bluuebunny/crossref_metadata_2025 huggingface dataset:
The Direct-to-Data (D2D) cache
Authors: Sembrant Andreas , Hagersten Erik , Black-Schaffer David
Published: October 2014

Modern processors optimize for cache energy and performance by employing multiple levels of caching that address bandwidth, low-latency and high-capacity. A request typically traverses the cache hierarchy, level by level, until the data is found, thereby wasting time and energy in each level. In this paper, we present the Direct-to-Data (D2D) cache that locates data across the entire cache hierarchy with a single lookup. To navigate the cache hierarchy, D2D extends the TLB with per cache-line location information that indicates in which cache and way the cache line is located. This allows the D2D cache to: 1) skip levels in the hierarchy (by accessing the right cache level directly), 2) eliminate extra data array reads (by reading the right way directly), 3) avoid tag comparisons (by eliminating the tag arrays), and 4) go directly to DRAM on cache misses (by checking the TLB). This reduces the L2 latency by 40% and saves 5-17% of the total cache hierarchy energ

D2D's lower L2 latency directly improves L2 sensitive applications' performance by 5-14%. More significantly, we can take advantage of the L2 latency reduction to optimize other parts of the micro-architecture. For example, we can reduce the ROB size for the L2 bound applications by 25%, or we can reduce the L1 cache size, delivering an overall 21% energy savings across all benchmarks, without hurting performance.
SC2
Authors: Arelakis Angelos , Stenstrom Per
Published: October 2014

Low utilization of on-chip cache capacity limits performance and wastes energy because of the long latency, limited bandwidth, and energy consumption associated with off-chip memory accesses. Value replication is an important source of low capacity utilization. While prior cache compression techniques manage to code frequent values densely, they trade off a high compression ratio for low decompression latency, thus missing opportunities to utilize capacity more effectively.

This paper presents, for the first time, a detailed designspace exploration of caches that utilize statistical compression. We show that more aggressive approaches like Huffman coding, which have been neglected in the past due to the high processing overhead for (de)compression, are suitable techniques for caches and memory. Based on our key observation that value locality varies little over time and across applications, we first demonstrate that the overhead of statistics acquisition for code generation is low because new encodings are needed rarely, making it possible to off-load it to software routines. We then show that the high compression ratio obtained by Huffman-coding makes it possible to utilize the performance benefits of 4X larger last-level caches with about 50% lower power consumption than such larger caches
Single-graph multiple flows
Authors: Voitsechov Dani , Etsion Yoav
Published: October 2014

We present the single-graph multiple-flows (SGMF) architecture that combines coarse-grain reconfigurable computing with dynamic dataflow to deliver massive thread-level parallelism. The CUDA-compatible SGMF architecture is positioned as an energy efficient design alternative for GPGPUs.

The architecture maps a compute kernel, represented as a dataflow graph, onto a coarse-grain reconfigurable fabric composed of a grid of interconnected functional units. Each unit dynamically schedules instances of the same static instruction originating from different CUDA threads. The dynamically scheduled functional units enable streaming the data of multiple threads (or graph flows, in SGMF parlance) through the grid. The combination of statically mapped instructions and direct communication between functional units obviate the need for a full instruction pipeline and a centralized register file, whose energy overheads burden GPGPU

We show that the SGMF architecture delivers performance comparable to that of contemporary GPGPUs while consuming 57% less energy on average.
An examination of the architecture and system-level tradeoffs of employing steep slope devices in 3D CMPs
Authors: Swaminathan Karthik , Liu Huichu , Sampson Jack , Narayanan Vijaykrishnan
Published: October 2014

For any given application, there is an optimal throughput point in the space of per-processor performance and the number of such processors given to that application. However, due to thermal, yield, and other constraints, not all of these optimal points can plausibly be constructed with a given technology. In this paper, we look at how emerging steep slope devices, 3D circuit integration, and trends in process technology scaling will combine to shift the boundaries of both attainable performance, and the optimal set of technologies to employ to achieve it. We propose a heterogeneous-technology 3D architecture capable of operating efficiently at an expanded number of points in this larger design space and devise a heterogeneity and thermal aware scheduling algorithm to exploit its potential. Our heterogeneous mapping techniques are capable of producing speedups ranging from 17% for a high end server workloads running at around 90°C to over 160% for embedded systems running below 60°C
STAG
Authors: Venkatesan Rangharajan , Ramasubramanian Shankar Ganesh , Venkataramani Swagath , Roy Kaushik , Raghunathan Anand
Published: October 2014

General-purpose Graphics Processing Units (GPGPUs) are widely used for executing massively parallel workloads from various application domains. Feeding data to the hundreds to thousands of cores that current GPGPUs integrate places great demands on the memory hierarchy, fueling an ever-increasing demand for on-chip memory.

In this work, we propose STAG, a high density, energy-efficient GPGPU cache hierarchy design using a new spintronic memory technology called Domain Wall Memory (DWM). DWMs inherently offer unprecedented benefits in density by storing multiple bits in the domains of a ferromagnetic nanowire, which logically resembles a bit-serial tape. However, this structure also leads to a unique challenge that the bits must be sequentially accessed by performing "shift" operations, resulting in variable and potentially higher access latencies. To address this challenge, STAG utilizes a number of architectural techniques : (i) a hybrid cache organization that employs different DWM bit-cells to realize the different memory arrays within the GPGPU cache hierarchy, (ii) a clustered, bit-interleaved organization, in which the bits in a cache block are spread across a cluster of DWM tapes, allowing parallel access, (iii) tape head management policies that predictively configure DWM arrays to reduce the expected number of shift operations for subsequent accesses, and (iv) a shift aware pro- motion buffer (SaPB), in which accesses to the DWM cache are predicted based on intra-warp locality, and locations that would incur a large shift penalty are promoted to a smaller buffer. Over a wide range of benchmarks from the Rodinia, IS- PASS and Parboil suites, STAG achieves significant benefits in performance (12.1% over SRAM and 5.8% over STT-MRAM) and energy (3.3X over SRAM and 2.6X over STT-MRAM)
Towards energy proportionality for large-scale latency-critical workloads
Authors: Lo David , Cheng Liqun , Govindaraju Rama , Barroso Luiz André , Kozyrakis Christos
Published: October 2014

Reducing the energy footprint of warehouse-scale computer (WSC) systems is key to their affordability, yet difficult to achieve in practice. The lack of energy proportionality of typical WSC hardware and the fact that important workloads (such as search) require all servers to remain up regardless of traffic intensity renders existing power management techniques ineffective at reducing WSC energy use.

We present PEGASUS, a feedback-based controller that significantly improves the energy proportionality of WSC systems, as demonstrated by a real implementation in a Google search cluster. PEGASUS uses request latency statistics to dynamically adjust server power management limits in a fine-grain manner, running each server just fast enough to meet global service-level latency objectives. In large cluster experiments, PEGASUS reduces power consumption by up to 20%. We also estimate that a distributed version of PEGASUS can nearly double these savings
Optimizing virtual machine consolidation performance on NUMA server architecture for cloud workloads
Authors: Liu Ming , Li Tao
Published: October 2014

Server virtualization and workload consolidation enable multiple workloads to share a single physical server, resulting in significant energy savings and utilization improvements. The shift of physical server architectures to NUMA and the increasing popularity of scale-out cloud applications undermine workload consolidation efficiency and result in overall system degradation. In this work, we characterize the consolidation of cloud workloads on NUMA virtualized systems, estimate four different sources of architecture overhead, and explore optimization opportunities beyond the default NUMA-aware hypervisor memory management

Motivated by the observed architectural impact on cloud workload consolidation performance, we propose three optimization techniques incorporating NUMA access overhead into the hypervisor's virtual machine memory allocation and page fault handling routines. Among these, estimation of the memory zone access overhead serves as a foundation for the other two techniques: a NUMA overhead aware buddy allocator and a P2M swap FIFO. Cache hit rate, cycle loss due to cache miss, and IPC serve as indicators to estimate the access cost of each memory node. Our optimized buddy allocator dynamically selects low-overhead memory zones and "proportionally" distributes memory pages across target nodes. The P2M swap FIFO records recently unused PFN, MFN lists for mapping exchanges to rebalance memory access pressure within one domain. Our real system based evaluations show a 41.1% performance improvement when consolidating 16-VMs on a 4- socket server (the proposed allocator contributes 22.8% of the performance gain and the P2M swap FIFO accounts for the rest). Furthermore, our techniques can cooperate well with other methods (i.e. vCPU migration) and scale well when varying VM memory size and the number of sockets in a physical host
Flipping bits in memory without accessing them
Authors: Kim Yoongu , Daly Ross , Kim Jeremie , Fallin Chris , Lee Ji Hye , Lee Donghyuk , Wilkerson Chris , Lai Konrad , Mutlu Onur
Published: October 2014

Memory isolation is a key property of a reliable and secure computing system--an access to one memory address should not have unintended side effects on data stored in other addresses. However, as DRAM process technology scales down to smaller dimensions, it becomes more difficult to prevent DRAM cells from electrically interacting with each other. In this paper, we expose the vulnerability of commodity DRAM chips to disturbance errors. By reading from the same address in DRAM, we show that it is possible to corrupt data in nearby addresses. More specifically, activating the same row in DRAM corrupts data in nearby rows. We demonstrate this phenomenon on Intel and AMD systems using a malicious program that generates many DRAM accesses. We induce errors in most DRAM modules (110 out of 129) from three major DRAM manufacturers. From this we conclude that many deployed systems are likely to be at risk. We identify the root cause of disturbance errors as the repeated toggling of a DRAM row's wordline, which stresses inter-cell coupling effects that accelerate charge leakage from nearby rows. We provide an extensive characterization study of disturbance errors and their behavior using an FPGA-based testing platform. Among our key findings, we show that (i) it takes as few as 139K accesses to induce an error and (ii) up to one in every 1.7K cells is susceptible to errors. After examining various potential ways of addressing the problem, we propose a low-overhead solution to prevent the errors
Architecture implications of pads as a scarce resource
Authors: Zhang Runjie , Wang Ke , Meyer Brett H. , Stan Mircea R. , Skadron Kevin
Published: October 2014

Due to non-ideal technology scaling, delivering a stable supply voltage is increasingly challenging. Furthermore, com- petition for limited chip interface resources (i.e., C4 pads) between power supply and I/O, and the loss of such resources to electromigration, means that constructing a power deliverynetwork (PDN) that satisfies noise margins without compromising performance is and will remain a critical problem for architects and circuit designers alike. Simple guardbanding will no longer work, as the consequent performance penalty will grow with technology scaling

In this paper, we develop a pre-RTL PDN model, VoltSpot, for the purpose of studying the performance and noise tradeoffs among power supply and I/O pad allocation, the effectiveness of noise mitigation techniques, and the consequent implications of electromigration-induced PDN pad failure. Our simulations demonstrate that, despite their integral role in the PDN, power/ground pads can be aggressively reduced (by conversion into I/O pads) to their electromigration limit with minimal performance impact from extra voltage noise - provided the system implements a suitable noise-mitigation strategy. The key observation is that even though reducing power/ground pads significantly increases the number of voltage emergencies, the average noise amplitude increase is small. Overall, we can triple I/O bandwidth while maintaining target lifetimes and incurring only 1.5% slowdown
A low power and reliable charge pump design for phase change memories
Authors: Jiang Lei , Zhao Bo , Yang Jun , Zhang Youtao
Published: October 2014

The emerging Phase Change Memory (PCM) technology exhibits excellent scalability and density potentials. At the same time, they require high current and high voltages to switch cell states. Their working voltages are provided by CMOS-compatible on-chip charge pumps (CPs). Unfortunately, CPs and particularly those for RESET, have a large parasitic power (a dominant component in total power loss) during operations, which significantly degrades their energy efficiency. In addition, CPs seriously suffer from the Time-Dependent Dielectric Breakdown (TDDB) problem due to their boosted operation voltage. To maintain a reasonable lifetime of CPs, existing solutions actively switch them on per-operation basis, resulting in large performance degradation

In this paper, we address the above issues through two designs --- Reset_Sch (RESET scheduling) and CP_Sch (CP scheduling). Reset_Sch schedules when to perform a RESET for different cells upon writing a PCM line. It significantly reduces the power loss, and peak working power of RESET CP. CP_Sch incorporates a fast READ CP design to provide fast charge-up time for reads and minimize performance penalty. Our experimental results show that on average, 70% of power loss for RESET CP can be reduced; and performance loss can be reduced from 16% to 2% while achieving a 16% improvement in reliability
Pacifier
Authors: Qian Xuehai , Sahelices Benjamin , Qian Depei
Published: October 2014

Record and Deterministic Replay (R&R) of multithreaded programs on relaxed-consistency multiprocessors with distributed directory protocol has been a long-standing open problem. The independently developed RelaxReplay [8] solves the problem by assuming write atomicity.

This paper proposes Pacifier, the first R&R scheme to provide a solution without assuming write atomicity. R&R for relaxed-consistency multiprocessors needs to detect, record and replay Sequential Consistency Violations (SCV). Pacifier has two key components: (i) Relog, a general memory reordering logging and replay mechanism that can reproduce SCVs in relaxed memory models, and (ii) Granule, an SCV detection scheme in the record phase with good precision, that indicates whether to record with Relog. We show that Pacifier is a sweet spot in the design space with a reasonable trade-off between hardware and log overhead. An evaluation with simulations mof 16, 32 and 64 processors with Release Consistency (RC) running SPLASH-2 applications indicates that Pacifier incurs 3.9% ~ 16% larger logs. The slowdown of Pacifier during replay is 10.1% ~ 30.5% compared to native execution
CODOMs
Authors: Vilanova Lluïs , Ben-Yehuda Muli , Navarro Nacho , Etsion Yoav , Valero Mateo
Published: October 2014

Today's complex software systems are neither secure nor reliable. The rudimentary software protection primitives provided by current hardware forces systems to run many distrusting software components (e.g., procedures, libraries, plugins, modules) in the same protection domain, or otherwise suffer degraded performance from address space switches.

We present CODOMs (COde-centric memory DOMains), a novel architecture that can provide finer-grained isolation between software components with effectively zero run-time overhead, all at a fraction of the complexity of other approaches. An implementation of CODOMs in a cycle-accurate full-system x86 simulator demonstrates that with the right hardware support, finer-grained protection and run-time performance can peacefully coexist.
Race logic
Authors: Madhavan Advait , Sherwood Timothy , Strukov Dmitri
Published: October 2014

We propose a novel computing approach, dubbed "Race Logic", in which information, instead of being represented as logic levels, as is done in conventional logic, is represented as a timing delay. Under this new information representation, computations can be performed by observing the relative propagation times of signals injected into the circuit (i.e. the outcome of races). Race Logic is especially suited for solving problems related to the
Eliminating redundant fragment shader executions on a mobile GPU via hardware memoization
Authors: Arnau Jose-Maria , Parcerisa Joan-Manuel , Xekalakis Polychronis
Published: October 2014

Redundancy is at the heart of graphical applications. In fact, generating an animation typically involves the succession of extremely similar images. In terms of rendering these images, this behavior translates into the creation of many fragment programs with the exact same input data. We have measured this fragment redundancy for a set of commercial Android applications, and found that more than 40% of the fragments used in a frame have been already computed in a prior frame.

In this paper we try to exploit this redundancy, using fragment memoization. Unfortunately, this is not an easy task as most of the redundancy exists across frames, rendering most HW based schemes unfeasible. We thus first take a step back and try to analyze the temporal locality of the redundant fragments, their complexity, and the number of inputs typically seen in fragment programs. The result of our analysis is a task level memoization scheme, that easily outperforms the current state-of-the-art in low power GPUs

More specifically, our experimental results show that our scheme is able to remove 59.7% of the redundant fragment computations on average. This materializes to a significant speedup of 17.6% on average, while also improving the overall energy efficiency by 8.9% on average.
Monastic and Church Archaeology
Authors: Gilchrist Roberta
Published: October 2014

Major advances in church and monastic archaeology are discussed in terms of two distinct waves, ca. 1970–1995 and 1995 to the time of writing (2014). The first wave was influenced by landscape history and processual archaeology; scholarship focused principally on historical, economic, and technological questions and targeted individual sites and monuments for study. The second wave has been informed by postprocessual approaches and considers change and complexity in religious landscapes and perspectives on religious space, embodiment, and agency. In conclusion, this article calls for a more holistic approach to the archaeology of medieval Christian belief, one which moves beyond the focus on institutions and monuments that has characterized monastic and church archaeology and extends archaeological study to include the performative rituals of Christian life and death in the Middle Ages.
Ethnographies of Encounter
Authors: Faier Lieba , Rofel Lisa
Published: October 2014

Ethnographies of encounter are one response to calls to decolonize anthropology. These ethnographies explore how culture making occurs through unequal relationships involving two or more groups of people and things that appear to exist in culturally distinct worlds. The term encounter refers to everyday engagements across difference. Ethnographies of encounter focus on the cross-cultural and relational dynamics of these processes. They consider how such engagements bring discrepant stakes and histories together in ways that produce new cultural meanings, categories, objects, and identities. This article examines a transection of the discipline that shares this methodology. We focus on encounter approaches to (a) transnational capitalism, (b) space and place, and (c) human-nonhuman relations. Rather than taking capitalism, space and place, and humanness as contextual frameworks, these ethnographies demonstrate how encounter is the means by which these categories emerge.
Primate Taxonomy: Inflation or Real?
Authors: Groves Colin P.
Published: October 2014

This article reviews changes in primate taxonomy, especially those pertaining to the meaning of the term species, since its inception two and a half centuries ago. Despite continuing discoveries and the involvement of competent practitioners, the adoption of the polytypic species concept, especially underpinned by the biological species concept, ensured that primate taxonomy was in a sorry state by the middle of the twentieth century. In the latter half of the twentieth century, a gradual rethinking of the nature of species took place, and many different species concepts were proposed. The phylogenetic species concept has been widely adopted over the past ∼20 years, sustained by a gradual realization that species are evolutionary lineages. This review provides examples of how the old way of thinking about species hampered our understanding of primate biodiversity and of how the phylogenetic species concept (or the diagnosability criterion under the general lineage concept) has clarified matters, opening them up for discussion. The adoption of this evolutionary view of species has implications for conservation, particularly because it increases recognition of biodiversity.
Ethnoveterinary Study of Medicinal Plants in a Tribal Society of Sulaiman Range
Authors: Tariq Akash , Mussarat Sakina , Adnan Muhammad , AbdElsalam Naser M. , Ullah Riaz , Khan Abdul Latif
Published: October 2014

The aims of the present study were (i) to document ethnoveterinary plants and their formulation techniques in an unexplored region of Pakistan and (ii) to select candidate medicinal plants with high consensus factor and fidelity value for furtherin vitroinvestigation. A total of 60 informants were interviewed using semistructured questionnaire. A total of 41 plants belonging to 30 families were used to treat livestock ailments in study area. Mostly leaves (47%) were used in recipes formulation mostly in the form of decoction. Gastrointestinal infections were found more common and majority of the plants were used against cow (31) and buffaloes (24) ailments. Recovery time of majority of the recipes was three to four days. Informant consensus factor (Fic) results have shown a high degree of consensus for gastrointestinal, respiratory, and reproductive (0.95 each) ailments. Fidelity level (FL) results showed thatAsparagus gracilisranked first with FL value 93% followed byRumex hastatusranked second (91%) andTinospora cordifoliaranked third (90%). Aged farmers and nomads had more traditional knowledge as compared to younger ones. Plants with high Fic and FL values could be further investigatedin vitrofor the search of some novel bioactive compounds and young generation should be educated regarding ethnoveterinary practices.
Nonlinear Current Control for Reluctance Actuator with Hysteresis Compensation
Authors: Liu Yu-Ping , Liu Kang-Zhi , Yang Xiaofeng
Published: October 2014

The next-generation fine stage of the wafer scanner needs a suitable actuator to meet the requirements of high speed, high acceleration, and high precision. The voice coil actuator is no longer the best choice because of its large size and the heat dissipation is difficult to solve. The reluctance actuator can provide a big force based on a unique property of small volume and low current, making it a very suitable candidate. But the strong nonlinearity such as the hysteresis between the current and force limits the reluctance actuator applications in nanometer positioning. This paper proposes a nonlinear current control configuration with hysteresis compensation using the adaptive multilayer neural network. Simulation results show that the hysteresis compensator is effective in overcoming the hysteresis and is promising in precision control applications.
Seasonality of Water Chemistry, Carbonate Production, and Biometric Features of Two Species ofCharain a Shallow Clear Water Lake
Authors: Pukacz Andrzej , Pełechaty Mariusz , Frankowski Marcin , Kowalski Artur , Zwijacz-Koszałka Kinga
Published: October 2014

The objective of this study was to analyze the temporal variability of biometric features and the carbonate production of two charophytes:Chara polyacanthaA. Braun andChara rudisA. Braun against the background of the physical-chemical properties of water. The investigation was carried out in a small, mid-forest Lake Jasne (western Poland). It is a polymictic, mesotrophic, hardwater ecosystem dominated by charophyte vegetation. Each month, 10 individuals of each species were characterized in terms of morphometric features, fresh and dry weight, and the percentage of calcium carbonate. Additionally, physical-chemical parameters of the water were studied. The results of physical-chemical analyses indicated similar habitat conditions for both species. Despite smaller dry weightC. polyacanthawas characterized by greater morphological variability and higher rates of growth and percentage share of calcium carbonate in dry mass thanC. rudis. The percentage of calcium carbonates in dry mass did not differ significantly between the species and exceeded 60%, reaching the maximum (76% inC. polyacantha) in July and August. For both species, distinct correlations between the structure of biomass and morphological features were found. The obtained results show the great importance of charophyte vegetation in carbon cycling and functioning of lake ecosystems.
Supply Chain Integration in the Manufacturing Firms in Developing Country: An Ethiopian Case Study
Authors: Georgise Fasika Bete , Thoben Klaus-Dieter , Seifert Marcus
Published: October 2014

With the advancement of information and communication technologies, supply chain integration has been considered a strategic tool for firms to improve their competitiveness. The supply chain integration within processes and between organizations has enhanced value creation. However, the fragmented nature of the business in developing country demonstrates a noticeable difficulty in terms of competitiveness and efficiency. Lack of a relevant literature on practical experience in supply chain integration in developing countries is one of the challenges. The purpose of this research is to identify the level of interorganizational and intraorganizational supply chain integration practices. It also analyzes the challenges faced in the manufacturing firms in developing countries. The methodology followed a thorough review of literature and semistructured interviews amongst the Ethiopian manufacturing industries. The preliminary findings of the study highlight that prevailing approach to supply chain integration is limited to ad hoc functional based boundaries within the firm. The SC integration enablers are also restricted to the traditional way of communications such as telephone, fax, and letters. Firms need to focus on those issues that require attention in pursuance of greater SC integration.
The Role ofHibiscus sabdariffaL. (Roselle) in Maintenance ofEx VivoMurine Bone Marrow-Derived Hematopoietic Stem Cells
Authors: Abdul Hamid Zariyantey , Lin Lin Winnie Hii , Abdalla Basma Jibril , Bee Yuen Ong , Latif Elda Surhaida , Mohamed Jamaludin , Rajab Nor Fadilah , Paik Wah Chow , Wak Harto Muhd Khairul Akmal , Budin Siti Balkis
Published: October 2014

Hematopoietic stem cells- (HSCs-) based therapy requiresex vivoexpansion of HSCs prior to therapeutic use. However,ex vivoculture was reported to promote excessive production of reactive oxygen species (ROS), exposing HSCs to oxidative damage. Efforts to overcome this limitation include the use of antioxidants. In this study, the role ofHibiscus sabdariffaL. (Roselle) in maintenance of cultured murine bone marrow-derived HSCs was investigated. Aqueous extract of Roselle was added at varying concentrations (0–1000 ng/mL) for 24 hours to the freshly isolated murine bone marrow cells (BMCs) cultures. Effects of Roselle on cell viability, reactive oxygen species (ROS) production, glutathione (GSH) level, superoxide dismutase (SOD) activity, and DNA damage were investigated. Roselle enhanced the survival(P<0.05)of BMCs at 500 and 1000 ng/mL, increased survival of Sca-1+cells (HSCs) at 500 ng/mL, and maintained HSCs phenotype as shown from nonremarkable changes of surface marker antigen (Sca-1) expression in all experimental groups. Roselle increased(P<0.05)the GSH level and SOD activity but the level of reactive oxygen species (ROS) was unaffected. Moreover, Roselle showed significant cellular genoprotective potency against H2O2-induced DNA damage. Conclusively, Roselle shows novel property as potential supplement and genoprotectant against oxidative damage to cultured HSCs.
Pricing of Two Kinds of Power Options under Fractional Brownian Motion, Stochastic Rate, and Jump-Diffusion Models
Authors: Xiang Kaili , Zhang Yindong , Mao Xiaotong
Published: October 2014

Option pricing is always one of the critical issues in financial mathematics and economics. Brownian motion is the basic hypothesis of option pricing model, which questions the fractional property of stock price. In this paper, under the assumption that the exchange rate follows the extended Vasicek model, we obtain the closed form of the pricing formulas for two kinds of power options under fractional Brownian Motion (FBM) jump-diffusion models.
An Efficient Approach for Solving Mesh Optimization Problems Using Newton’s Method
Authors: Kim Jibum
Published: October 2014

We present an efficient approach for solving various mesh optimization problems. Our approach is based on Newton’s method, which uses both first‐order (gradient) and second‐order (Hessian) derivatives of the nonlinear objective function. The volume and surface mesh optimization algorithms are developed such that mesh validity and surface constraints are satisfied. We also propose several Hessian modification methods when the Hessian matrix is not positive definite. We demonstrate our approach by comparing our method with nonlinear conjugate gradient and steepest descent methods in terms of both efficiency and mesh quality.
Pore Geometry Optimization of Titanium (Ti6Al4V) Alloy, for Its Application in the Fabrication of Customized Hip Implants
Authors: Roy Sandipan , Panda Debojyoti , Khutia Niloy , Chowdhury Amit Roy
Published: October 2014

The present study investigates the mechanical response of representative volume elements of porous Ti-6Al-4V alloy, to arrive at a desired range of pore geometries that would optimize the reduction in stiffness necessary for biocompatibility with the stress concentration arising around the pore periphery, under physiological loading conditions with respect to orthopedic hip implants. A comparative study of the two is performed with the aid of a newly defined optimizing parameter called pore efficiency that takes into consideration both the stiffness quantity and the stress localization around pores. To perform a detailed analysis of the response of the porous structure over the entire spectrum of loading conditions that a hip implant is subjected toin vivo, the mechanical responses of 3D finite element models of cubic and rectangular parallelepiped geometries, with porosities varying over a range of 10% to 60%, are simulated under representative compressive, flexural as well as combined loading conditions. The results that are obtained are used to suggest a range of pore diameters that lower the effective stiffness and modulus of the implant to around 60% of the stiffness and modulus of dense solid implants while keeping the stress levels within permissible limits.
Grooming Behavior in American Cockroach is Affected by Novelty and Odor
Authors: Zhukovskaya Marianna I.
Published: October 2014

The main features of grooming behavior are amazingly similar among arthropods and land vertebrates and serve the same needs. A particular pattern of cleaning movements in cockroaches shows cephalo-caudal progression. Grooming sequences become longer after adaptation to the new setting. Novelty related changes in grooming are recognized as a form of displacement behavior. Statistical analysis of behavior revealed that antennal grooming in American cockroach,Periplaneta americanaL., was significantly enhanced in the presence of odor.
Modification of Thionucleobases in Ionic Liquids
Authors: Hu Xiaomei , Zhang Bixian , Dong Shijia , Gao Yunfei
Published: October 2014

A simple method was established for the preparation of thio-substituted thionucleobases using room temperature ionic liquids (RTILs) such as 1-butyl-3-methylimidazolium trifluoroacetate [BMIM]+[CF3COO]−and 1-methoxyethyl-3-methylimidazolium trifluoroacetate [MeOEtMIM]+[CF3COO]−as solvents and catalysts without any other catalyst. These reactions proceeded efficiently in RTILs with excellent yield of products. RTILs can be recycled and reused effectively without further purification.
On Partial Charge Transfer Processes in Multiparticle Systems on Graphs
Authors: Chulaevsky Victor
Published: October 2014

We assess the probability of resonances between sufficiently distant states of an N-particle disordered quantum system in a combinatorial graph Z. In the N-particle configuration space, there are arbitrarily distant pairs of configurations giving rise to pairs of local (random) Hamiltonians which are strongly coupled, so that the eigenvalue concentration (EVC) bounds are difficult to obtain. We extend to any number of particles the efficient EVC bounds, obtained earlier for the 2-particle systems.
Atypical Reversible Leucoencephalopathy Syndrome after Bevacizumab/Folfox Regimen for Metastatic Colon Cancer
Authors: Salmi Narimane , Elghissassi Ibrahim , Bellahammou Khadija , Lakhdissi Asmaa , Mrabti Hind , Errihani Hassan
Published: October 2014

We are reporting a case of multifocal reversible leucoencephalopathy syndrome induced by chemotherapy based on Folfox-Bevacizumab regimen. A 44-year-old female, with no history of hypertension, received a chemotherapy based on Folfox-Bevacizumab for her metastatic colon cancer (5 FU: 325 mg/m2 d1 by intravenous infusion, Oxaliplatin 80 mg/m2 d1, and Bevacizumab: 7.5 mg/Kg d1). During the fourth cure, she presented delirium, seizures, and visual disturbances. The computed tomography (CT) of the brain showed hypodense lesions of the white matter of frontal, parietal, and occipital lobes, which were bilateral and symmetrical. The clinical table was reversible under symptomatic treatment.
Suaveolic Acid: A Potent Phytotoxic Substance ofHyptis suaveolens
Authors: Islam A. K. M. Mominul , Ohno Osamu , Suenaga Kiyotake , Kato-Noguchi Hisashi
Published: October 2014

Hyptis suaveolens(Lamiaceae) is an exotic invasive plant in many countries. Earlier studies reported that the aqueous, methanol, and aqueous methanol extract ofH. suaveolensand its residues have phytotoxic properties. However, to date, the phytotoxic substances of this plant have not been reported. Therefore, the objectives of this study were isolation and identification of phytotoxic substances ofH. suaveolens. Aqueous methanol extract of this plant was purified by several chromatographic runs through bioassay guided fractionation using garden cress (Lepidium sativum) as a test plant. Final purification of a phytotoxic substance was achieved by reverse phase HPLC and characterized as 14α-hydroxy-13β-abiet-8-en-18-oic acid (suaveolic acid) by high-resolution ESI-MS,1H-,13C-NMR, CD, and specific rotation. Suaveolic acid inhibited the shoot growth of garden cress, lettuce (Lactuca sativa), Italian ryegrass (Lolium multiflorum), and barnyard grass (Echinochloa crus-galli) at concentrations greater than 30 µM. Root growth of all but lettuce was also inhibited at concentrations greater than 30 µM. The inhibitory activities were concentration dependent. Concentrations required for 50% growth inhibition of suaveolic acid for those test plant species were ranged from 76 to 1155 µM. Therefore, suaveolic acid is phytotoxic and may be responsible for the phytotoxicity ofH. suaveolensplant extracts.
Multiple Marginal Tissue Recession Treated with a Simplified Lateral Sliding Flap Technique
Authors: Ribeiro Fernando Salimon , de Morais-Camillo Juliana Aparecida Najarro Dearo , Fernandes José Marcos Alves , Pires Juliana Rico , Zuza Elizangela Partata , Pontes Ana Emília Farias
Published: October 2014

Marginal tissue recession is a common esthetic problem that is usually accompanied by dentin sensitivity, and patients frequently report a fear of dental loss. Lateral sliding flaps have been used for localized recession, but they are rarely used for multiple recessions. The aim of this paper was to report a case of coverage of multiple marginal tissue recessions by means of a lateral sliding flap associated with a connective tissue graft. This was a modification of Nelson’s technique, which was originally described as the combination of the double papilla technique, lateral sliding flap, and connective tissue graft. In the present case, double papilla was not performed, rendering the maneuver less complicated. After surgery on teeth #23 to #25, total root coverage, decreased dentin sensitivity, and increased keratinized tissue band and gingival thickness were achieved. In the present case, modified Nelson technique proved to be a more simple procedure for the treatment of multiple recessions in one session, resulting in adequate healing, predictable root coverage, and, more importantly, esthetic and functional success.
Robust Initialization of Active Shape Models for Lung Segmentation in CT Scans: A Feature-Based Atlas Approach
Authors: Gill Gurman , Toews Matthew , Beichel Reinhard R.
Published: October 2014

Model-based segmentation methods have the advantage of incorporating a priori shape information into the segmentation process but suffer from the drawback that the model must be initialized sufficiently close to the target. We propose a novel approach for initializing an active shape model (ASM) and apply it to 3D lung segmentation in CT scans. Our method constructs an atlas consisting of a set of representative lung features and an average lung shape. The ASM pose parameters are found by transforming the average lung shape based on an affine transform computed from matching features between the new image and representative lung features. Our evaluation on a diverse set of 190 images showed an average dice coefficient of 0.746 ± 0.068 for initialization and 0.974 ± 0.017 for subsequent segmentation, based on an independent reference standard. The mean absolute surface distance error was 0.948 ± 1.537 mm. The initialization as well as segmentation results showed a statistically significant improvement compared to four other approaches. The proposed initialization method can be generalized to other applications employing ASM-based segmentation.
Changes in Vowel Articulation with Subthalamic Nucleus Deep Brain Stimulation in Dysarthric Speakers with Parkinson’s Disease
Authors: Martel Sauvageau Vincent , Macoir Joël , Langlois Mélanie , Prud’Homme Michel , Cantin Léo , Roy Johanna-Pascale
Published: October 2014

Purpose. To investigate changes in vowel articulation with the electrical deep brain stimulation (DBS) of the subthalamic nucleus (STN) in dysarthric speakers with Parkinson’s disease (PD).Methods. Eight Quebec-French speakers diagnosed with idiopathic PD who had undergone STN DBS were evaluated ON-stimulation and OFF-stimulation (1 hour after DBS was turned off). Vowel articulation was compared ON-simulation versus OFF-stimulation using acoustic vowel space and formant centralization ratio, calculated with the first (F1) and second formant (F2) of the vowels /i/, /u/, and /a/. The impact of the preceding consonant context on articulation, which represents a measure of coarticulation, was also analyzed as a function of the stimulation state.Results. Maximum vowel articulation increased during ON-stimulation. Analyses also indicate that vowel articulation was modulated by the consonant context but this relationship did not change with STN DBS.Conclusions. Results suggest that STN DBS may improve articulation in dysarthric speakers with PD, in terms of range of movement. Optimization of the electrical parameters for each patient is important and may lead to improvement in speech fine motor control. However, the impact on overall speech intelligibility may still be small. Clinical considerations are discussed and new research avenues are suggested.

Corrigendum to “Changes in Vowel Articulation with Subthalamic Nucleus Deep Brain Stimulation in Dysarthric Speakers with Parkinson’s Disease”
Giant Cell Arteritis in a 12-Year-Old Girl Presenting with Nephrotic Syndrome
Authors: El-Sayed Zeinab A. , El-Awady Hanaa M. , Hassan Zeinab E. , Adham Tamer M. H. , Mostafa Hossam M. , Elhefnawy Nadia G.
Published: October 2014

Giant cell arteritis (GCA) is rare in children. The kidneys are generally spared. We present a case of GCA in a 12-year-old girl with severe headache and tender scalp especially over the right temporal area. The right superficial temporal artery was cord like and nodular and the pulsations were barely felt. Several small tender nodular swellings were felt in the occipital area. She had been previously diagnosed as a case of nephrotic syndrome due to underlying membranoproliferative glomerulonephritis. This report is aimed at drawing attention to this rare form of vasculitis in children aiming at decreasing its morbidities.
Preoperative Diagnosis of Usual Leiomyoma, Atypical Leiomyoma, and Leiomyosarcoma
Authors: Matsuda M. , Ichimura T. , Kasai M. , Murakami M. , Kawamura N. , Hayashi T. , Sumi T.
Published: October 2014

Uterine smooth muscle tumors (SMTs) are common pelvic tumors in women, and most of them are diagnosed as usual leiomyoma (UL). Exclusion of malignant disease is important in the management of SMTs. However, differentiation of SMTs remains difficult. In this study, we aimed to improve the preoperative diagnosis of SMTs. We examined 21 ULs, 7 atypical leiomyomas (ALs), and 6 leiomyosarcomas (LMSs), all of which were diagnosed by uterine tumor biopsy. Immunohistochemical findings (low-molecular-mass polypeptide 2 (LMP2) and Ki-67) and clinical features (serum lactate dehydrogenase level and menopause) were evaluated. Statistically significant differences in the expression of LMP2 and Ki-67 were observed between UL and AL and between UL and LMS. The combined LMP2 and Ki-67 score was significantly different between UL and AL, between UL and LMS, and between AL and LMS. The combined immunohistochemistry and clinical findings score (total score) was also significantly different between pathological types. The findings of this study suggest that the accuracy of the preoperative diagnosis of SMTs may be improved by using a combination of immunohistochemical and clinical findings.
Fiber Bragg Grating-Based Performance Monitoring of Piles Fiber in a Geotechnical Centrifugal Model Test
Authors: Weng Xiaolin , Chen Jianxun , Wang Jun
Published: October 2014

In centrifugal tests, conventional sensors can hardly capture the performance of reinforcement in small-scale models. However, recent advances in fiber optic sensing technologies enable the accurate and reliable monitoring of strain and temperature in laboratory geotechnical tests. This paper outlines a centrifugal model test, performed using a 60 g ton geocentrifuge, to investigate the performance of pipe piles used to reinforce the loess foundation below a widened embankment. Prior to the test, quasidistributed fiber Bragg grating (FBG) strain sensors were attached to the surface of the pipe piles to measure the lateral friction resistance in real time. Via the centrifuge actuator, the driving of pipe piles was simulated. During testing, the variations of skin friction distribution along the pipe piles were measured automatically using an optical fiber interrogator. This paper represents the presentation and detailed analysis of monitoring results. Herein, we verify the reliability of the fiber optic sensors in monitoring the model piles without affecting the integrity of the centrifugal model. This paper, furthermore, shows that lateral friction resistance developed in stages with the pipe piles being pressed in and that this sometimes may become negative.
Long QTc Syndrome Type 2 Presenting in a Postpartum Patient on Medroxyprogesterone
Authors: Kern John , Duffy Margaret , Kern Corinne , Mazza Victor
Published: October 2014

Introduction. Congenital long QT syndrome type 2 (LQTS2) is a rare inherited cardiac abnormality resulting in increased risk of polymorphic ventricular tachycardia (PVT).Case Description. A 21-year-old postpartum female presented with syncopal episode after phone alarm. She was noted to have PVT on telemetry monitoring in the emergency department. EKG revealed QTc of 530. The patient’s only medication was medroxyprogesterone. She ultimately received a dual chamber pacemaker with ICD.Discussion. LQTS2 is associated with alarm sounds as a precipitating factor. Postpartum hormonal shifts as well as medroxyprogesterone have significant effect on native QTc duration.
The Response of Durum Wheat to the Preceding Crop in a Mediterranean Environment
Authors: Ercoli Laura , Masoni Alessandro , Pampana Silvia , Mariotti Marco , Arduini Iduna
Published: October 2014

Crop sequence is an important management practice that may affect durum wheat (Triticum durumDesf.) production. Field research was conducted in 2007-2008 and 2008-2009 seasons in a rain-fed cold Mediterranean environment to examine the impact of the preceding crops alfalfa (Medicago sativaL.), maize (Zea maysL.), sunflower (Helianthus annuusL.), and bread wheat (Triticum aestivumL.) on yield and N uptake of four durum wheat varieties. The response of grain yield of durum wheat to the preceding crop was high in 2007-2008 and was absent in the 2008-2009 season, because of the heavy rainfall that negatively impacted establishment, vegetative growth, and grain yield of durum wheat due to waterlogging. In the first season, durum wheat grain yield was highest following alfalfa, and was 33% lower following wheat. The yield increase of durum wheat following alfalfa was mainly due to an increased number of spikes per unit area and number of kernels per spike, while the yield decrease following wheat was mainly due to a reduction of spike number per unit area. Variety growth habit and performance did not affect the response to preceding crop and varieties ranked in the order Levante > Saragolla = Svevo > Normanno.