary diagnostic indices between odontogenic tumors of high and low neoplastic dynamics.
Productive Ward initiative promotes better communication between mental health teams and ensures timely discharge for patients
Authors: Lennard C.
Published: November 2012

Accessible summary

This paper discusses how an acute inpatient unit has implemented the ‘Productive Ward’ initiative, and utilized three of the Productive Ward Modules – Ward Round, Admissions and Planned Discharge, and Patient Status At a Glance – to promote better communication and working between inpatient nursing and medical teams, Home Treatment Team and Community Mental Health Team (CMHT), as they endeavour to ensure timely discharge for patients.

Using the Patient Status At a Glance board to make information on patient status clear and immediate, nursing staff have begun utilizing the Zoning system for managing and targeting nursing resources – a red, amber and green traffic light system, which identifies and categorizes patient risk on a daily basis.

Ward staff have initiated a daily ‘Rapid Review’ of patients, a tightly focused meeting, involving the ward nursing staff, the Inpatient Medical Team, the Home Treatment Team and the CMHT to discuss allocation of Care Co‐ordinators, and to identify accommodation issues and other potential blocks to timely discharge.

The Productive Ward is an initiative whereby nursing staff are empowered to bring about changes in the workplace to streamline systems and release time to care for patients. It is an evidence‐based approach, which brings about improved clinical and safety outcomes. This paper discusses how three of the Productive Ward Modules – Ward Round, Admissions and Planned Discharge, and Patient Status At a Glance – have meshed to promote better communication and working between inpatient nursing and medical teams, Home Treatment Team and Community Mental Health Team, and to endeavour to ensure timely discharge for patients.
Overexpression of the phosphatidylinositol synthase gene (ZmPIS) conferring drought stress tolerance by altering membrane lipid composition and increasing ABA synthesis in maize
Authors: LIU XIUXIA , ZHAI SHUMEI , ZHAO YAJIE , SUN BAOCHENG , LIU CHENG , YANG AIFANG , ZHANG JUREN
Published: November 2012

In this study, the ZmPIS gene with a maize ubiquitin promoter was introduced into maize (Zea mays L.) inbred line DH4866 by an Agrobacterium‐mediated method to explore the function of the ZmPIS gene in the response of maize to drought stress. The overexpression of ZmPIS in maize resulted in significantly elevated levels of most phospholipids, galactolipids in leaves compared with those in WT and markedly up‐regulated expression of some genes involved in the phospholipids metabolism pathway and the ABA biosynthesis pathway after drought stress. Consistent with these results, the drought stress tolerance of the ZmPIS sense transgenic plants were enhanced significantly compared to WT maize plants. These results imply that ZmPIS regulate the plant response to drought stress through altering membrane lipid composition and increasing ABA synthesis in maize.
Neonatal stroke associated with de novo antiphospholipid antibody and homozygous 1298C/C methylenetetrahydrofolate reductase mutation
Authors: Rego Sousa Paulo , Figueira Ricardo , Vasconcellos Rui
Published: November 2012

Antiphospholipid antibodies are a recognised prothrombotic risk factor associated with acute ischaemic infarction. Most autoimmune diseases are rare in infants, and in the neonatal period, autoimmunity is related to transplacental passage of maternal immunoglobulin G autoantibodies. Distinguishing between de novo and acquired autoimmunity has important therapeutic implications and is crucial for determining the prognosis. We present a case of a neonatal thrombotic stroke associated with de novo synthesis of antiphospholipid antibodies, a homozygous 1298C/C methylene-tetrahydrofolate reductase mutation and a double-homozygous plasminogen activator inhibitor 1 polymorphism (PAI-1 844A/A and 675 4G/4G), which may have increased the final thrombotic risk. Her mother was not positive for antiphospholipid antibodies. The authors highlight an unequivocal evidence of a de novo case of paediatric antiphospholipid antibody syndrome and emphasise the need for a thorough investigation in cases of neonatal stroke including molecular thrombophilia study.
Isolated hepatic artery injury in blunt abdominal trauma presenting as upper gastrointestinal bleeding: treatment with transcatheter embolisation
Authors: Taslakian Bedros , Ghaith Ola , Al-Kutoubi Aghiad
Published: November 2012

Liver injury in blunt abdominal trauma is common. However, not often does blunt trauma cause injury to the anatomical structures of the porta hepatis. Isolated injury of the hepatic artery has been rarely reported in the literature. Such injury may be lethal and requires immediate diagnosis and management. This report describes an unusual case of blunt abdominal trauma resulting in hepatic and gastroduodenal artery dissection, with pseudoaneurysm formation complicated by active upper gastrointestinal bleeding. The injury was managed by transcatheter embolisation. Awareness of this diagnosis should facilitate management of similar trauma cases.
Use of a coronary sinus guiding sheath for placement of right ventricular lead in abnormal venous anatomy: a report of 2 cases
Authors: Vivek G , shetty Ranjan K , Pai Umesh M , Nayak Krishnananda
Published: November 2012

Techniques of implanting pacing leads in the right ventricle (RV) have evolved over time and involve the use of preshaped stylets. However, in the presence of venous abnormalities, it could be very challenging to do the same. We describe two cases with complex superior vena caval (SVC) anatomy which could be negotiated only with the use of a slittable coronary sinus guiding sheath and successful placement of pacing lead in the right ventricle.
Uptake of methylnaltrexone in Australian patients with opioid-induced constipation: a review of the number of prescriptions presented in the first 12 months of subsidisation
Authors: Clark Katherine , Rowett Debra , Robinson Maxine , Currow David C
Published: November 2012

Background

Disturbed bowel habits are very common in palliative care patients, most commonly thought to be due to opioid use. The peripheral opioid-antagonist methylnaltrexone has been subsidised in Australia to ensure that palliative care patients have timely and equitable access to this medication. The aim of this paper is to describe the use of methylnaltrexone in the first year after it was subsidised for palliative care, in particular focusing on the actual use of this medication compared with predicted need.

Methods

The predicted need for methylnaltrexone was calculated using an epidemiological approach based on data collected by the Australian Institute of Health and Welfare to determine the number of Australian deaths annually. A single source of data was used to determine the number of patients who die while under the care of palliative services in Australia (National Census of Palliative Care Services, 1999). These figures allowed the number of people likely to be receiving opioids to be estimated and therefore the number who could potentially benefit from methylnaltrexone.

Results

The number of patients who might benefit was calculated to be 5000, which contrasts with the 261 actual prescriptions written for methylnaltrexone. Even more striking was the disparity between initial prescriptions and the 93 requests for ongoing use.

Conclusions

These data highlight much lower use of methylnaltrexone than predicted and raise a number of questions including the fact that the palliative care literature emphasises opioids as the dominant cause of constipation in palliative care patients given little ongoing use of methylnaltrexone.
Ocular disease in working horses in Ethiopia: a cross‐sectional study
Authors: Scantlebury C. E. , Aklilu N. , Reed K. , Knottenbelt D. C. , Gebreab F. , Pinchbeck G. L.
Published: November 2012

Ocular disease is a frequent finding in working horses. This study aimed to estimate the prevalence and types of ocular pathology, and explore risk factors potentially associated with disease within a population of working horses in Ethiopia. In total, 1049 horses were selected from horses attending clinics run by the Society for Protection of Animals Abroad (SPANA). Each had an ophthalmic examination conducted under field conditions using a pen‐torch. All owners completed a short questionnaire. The prevalence of ocular abnormalities was 23.5 per cent (95 per cent confidence interval (CI) 18.0 per cent to 30.1 per cent) and the percentage of horses with an abnormality in at least one eye was 43 per cent (95 per cent CI 28.7 per cent to 58.4 per cent), although this varied between towns. Mild eye pathology and end‐stage disease with irreversible pathology were most common. There were significantly more eye abnormalities in the right eye compared with the left, and older horses were more likely to have ocular pathology. Only 55.1 per cent of owners had noticed there was an ocular abnormality present, and only 2.2 per cent had received any previous treatment for eye disease. Only 1.9 per cent presented to the clinic because of an eye problem. There appears to be either a lack of owner awareness, or a low perception of the importance of eye disease among owners.
CONSTRUCTING SCALE-FREE NETWORKS WITH A GIVEN CLUSTER COEFFICIENT
Authors: ARIAPOUR MOHAMMAD , OSKOEE EHSAN NEDAAEE
Published: November 2012

We introduce a new generation rule for local thresholding in scale-free networks based on the nodes' degree. The resulting networks are disassortative with a hierarchical structure. There is, however, a subnet of the nodes, which we call the active nodes, which is neither disassortative nor has such a structure. It is shown that networks with a wide range of cluster coefficients, ranging from very small to close to unity and with scaling exponent from 2.5 to 4 are generated by the new method, which mimic some important real-world networks.
MORE SPECIAL FUNCTIONS TRAPPED
Authors: SCHWARTZ CHARLES
Published: November 2012

We extend the technique of using the trapezoidal rule for efficient evaluation of the special functions of mathematical physics given by integral representations. This technique was recently used for Bessel functions, and here we treat incomplete gamma functions and the general confluent hypergeometric function.
EFFECTIVE POTENTIAL FOR LIFSHITZ-TYPE z = 3 GAUGE THEORIES
Authors: FARAKOS K.
Published: November 2012

We consider the one-loop effective potential at zero temperature in Lifshitz-type field theories with anisotropic space–time scaling, with critical exponent z = 3, including scalar, fermion and gauge fields. The fermion determinant generates a symmetry breaking term at one loop in the effective potential and a local minimum appears, for nonzero scalar field, for every value of the Yukawa coupling. Depending on the relative strength of the coupling constants for the scalar and the gauge field, we find a second symmetry breaking local minimum in the effective potential for a bigger value of the scalar field.
STUDY OF THE CONDUCTIVITY OF DIELECTRIC UNDER HIGH ENERGY ELECTRON IRRADIATION
Authors: CHEN YIFENG , YANG SHENGSHENG , LI DETIAN , QIN XIAOGANG , LIU QING , TANG DAOTANG , FENG NA , SHI LIANG , ZHANG LEI
Published: November 2012

High energy electron irradiation was performed on a theoretical and experimental study of the dielectric conductivity. This paper presents a theoretical method to the determination of the conductivity of dielectric materials under irradiation, and the conductivity of kapton is measured under 0.8 MeV electron irradiation. The results from theory and experiment clearly illustrate the expected dependence of conductivity of dielectric on dose rate, and the resistance of kapton decreases in 102.
DYNAMICS OF AVALANCHE QUANTUM DOT INFRARED PHOTODETECTORS
Authors: ZAVVARI MAHDI , AHMADI VAHID
Published: November 2012

Time and frequency response of an avalanche quantum dot infrared photodetector (A-QDIP) operating at long infrared (IR) wavelengths is calculated and the effect of its structure on the dynamic behavior is studied. For this purpose, the rate equations of different regions are numerically solved considering the boundary conditions. Results show that detector with long multiplication region has a slower time response. Also frequency analysis predicts a 3-dB bandwidth above 100 GHz for a device with multiplication length of 200 nm. Gain bandwidth product (GBP) is calculated and a value of about 1000 GHz is obtained. Effect of charge layer doping on dynamic response of detector is also studied and results show that increase in doping improves the GBP while the bandwidth is reduced. We also study the effect of quantum dots of absorption region on frequency response of device and results show that longer electron relaxation time into quantum dot decreases the bandwidth of detector.
ON REPRESENTATIONS OF 2-BRIDGE KNOT GROUPS IN QUATERNION ALGEBRAS II: THE CASE OF THE TREFOIL KNOT GROUP
Authors: HILDEN HUGH M. , LOZANO MARÍA TERESA , MONTESINOS-AMILIBIA JOSÉ MARÍA
Published: November 2012

The complete classification of representations of the Trefoil knot group G in S3 and SL(2, ℝ), their affine deformations, and some geometric interpretations of the results, are given. Among other results, we also obtain the classification up to conjugacy of the noncyclic groups of affine Euclidean isometries generated by two isometries μ and ν such that μ2 = ν3 = 1, in particular those which are crystallographic. We also prove that there are no affine crystallographic groups in the three-dimensional Minkowski space which are quotients of G.
THE MILNOR $\bar{\mu}$ INVARIANTS AND NANOPHRASES
Authors: KOTORII YUKA
Published: November 2012

Two link diagrams are link homotopic if one can be transformed into the other by a sequence of Reidemeister moves and self-crossing changes. Milnor introduced invariants under link homotopy called [Formula: see text]. Nanophrases, introduced by Turaev, generalize links. In this paper, we extend the notion of link homotopy to nanophrases. We also generalize [Formula: see text] to the set of those nanophrases that correspond to virtual links.
BROWNIAN MOTION WITH ADHESION: LINEAR AND QUADRATIC NOISE
Authors: GITTERMAN M.
Published: November 2012

We consider a new type of the Brownian motion, in which the surrounding molecules are capable not only of colliding with the Brownian particle, but also of adhering to the Brownian particle for some time, thereby randomly changing its mass. The second moment, 〈v2〉, becomes negative either due to the large strength of the mass fluctuations or due to the large amplitude of an external periodic field indicating an instability of the system, which cannot reach the stationary state.
THE TIMING OF PORTFOLIO ADJUSTMENTS: A REGIME-SWITCHING APPROACH
Authors: FAN GUOBIN , ZENG YONG
Published: November 2012

The fact that the relationships among the returns of financial assets tend to be nonlinear and time-varying has important implications for asset allocation. To describe these two features, this paper first combines a copula function with the Markov switching technique to model the dependence structure across assets and then builds on this Markov Switching Copula model to present a procedure for the timing of portfolio adjustments. Our empirical evidence confirms that the dependence structure between high-risk and low-risk stocks in the Shanghai and Shenzhen markets is not static but switches between regimes over the course of the sample horizon considered in this paper. More importantly, as a result of such regime-switching characteristics of their dependence structure, our analysis of the out-of-sample asset allocation performance indicates that employing the procedure proposed in this paper to identify regime changes and decide when to adjust portfolio weights allows investors with the Constant Relative Risk Aversion utility to achieve both higher realized returns and higher certainty equivalent rate of returns than does the use of strategies based on static models.
REINFORCEMENT LEARNING FOR DECISION-MAKING IN A BUSINESS SIMULATOR
Authors: GARCÍA JAVIER , BORRAJO FERNANDO , FERNÁNDEZ FERNANDO
Published: November 2012

Business simulators are powerful tools for both supporting the decision-making process of business managers as well as for business education. An example is SIMBA (SIMulator for Business Administration), a powerful simulator which is currently used as a web-based platform for business education in different institutions. In this paper, we propose the application of reinforcement learning (RL) for the creation of intelligent agents that can manage virtual companies in SIMBA. This application is not trivial, given the particular intrinsic characteristics of SIMBA: it is a generalized domain where hundreds of parameters modify the domain behavior; it is a multi-agent domain where both cooperation and competition among different agents can coexist; it is required to set dozens of continuous decision variables for a given business decision, which is made only after the study of hundreds of continuous variables. We will demonstrate empirically that all these challenges can be overcome through the use of RL, showing results for different learning scenarios.
EFFICIENCY ANALYSIS OF PROVINCIAL DEPARTMENTS OF PHYSICAL EDUCATION IN IRAN
Authors: SOLEIMANI-DAMANEH JAHANGIR , SOLEIMANI-DAMANEH MAJID , HAMIDI MEHRZAD
Published: November 2012

In many countries, including Iran, Provincial Departments of Physical Education try to develop the athletic sports and sports for all in their related areas (state), using the government resources. Their success rate has always been an important subject for the top sports managers of country. In this paper we use data envelopment analysis (DEA) and analytic hierarchy process (AHP) techniques for analyzing the performance of physical education organizations in Iran. Some convex and nonconvex DEA models have been used. Afterwards, we have used the Shannon's entropy for aggregating the results obtained from different models and providing a final efficiency score (FES) and a unified ranking. It can be seen that, in the ranking approach provided in this paper the most productive scale size (MPSS) units have the best rank (see Proposition 1). Our findings reveal that the average of FESs of the states is 0.472635 and 50% of the states have an FES more than this average. Classifying the sates to five efficiency classes, "Excellent, Good, Middle, Weak and Very Weak", the percentage of the states belonging to these classes are 6.7, 30, 16.6, 36.7 and 10, respectively. Also, some correlation and difference studies have been carried out using the Pearson's correlation and student's t-tests. Finally, comparisons between the results of some relevant existing publications and those given in the present paper are addressed.
EFFICIENTLY MINING HIGH AVERAGE-UTILITY ITEMSETS WITH AN IMPROVED UPPER-BOUND STRATEGY
Authors: LAN GUO-CHENG , HONG TZUNG-PEI , TSENG VINCENT S.
Published: November 2012

Utility mining has recently been discussed in the field of data mining. A utility itemset considers both profits and quantities of items in transactions, and thus its utility value increases with increasing itemset length. To reveal a better utility effect, an average-utility measure, which is the total utility of an itemset divided by its itemset length, is proposed. However, existing approaches use the traditional average-utility upper-bound model to find high average-utility itemsets, and thus generate a large number of unpromising candidates in the mining process. The present study proposes an improved upper-bound approach that uses the prefix concept to create tighter upper bounds of average-utility values for itemsets, thus reducing the number of unpromising itemsets for mining. Results from experiments on two real databases show that the proposed algorithm outperforms other mining algorithms under various parameter settings.
AB INITIO AND DFT STUDY OF NON-COVALENT INTERACTIONS BETWEEN RARE GAS ATOMS AND AROMATIC RINGS
Authors: CHENG CHENG , ZHANG MIN , SHENG LI
Published: November 2012

In this paper, the weak interaction between aromatic rings (ARs) and rare gas (Rg) atoms has been studied using ab initio calculation and density functional theory (DFT). The augmented Dunning basis sets were used, and the convergence test was performed up to aug-cc-pV5Z. Among the computationally feasible methods, ωB97XD performed the best for these non-covalent systems. NBO analysis was performed to investigate the nature of the Rg/AR interactions. In this type of weak interaction, the induced and instantaneous dipole and charge transfer character both contribute to the interaction energies and equilibrium distances.
STRUCTURAL AND OPTICAL PROPERTIES OF EU3+-DOPED GaN NANOPARTICLES BASED FREEZE-DRIED PRECURSORS
Authors: EL HIMRI MAMOUNE , EL HIMRI ABDELOUAHAD
Published: November 2012

Europium (0.5% and 5%) doped GaN nanoparticles were successfully prepared by ammonolysis of the corresponding freeze-dried precursors. A single hexagonal phase with the wurtzite structure was obtained as determined by X-ray Powder Diffraction. The crystallite size determined by XRD was lower than 10 nm. Fluorescence line narrow spectra show excitation wavelength dependence, which is indicative that the Eu3+ ions are diluted in the GaN matrix. The environment distribution occupied by the Eu3+ ions has been analyzed by crystal-field calculation and the results are compared with those for other materials.
Bioavailability of nutrients in Australia from Mobile Metal Ion® analysis of catchment outlet sediment samples: continental-scale patterns and processes
Authors: Mann A. , de Caritat P. , Prince P.
Published: November 2012

Catchment outlet sediments (0–10 cm depth, sieved to <2 mm) collected at a very low density over most of the Australian continent have been analysed using the Mobile Metal Ion (MMI®) partial extraction technique. Of the 54 elements determined, eight are generally regarded as essential nutrients for plant growth: Ca, Cu, Fe, K, Mg, Mn, P and Zn. A further three, Mo, Ni and Se are considered significant micronutrients. Estimation of ‘bioavailability’ from MMI® analysis gives results comparable with standard agricultural measurements for many nutrients. Percentage ‘bioavailability’, operationally defined here as the ratio of MMI® concentration to total element concentration, has been investigated and ranges from 31% for Se to 0.1% for Fe. Smoothed (kriged) colour raster maps for continental Australia have been produced for these 11 nutrients and interpreted in terms of lithology (e.g. presence of carbonates in the MMI® Ca map), mineralization (e.g. known mineral districts in the Cu and Zn maps), environmental processes (e.g. salinity in K map, weathering and acid generation in Fe map) and agricultural practices (e.g. application of fertilizers in the MMI® P map). This first application of a partial extraction technique at the scale of a continent has yielded meaningful, coherent and interpretable results.
The Frederick Project: Geochemical exploration for sediment-hosted base metals in covered terrain in the Bangemall Basin, Western Australia
Authors: Mazzucchelli Richard H.
Published: November 2012

The Frederick Project involves greenfields exploration for concealed sediment-hosted Cu-Pb-Zn-Ag in the Meso-Proterozoic Bangemall Basin in NW Western Australia. Three different geochemical sampling media (groundwater, lag and soil) were used to progressively focus exploration from a regional anomaly identified from a low density (1 sample/16 sq. km) government survey to potential drilling targets. The application of multi-element partial digest soil geochemistry was found to be most effective in delineating bedrock mineralization signatures through extensive transported cover. Factor Analysis assisted in the initial identification of element associations representative of several distinct mineralizing and metasomatic events which have been imprinted on the area. Application of the Weighted Sums technique, based on the results of Factor Analysis, was useful to summarise multi-element data from a progressively expanding database. Drilling is required to document the thickness of the transported overburden and determine the economic significance of the geochemical anomalies located. However, the Frederick Project demonstrates the effectiveness of hydrogeochemistry, combined with multi-element partial digest soil geochemistry in delineating bedrock geochemical targets through alluvial cover.
Calcrete and plant inter-relationships for the expression of concealed mineralization at the Tunkillia gold prospect, central Gawler Craton, Australia
Authors: van der Hoek B. G. , Hill S. M. , Dart Robert C.
Published: November 2012

Transported and typically weathered material that extends over much of Australia presents a challenge for the successful application of surficial geochemical exploration methods. The Tunkillia Au-prospect in the Gawler Craton, South Australia provides a case study where unconsolidated and potentially laterally transported aeolian and alluvial sediments overlie a deeply weathered profile with variable supergene and primary Au mineralization at depths typically exceeding 40 m. The Tunkillia Au prospect was discovered through a regional calcrete sampling program, but elevated Au concentrations in this material do not always express underlying mineralization, such is the case at Tomahawk, an area of elevated Au in calcrete results overlying limited, low grade mineralization. The distribution and sampling accessibility of calcrete is also not continuous across the landscape, where in this region young siliciclastic linear dune ridges bury older calcrete that are otherwise exposed or only at shallow depths in dune swales or across sheetwash plains. Vegetation cover is more continuous across this landscape and is dominated by several main species. Sampling of dominant plant species:
Casuarina pauper
, and
Eucalyptus concinna
, has been conducted across Tomahawk where some sites of elevated Au in calcrete have been drilled. Results show a limited spatial association between calcrete geochemistry and plant biogeochemistry. This demonstrates that plant sampling is able to express low grade, discrete areas of buried Au mineralization typically on the scale of tens of metres, whereas the expression provided from calcrete is more levelled, and typically representative of larger areas, especially when they have formed within transported detritus host materials. It is recommended that although plant biogeochemistry and calcrete geochemistry may have their strengths and weaknesses, such as scale constraints, in regional geochemical exploration programs when these methods are integrated they potentially provide a more comprehensive and widely available geochemical exploration assessment across a wider range of regolith-landform settings.
The application of predictive geochemical modelling to determine backfill requirements at Turquoise Ridge Joint Venture, Nevada
Authors: Warrender Ruth , Bowell Rob , Prestia Amy , Barnes Andrew , Mansanares Wayne , Miller Mark
Published: November 2012

Predictive geochemical modelling has been carried out for the Turquoise Ridge and Valmy pits, Getchell gold mine, Nevada (USA) as part of an updated evaluation of waste rock management. The purpose of the modelling exercise was to predict the concentrations of solutes that may emanate from the waste rock backfilled pits and to assess the impact of any seepage from the pits on underlying groundwater chemistry. The results of the geochemical modelling will be used to assess the level of cover required for the backfilled pits in order to ensure that no degradation of groundwater occurs.

The assessment of geochemical reactivity was undertaken using laboratory column leaching utilizing alternating wet and dry cycles to simulate accelerated weathering in humidity cell tests (HCTs). The chemistry of the leaching solutions was used to develop source term solutions that were scaled from laboratory to field conditions and used as inputs for the geochemical models.

Geochemical modelling was carried out using the USGS-developed software PHREEQC. Seepage water quality predictions were made based on the mass load mixing of waters contacting different lithologies in each of the backfilled pits. Water quality predictions were then made for a number of seepage scenarios, including 1%, 5%, 10%, 50% and 100% of mean annual precipitation that will infiltrate the backfill and report as seepage to groundwater.

The results of the modelling exercise demonstrate that the impact of the pits on the underlying groundwater is largely dependent on the amount of seepage through the backfill. In general, significant changes in groundwater chemistry were noted when there was greater than 10% seepage from both the Turquoise Ridge and Valmy pits. Under the 100% seepage scenario, groundwater is likely to be characterised by elevated concentrations of arsenic, selenium, sulphate and manganese. However, the impact to groundwater will be negligible if less than 10% seepage occurs. This can be attained through placement of a thick alluvium cover on the backfill material and re-contouring of the area to natural topography.
Oligocene slow and Miocene–Quaternary rapid deformation and uplift of the Yumu Shan and North Qilian Shan: evidence from high-resolution magnetostratigraphy and tectonosedimentology
Authors: Fang Xiaomin , Liu Dongliang , Song Chunhui , Dai Shuang , Meng Qingquan
Published: November 2012

Most existing tectonic models suggest Pliocene–Quaternary deformation and uplift of the NE Tibetan Plateau in response to the collision of India with Asia. Within the NE Tibetan Plateau, growth of the terranes was suggested to progress northeastward with the Yumu Shan (mountain) at the northeasternmost corner of the Qilian Shan (mountains) being uplifted only since about 1 Ma ago. Here we present a detailed palaeomagnetic dating and tectonosedimentological measurement of Cenozoic sediments in the eastern Jiuquan Basin related to the deformation and uplift of the North Qilian Shan and Yumu Shan. The results show that the eastern Jiuquan Basin is a Cenozoic foreland basin and received sediments at about 27.8 Ma at the latest. Eight subsequent tectonic events at about 27.8, 24.6, 13.7–13, 9.8–9.6, 5.1–3.6, 2.8–2.6, 0.8 and 0.1 Ma demonstrate the development of the foreland basin in response to Oligocene–Quaternary uplift of the North Qilian Shan and subsequent propagation of thrust–fold system owing to collision of India with Asia. The Yumu Shan is the late phase of deformation front in the thrust–fold system and commenced rapid uplift at about 9.8–9.6 Ma at the latest. A rigid block-floating model is proposed to interpret the mechanism of this deformation and uplift history.
A comparison of exercise type and intensity on the noninvasive assessment of skeletal muscle mitochondrial function using near-infrared spectroscopy
Authors: Ryan Terence E. , Brizendine Jared T. , McCully Kevin K.
Published: November 2012

Near-infrared spectroscopy (NIRS) can be used to measure muscle oxygen consumption (mVO2) using arterial occlusions. The recovery rate of mVO2after exercise can provide an index of skeletal muscle mitochondrial function. The purpose of this study was to test the influence of exercise modality and intensity on NIRS measurements of mitochondrial function. Three experiments were performed. Thirty subjects (age: 18–27 yr) were tested. NIRS signals were corrected for blood volume changes. The recovery of mVO2after exercise was fit to a monoexponential curve, and a rate constant was calculated (directly related to mitochondrial function). No differences were found in NIRS rate constants for VOL and ES exercises (2.04 ± 0.57 vs. 2.01 ± 0.59 min−1for VOL and ES, respectively; P = 0.317). NIRS rate constants were independent of the contraction frequency for both VOL and ES (VOL: P = 0.166 and ES: P = 0.780). ES current intensity resulted in significant changes to the normalized time-tension integral (54 ± 11, 82 ± 7, and 100 ± 0% for low, medium, and high currents, respectively; P < 0.001) but did not influence NIRS rate constants (2.02 ± 0.54, 1.95 ± 0.44, 2.02 ± 0.46 min−1for low, medium, and high currents, respectively; P = 0.771). In summary, NIRS measurements of skeletal muscle mitochondrial function can be compared between VOL and ES exercises and were independent of the intensity of exercise. NIRS represents an important new technique that is practical for testing in research and clinical settings.
Vasoconstrictor responsiveness during hyperbaric hyperoxia in contracting human muscle
Authors: Casey Darren P. , Joyner Michael J. , Claus Paul L. , Curry Timothy B.
Published: November 2012

Large increases in systemic oxygen content cause substantial reductions in exercising forearm blood flow (FBF) due to increased vascular resistance. We hypothesized that 1) functional sympatholysis (blunting of sympathetic α-adrenergic vasoconstriction) would be attenuated during hyperoxic exercise and 2) α-adrenergic blockade would limit vasoconstriction during hyperoxia and increase FBF to levels observed under normoxic conditions. Nine male subjects (age 28 ± 1 yr) performed forearm exercise (20% of maximum) under normoxic and hyperoxic conditions. Studies were performed in a hyperbaric chamber at 1 atmosphere absolute (ATA; sea level) while breathing 21% O2 and at 2.82 ATA while breathing 100% O2 (estimated change in arterial O2 content ∼6 ml O2/100 ml). FBF (ml/min) was measured using Doppler ultrasound. Forearm vascular conductance (FVC) was calculated from FBF and blood pressure (arterial catheter). Vasoconstrictor responsiveness was determined using intra-arterial tyramine. FBF and FVC were substantially lower during hyperoxic exercise than normoxic exercise (∼20–25%; P < 0.01). At rest, vasoconstriction to tyramine (% decrease from pretyramine values) did not differ between normoxia and hyperoxia ( P > 0.05). During exercise, vasoconstrictor responsiveness was slightly greater during hyperoxia than normoxia (−22 ± 3 vs. −17 ± 2%; P < 0.05). However, during α-adrenergic blockade, hyperoxic exercise FBF and FVC remained lower than during normoxia ( P < 0.01). Therefore, our data suggest that although the vasoconstrictor responsiveness during hyperoxic exercise was slightly greater, it likely does not explain the majority of the large reductions in FBF and FVC (∼20–25%) during hyperbaric hyperoxic exercise.
Targeted Delivery of Paclitaxel to EphA2-Expressing Cancer Cells
Authors: Wang Si , Noberini Roberta , Stebbins John L. , Das Swadesh , Zhang Ziming , Wu Bainan , Mitra Sayantan , Billet Sandrine , Fernandez Ana , Bhowmick Neil A. , Kitada Shinichi , Pasquale Elena B. , Fisher Paul B. , Pellecchia Maurizio
Published: November 2012

Purpose: YSA is an EphA2-targeting peptide that effectively delivers anticancer agents to prostate cancer tumors. Here, we report on how we increased the drug-like properties of this delivery system.

Experimental Design: By introducing non-natural amino acids, we have designed two new EphA2 targeting peptides: YNH, where norleucine and homoserine replace the two methionine residues of YSA, and dYNH, where a D-tyrosine replaces the L-tyrosine at the first position of the YNH peptide. We describe the details of the synthesis of YNH and dYNH paclitaxel conjugates (YNH-PTX and dYNH-PTX) and their characterization in cells and in vivo.

Results: dYNH-PTX showed improved stability in mouse serum and significantly reduced tumor size in a prostate cancer xenograft model and also reduced tumor vasculature in a syngeneic orthotopic allograft mouse model of renal cancer compared with vehicle or paclitaxel treatments.

Conclusion: This study reveals that targeting EphA2 with dYNH drug conjugates could represent an effective way to deliver anticancer agents to a variety of tumor types. Clin Cancer Res; 19(1); 128–37. ©2012 AACR.
Cancer-Specific Requirement for BUB1B/BUBR1 in Human Brain Tumor Isolates and Genetically Transformed Cells
Authors: Ding Yu , Hubert Christopher G. , Herman Jacob , Corrin Philip , Toledo Chad M. , Skutt-Kakaria Kyobi , Vazquez Julio , Basom Ryan , Zhang Bin , Risler Jennifer K. , Pollard Steven M. , Nam Do-Hyun , Delrow Jeffery J. , Zhu Jun , Lee Jeongwu , DeLuca Jennifer , Olson James M. , Paddison Patrick J.
Published: November 2012

To identify new candidate therapeutic targets for glioblastoma multiforme, we combined functional genetics and glioblastoma network modeling to identify kinases required for the growth of patient-derived brain tumor–initiating cells (BTIC) but that are dispensable to proliferating human neural stem cells (NSC). This approach yielded BUB1B/BUBR1, a critical mitotic spindle checkpoint player, as the top-scoring glioblastoma lethal kinase. Knockdown of BUB1B inhibited expansion of BTIC isolates, both in vitro and in vivo, without affecting proliferation of NSCs or astrocytes. Mechanistic studies revealed that BUB1B's GLE2p-binding sequence (GLEBS) domain activity is required to suppress lethal kinetochore–microtubule (KT–MT) attachment defects in glioblastoma isolates and genetically transformed cells with altered sister KT dynamics, which likely favor KT–MT instability. These results indicate that glioblastoma tumors have an added requirement for BUB1B to suppress lethal consequences of altered KT function and further suggest that sister KT measurements may predict cancer-specific sensitivity to BUB1B inhibition and perhaps other mitotic targets that affect KT–MT stability.

Significance: Currently, no effective therapies are available for glioblastoma, the most frequent and aggressive brain tumor. Our results suggest that targeting the GLEBS domain activity of BUB1B may provide a therapeutic window for glioblastoma, as the GLEBS domain is nonessential in untransformed cells. Moreover, the results further suggest that sister KT distances at metaphase may predict sensitivity to anticancer therapeutics targeting KT function. Cancer Discov; 3(2); 198–211. ©2012 AACR.

See related commentary by Venere et al., p. 141

This article is highlighted in the In This Issue feature, p. 125
In Recovery from Schizophrenia: Regaining Social Cover – A Phenomenological Investigation
Authors: Schlimme Jann E. , Schwartz Michael A.
Published: November 2012

We offer here a framework for the understanding of being in recovery from schizophrenia as an interpersonal process. We draw upon in-depth phenomenological descriptions of the fundamental changes taking place in an individual’s mental life when they are suffering from schizophrenia. There is a loss of commonsensical habituality and interpersonal capabilities, usually most prominently expressed as an impaired intersubjective resonance. People with schizophrenia cannot as easily automatically and coherently display their own emotion via their facial expressions or perceive those of others, as do ‘normal’ people. This implies that interpersonal resonance between interacting individuals is not automatic, as is often taken for granted. The need to actively rebuild interpersonal resonance also holds true for the interacting ‘normal’ person, but would be an unfamiliar and unexpected task. These difficulties in empathizing provoke a mismatch in interpersonal resonance, often leading to the intuition that the person having schizophrenia lacks (explicit) self-awareness. We conclude that there is a mismatch in the form and scope of the social cover extended to the social role opportunities available in trans-Atlantic cultural settings for people with schizophrenia. Typically, these social roles imply that people with schizophrenia are unaware of themselves; however, while they often lack insight or may not consider their symptoms as signs of a mental disorder, they are usually not ‘confused’ or ‘distracted’ in the sense of no longer being aware of themselves. We discuss various options for adequate social cover achievable for people with schizophrenia, demonstrating their impact on the recovery process.