Choice Of Placement Research Articles

ACHESYM: standardized placement of macromolecular models in the unit cell

Unique choice of the unit cell and the asymmetric unit are well defined and described in the International Tables for Crystallography vol. A. Unfortunately, the placement of molecules within the unit cell is not standardized. Since structure solution programs often use random numbers in their algorithms, the selected set of atomic coordinates may be different even with successive runs of the same program. Although formally correct, an arbitrary choice of molecular placement within the unit cell is confusing and may lead to interpretation errors [1]. With the use of the anti-Cheshire unit cell introduced by Dauter [2], for all space groups without inversion symmetry, it is possible to transform the molecular model such that its center of gravity falls within the anti-Cheshire asymmetric unit cell. It means that for macromolecular crystal structures it should be possible to standardize the placement of the molecules within the unit cell. In consequence, it should be easier for crystallographers and non-crystallographers to compare similar or related crystal structures. An implementation of the anti-Cheshire concept has been programmed in Python as a web service, aCHESYM. The aCHESYM program takes a PDB file as input and transforms the macromolecular model into the desired anti-Cheshire region. The program can also handle structure factor CIF files if the transformation used requires reindexing of the reflection data. The unit cell, coordinates and displacement parameters of all atoms after transformation are saved in a new PDB file. All the calculated transformations are reversible, so there is no danger of data loss. Moreover, the program helps the user to find the most compact assembly of the molecules (chains) in the structure when there are several chains in the asymmetric unit.

Preoperative Assessment of Chest Wall Invasion in Non-Small Cell Lung Cancer Using Surgeon-Performed Ultrasound

Chest wall invasion in operable lung cancer upgrades the stage and can affect operative planning. Diagnosing chest wall invasion preoperatively is important in patient consent, in the choice of operative incision placement, and can be helpful in choosing an operative approach (open vs thoracoscopic). The objectives of this study were to determine the diagnostic accuracy of preoperative, surgeon-performed ultrasound (US) in assessing tumoral chest wall invasion (T3) in non-small cell lung cancer (NSCLC) patients and to compare its accuracy vs preoperative computed tomography (CT). This study was a prospective clinical trial (ClinicalTrials.gov: NCT01206894) that prospectively enrolled patients between September 2010 and January 2013. Eligible patients included those with NSCLC abutting the parietal pleura or invading the chest wall on preoperative CT scan of the chest and who were planned for surgical resection. Criteria for chest wall invasion on US included (1) disruption of the parietal pleura, (2) invasion of the ribs, or (3) impairment of pleural movement with respiration. The US chest wall examination was performed by the thoracic surgical team immediately before the surgical intervention. Sensitivity and specificity for CT scan and US in assessing chest wall invasion were calculated using definitive chest wall invasion on final pathologic analysis as the gold standard for chest wall invasion. During a 28-month period, 28 patients (15 men and 13 women) patients were prospectively enrolled. Mean age was 62 ± 11 years, and mean body mass index was 25.3 ± 4.5 kg/m(2). The average time for surgeon-performed US assessment looking for chest wall invasion was 5.3 ± 5 minutes. The sensitivity of US in evaluating chest wall invasion was 90.9% and the specificity was 85.7%. CT scan was associated with a sensitivity of 61.5% and a specificity of 84.6%. The positive and negative predictive values of surgeon-performed US for tumoral chest wall invasion were 83.3% and 92.3%, respectively, compared with 80% and 68.8% for CT scan. Surgeon-performed preoperative chest wall US can reliably diagnose tumoral chest wall invasion in patients with NSCLC. CT scan has poor sensitivity in predicting chest wall invasion preoperatively. Surgeon-performed US can be considered as a complementary adjunct to preoperative imaging in patients with pulmonary lesions abutting the chest wall to improve preoperative diagnosis, staging, and operative planning.

Encircled in water: Modelling watercourses of the late Neolithic – early Copper Age Vinča culture sites in the Danube region (c. 5300 – 4500 BC)

Abstract This paper presents a GIS model of the watercourses and settlement locations in the Danube region around Belgrade during the course of late Neolithic Vinca culture (late 6th and early 5th Millennium BC). Vinca culture settlements and material culture characteristic of the central Balkans and parts of Vojvodina and Transylvania grew up around major waterways like Danube, Sava, Morava, Tisza and Timis rivers. The lack of research based on incorporation of landscape studies, water dynamics, paleoenvironment characteristics, and settlement location patterns has hindered our knowledge on the decision making of the late Neolithic population when choosing where to settle. Using computer models of the terrain, satellite image overlays and flood modelling, the decisions underlying the location of Vinca settlement sites in the area around present day Belgrade are analysed. The model will show that the choice of settlement placement in regard to water accessibility was not left to chance, but rather a deliberate decision was needed to ensure survival in an inhospitable, often flooded region of Vojvodina.

Peut-on expliquer l’acquisition de l’alternance de l’adjectif en français à partir de l’input ?

This article proposes to study the acquisition of the placement of attributive adjectives by French-speaking children between the ages of 3;9 and 4;6. It examines the possibility to account for children’s uses and evolution on the basis of the model provided by the input, considering that there is a mismatch between speakers’ abstract knowledge of alternation and their behaviour in usage. The study consists of a comparison between the productions of three children at two points in their development, and the uses of their interlocutors, in situations of games. Results show that alternation appears late and develops slowly in children’s productions, suggesting a very long process of acquisition. They also indicate that children heavily rely on the input in their choices of placement, which influences how they come to master alternation. This supports a usage-based approach to the acquisition of word order and of the Adjective category.

Method Based on Multi-Attribute Decision Making of Receiving-End Power Grid DC Location Selection

For Receiving-end AC system, DC location selection depends on its role in supporting the DC system and economy. This paper proposes a method based on multi-attribute decision making of receiving-end power grid DC location selection. First, the balance of power DC location selected by region; then select the optimal placement through multi-attribute decision making; finally checked by calculating the feasibility of the selected placement. Zha Lute DC Shandong receiving-end power grid placement choice proved the effectiveness of the proposed method.

Plasticity in Nest Placement of the Turtle Dove (Streptopelia Turtur): Experimental Evidence from Moroccan Agro-ecosystems

A total of 364 Turtle Dove ( Streptopelia turtur) nests were found in the Tadla irrigated area during the 2006–2009 breeding seasons. Of these, 135 were located in orange orchards, 178 in olive orchards and 51 in olive hedgerows. Gaussian generalised linear modelling was used to model the nest height and the nest–trunk distance according to the characteristics of olive and orange trees in the orchards and hedgerows. Tree height and type of plantings had the strongest effects on both nest height ( R2 = 0.67) and nest–trunk distance ( R2 = 0.48). Overall, the same pattern of Turtle Dove nest height was recorded in the three types of plantings, whereas different patterns were noted for the nest–trunk distance. The results provide evidence of non-random patterns of nest placement in olive and orange agro-ecosystems. This game species exhibits adaptive behavioural plasticity in nest placement and appears to be well-adapted to the olive and orange grove conditions in this region. This high adaptability is beneficial to maintaining the species in these artificial habitats. Additional quantitative studies are needed to improve our understanding on the mechanisms driving the choice of nest placement by Turtle Doves in this agricultural man-made environment.

Analyzing Body Movements within the Laban Effort Framework Using a Single Accelerometer

This article presents a study on analyzing body movements by using a single accelerometer sensor. The investigated categories of body movements belong to the Laban Effort Framework: Strong—Light, Free—Bound and Sudden—Sustained. All body movements were represented by a set of activities used for data collection. The calculated accuracy of detecting the body movements was based on collecting data from a single wireless tri-axial accelerometer sensor. Ten healthy subjects collected data from three body locations (chest, wrist and thigh) simultaneously in order to analyze the locations comparatively. The data was then processed and analyzed using Machine Learning techniques. The wrist placement was found to be the best single location to record data for detecting Strong—Light body movements using the Random Forest classifier. The wrist placement was also the best location for classifying Bound—Free body movements using the SVM classifier. However, the data collected from the chest placement yielded the best results for detecting Sudden—Sustained body movements using the Random Forest classifier. The study shows that the choice of the accelerometer placement should depend on the targeted type of movement. In addition, the choice of the classifier when processing data should also depend on the chosen location and the target movement.

Randomizing task placement and route selection do not randomize traffic (enough)

Dragonflies are one of the most promising topologies for the Exascale effort for their scalability and cost. Dragonflies achieve very high throughput under uniform traffic, but have a pathological behavior under other regular traffic patterns, some of them very common in HPC applications, such as the multi-dimensional stencil communication pattern or certain permutation patterns. A recent study showed that randomization of task placement greatly improves the performance of these pathological traffic patterns by increasing the similarity of the load they induce to a uniformly distributed load. In this work we provide a theoretical model that is able to predict the expected performance of a generic dragonfly network under uniform traffic and characterize performance-optimal, minimal cost dragonflies. We then match the predictions of this model with the performance obtained through the detailed simulation of a wide range of dragonfly configurations. In these same scenarios, we explore the performance of other non-uniform traffic patterns and investigate the impact of randomization techniques based on both task placement and indirect routing. For these previously unexplored traffic patterns, we obtain similar results to those obtained in previous works for the multi-dimensional stencil communication pattern: randomizing task placement and/or path choice is effective in improving the performance of pathological workloads. However, we also show that neither uniformization technique is able to close the gap between the performance of these traffic patterns and the ideal performance of uniform random traffic, leaving significant room for improvement (best achieved performance is only roughly $$50~\%$$50% of uniform performance).

Computed tomography-based classification of axis vertebra: choice of screw placement

The purpose of the study was to: (1) introduce a new CT-based parameter: free facet area and provide its normative data; (2) standardize the method of measuring isthmus width and height of the axis vertebra; (3) propose a new grading system to predict the difficulty in inserting transarticular and C2 pedicle screws. Spiral CT scans of 47 adult dry axis vertebrae were studied. The methods of measuring isthmus width, isthmus height and free facet area are described. The mean isthmus width was 5.04mm on the right side and 5.42mm on the left side. The mean isthmus height was 5.21mm on the right side and 5.45mm on the left side. Mean free facet area was 61.23% on the right side and 70.18% on the left side. A novel grading system is proposed on the basis of these three parameters. As per this grading system, 40.4% of the sides were found to be difficult for transarticular and 24.5% sides for C2 pedicle screw insertion (total score 2, 3, 4). A Management protocol is suggested on the basis of the grading system. Inserting a transarticular screw was more frequently difficult as compared to pedicle screw. A new CT-based parameter (free facet area) and an efficient grading have been proposed to help surgeons choose the appropriate screw options, appreciate the complex anatomy of this region and compare data across various studies.

Hemodialysis catheter malposition: How to prevent this fault?

Cannulation of central veins and placement of catheters for temporary hemodialysis is a common procedure in the management of patients with end stage renal failure. The right internal jugular vein is the site of choice for central venous catheter placement, because it provides a more direct route into the right atrium and therefore helps prevent sheath kinking and further catheter secondary shift, being associated with the lowest complication rate. The procedure can be associated with a variety of malpositions of the catheter and rarely, can lead to significant morbidity and even mortality, if this is not recognized and not corrected early [1]. Non-tunneled percutaneous central vein catheter is usually placed at the bedside, while tunneled catheters can be placed in an interventional suite or operating room using fluoroscopic guidance.

Summary of: Dental composite materials and renal function in children

To examine whether greater exposure to resin-based composite materials, which may intra-orally release bisphenol A (BPA), is associated with worse renal function outcomes in children. Prospective multi-centre study. Community health dental clinics in Boston and Maine from 1997-2005. Five hundred and thirty-four New England Children's Amalgam Trial participants aged six to ten years were randomised to treatment with amalgam or resin-based composite restorations over five years of follow-up. Restorations were placed according to treatment arm, and sealants placed per standard of care. Cumulative composite exposure was calculated using surface-years (each treated surface weighted by number years present). Urinary excretion of albumin, gamma-glutamyl transpeptidase (gamma-GT), and N-acetyl-β-D-glucosaminidase (NAG) were available for 417 children. Analysis of covariance showed no association between exposure to dental composites, polyacid-modified compomer, or flowable composite dental sealants and preventative resin restorations with levels of renal function. There was no association between composite materials and thresholds indicating renal damage in logistic regression models. This study found no harmful associations between dental composite materials and renal function in children. Therefore, concerns about renal function need not be a consideration in the choice of dental restoration material or placement of preventative dental sealants.

Dental composite materials and renal function in children

To examine whether greater exposure to resin-based composite materials, which may intra-orally release bisphenol A (BPA), is associated with worse renal function outcomes in children. Prospective multi-centre study. Community health dental clinics in Boston and Maine from 1997-2005.Subjects and methods Five hundred and thirty-four New England Children's Amalgam Trial participants aged six to ten years were randomised to treatment with amalgam or resin-based composite restorations over five years of follow-up. Restorations were placed according to treatment arm, and sealants placed per standard of care. Cumulative composite exposure was calculated using surface-years (each treated surface weighted by number years present). Urinary excretion of albumin, gamma-glutamyl transpeptidase (gamma-GT), and N-acetyl-β-D-glucosaminidase (NAG) were available for 417 children. Analysis of covariance showed no association between exposure to dental composites, polyacid-modified compomer, or flowable composite dental sealants and preventative resin restorations with levels of renal function. There was no association between composite materials and thresholds indicating renal damage in logistic regression models. This study found no harmful associations between dental composite materials and renal function in children. Therefore, concerns about renal function need not be a consideration in the choice of dental restoration material or placement of preventative dental sealants.

Low-dose intrathecal fluorescein and etiology-based graft choice in endoscopic endonasal closure of CSF leaks

ObjectiveSkull base cerebrospinal fluid (CSF) leaks of various etiologies are increasingly repaired through the natural corridor using an endoscopic endonasal approach. Characteristics of the skull base defect significantly correlate with etiology, which should be ascertained to guide surgical management. The objectives of this study were to assess the long-term outcomes of patients that underwent endoscopic endonasal repair of CSF leak using low-dose intrathecal fluorescein (ITF) and an etiology-based algorithm for multi-layer graft closure. MethodsPatients were divided into 4 groups: A – congenital, B – post-traumatic, C – post-endonasal surgery, D – post-craniotomy. Low-dose ITF was utilized in all case series. Long-term clinical follow-up data, including perioperative complications associated with the use of intrathecal fluorescein and leak closure rates, were obtained retrospectively. Endoscopic visualization of fluorescein-stained CSF as well as the method of skull base closure and graft material is detailed. ResultsWe identified a total of 41 patients (N=24 in Group A, N=4 in Group B, N=12 in Group C and N=1 in Group D) that underwent 50 CSF leak repairs using the endoscopic endonasal approach with an average follow-up of 31.6 months. Nine patients (21.9%) had undergone a previous attempt at CSF leak repair. Lumbar drain was used intraoperatively in 26 patients (63.4%) and kept in place for an average duration of 3.25 days. ITF successfully identified the site of leak in 80.5% of cases regardless of etiology. Leaks were successfully closed in 92% of patients. One patient (2.4%) experienced transient leg weakness following lumbar drain placement. Another patient (2.4%) developed hydrocephalus requiring a ventriculoperitoneal shunt. ConclusionLow-dose ITF is a safe and useful adjunct to endoscopic endonasal repair of CSF leaks with minimal complications and successful localization of the leak in approximately 80%. An etiology-based approach to graft choice and duration of lumbar drain placement in CSF leak repair may optimize closure rates.

Issues in or with Genesis 22: An overview of exegetical issues related to one of the most problematic biblical chapters

The understanding of the Akedah (Genesis 22) has since its very inception been contentious. The psychologically disturbing and theologically challenging account renders a series of exegetical and interpretative problems. Often methodology serves to hinder a fuller perception of the elements and aspects of the text, examples of which are given here relating to the opening phrase to the chapter, the choice of literary or historical placement implied by the exegete�s choices on the opening phrase, the treatment of verses 15 to 18 (and, hence, verse 1) and the treatment of the morality (ethics and philosophy) involved with this text.

Different Surveys, Different Results? A Comparison of Two Surveys on the 2009 European Parliamentary Election

The European Election Survey (EES) is carried out in all member states at the time of each European Parliament election. The mode of data collection (mainly telephone interviews) and the sampling procedure (achieving 1,000 interviews in each country) raise doubts about the data quality. Until now knowledge has been lacking about the extent to which the mode of data collection and the sampling procedure bias the results. In one European country an independently designed election survey is carried out: The Swedish National European Parliament Election Study (SNES). The survey consists of face-to-face interviews of a random net sample of 2,682 individuals (response rate 67 per cent compared to 11.2 in the Swedish EES survey). In addition, SNES includes a large number of variables from official register data (including validated voting) that facilitates analyses without any non-responses generating missing data. This quasi-experimental methodological set up is used to compare the data from the two surveys for voter turnout, left–right placement and party choice. Results show that EES overestimates turnout levels more than SNES. EES also has a large overrepresentation of highly educated respondents, and thus underestimates differences in turnout between highly and less educated citizens. As for left–right placement, respondents in EES place both themselves and the parties on more extreme positions. Regarding party choice, the main difference between the surveys is that the EES largely underestimates the share of Social Democratic voters.

Birth Parents’ Portrayals in Children’s Adoption Literature

Few studies have systematically analyzed adoption-themed books for children or how birth parents are depicted. This article analyzes 104 books in English designated for children aged 4 to 8 years that are focused on adoption to understand how birth parents are portrayed. Findings indicate that birth parents are often represented with stereotypical, value-based, and cultural perceptions, resulting in an inability to care for children as the reasons or choices for adoption placement. As parents rely on books to develop narratives and to socialize children, the lack of accurate depictions of birth parents and the structural barriers they face has implications for adoptee understanding of adoption and for adoptee adjustment and identity.

Hint-Based Execution of Workloads in Clouds with Nefeli

Infrastructure-as-a-Service clouds offer entire virtual infrastructures for distributed processing while concealing all physical underlying machinery. Current cloud interface abstractions restrict users from providing information regarding usage patterns of their requested virtual machines (VMs). In this paper, we propose Nefeli, a virtual infrastructure gateway that lifts this restriction. Through Nefeli, cloud consumers provide deployment hints on the possible mapping of VMs to physical nodes. Such hints include the collocation and anticollocation of VMs, the existence of potential performance bottlenecks, the presence of underlying hardware features (e.g., high availability), the proximity of certain VMs to data repositories, or any other information that would contribute in a more effective placement of VMs to physical hosting nodes. Consumers designate only properties of their virtual infrastructure and remain at all times agnostic to the cloud internal physical characteristics. The set of consumer-provided hints is augmented with high-level placement policies specified by the cloud administration. Placement policies and hints form a constraint satisfaction problem that when solved, yields the final VM-to-host placement. As workloads executed by the cloud may change over time, VM-to-host mappings must follow suit. To this end, Nefeli captures such events, changes VM deployment, helps avoid bottlenecks, and ultimately, improves the quality of the rendered services. Using our prototype, we examine overheads involved and show significant improvements in terms of time needed to execute scientific and real application workloads. We also demonstrate how power-aware policies may reduce the energy consumption of the physical installation. Finally, we compare Nefeli's placement choices with those attained by the open-source cloud middleware, OpenNebula.

A new perspective for efficient virtual-cache coherence

Coherent shared virtual memory (cSVM) is highly coveted for heterogeneous architectures as it will simplify programming across different cores and manycore accelerators. In this context, virtual L1 caches can be used to great advantage, e.g., saving energy consumption by eliminating address translation for hits. Unfortunately, multicore virtual-cache coherence is complex and costly because it requires reverse translation for any coherence request directed towards a virtual L1. The reason is the ambiguity of the virtual address due to the possibility of synonyms. In this paper, we take a radically different approach than all prior work which is focused on reverse translation. We examine the problem from the perspective of the coherence protocol. We show that if a coherence protocol adheres to certain conditions, it operates effortlessly with virtual caches, without requiring reverse translations even in the presence of synonyms. We show that these conditions hold in a new class of simple and efficient request-response protocols that use both self-invalidation and self-downgrade. This results in a new solution for virtual-cache coherence, significantly less complex and more efficient than prior proposals. We study design choices for TLB placement under our proposal and compare them against those under a directory-MESI protocol. Our approach allows for choices that are particularly effective as for example combining all per-core TLBs in a single logical TLB in front of the last level cache. Significant area, energy, and performance benefits ensue as a result of simplifying the entire multicore memory organization.

Assessing the efficiency of different CSO positions based on network graph characteristics

The technical design of urban drainage systems comprises two major aspects: first, the spatial layout of the sewer system and second, the pipe-sizing process. Usually, engineers determine the spatial layout of the sewer network manually, taking into account physical features and future planning scenarios. Before the pipe-sizing process starts, it is important to determine locations of possible weirs and combined sewer overflows (CSOs) based on, e.g. distance to receiving water bodies or to a wastewater treatment plant and available space for storage units. However, positions of CSOs are also determined by topological characteristics of the sewer networks. In order to better understand the impact of placement choices for CSOs and storage units in new systems, this work aims to determine case unspecific, general rules. Therefore, based on numerous, stochastically generated virtual alpine sewer systems of different sizes it is investigated how choices for placement of CSOs and storage units have an impact on the pipe-sizing process (hence, also on investment costs) and on technical performance (CSO efficiency and flooding). To describe the impact of the topological positions of these elements in the sewer networks, graph characteristics are used. With an evaluation of 2,000 different alpine combined sewer systems, it was found that, as expected, with CSOs at more downstream positions in the network, greater construction costs and better performance regarding CSO efficiency result. At a specific point (i.e. topological network position), no significant difference (further increase) in construction costs can be identified. Contrarily, the flooding efficiency increases with more upstream positions of the CSOs. Therefore, CSO and flooding efficiency are in a trade-off conflict and a compromise is required.

Mapping the Join Calculus to Heterogeneous Hardware

As modern architectures introduce additional heterogeneity and parallelism, we look for ways to deal with this that do not involve specialising software to every platform. In this paper, we take the Join Calculus, an elegant model for concurrent computation, and show how it can be mapped to an architecture by a Cartesian-product-style construction, thereby making use of the calculus' inherent non-determinism to encode placement choices. This unifies the concepts of placement and scheduling into a single task.