bluuebunny/crossref_metadata_2025 huggingface dataset:
Anti‐D prophylaxis: past, present and future
Authors: de Haas M. , Finning K. , Massey E. , Roberts D. J.
Published: January 2014

The new British Committee for Standards in Haematology (BCSH) guidelines for the use of anti‐D immunoglobulin in pregnancy provide a welcome clarification of the use of anti‐D in ectopic pregnancy and after red cell salvage during caesarean section, of dosing with different preparations and distinguishing non‐immune and immune anti‐D. The routine use of anti‐D prophylaxis (RAADP) to prevent Rhesus (Rh) D alloimmunisation during the third trimester is well established and requires careful and well‐audited local implementation to achieve the maximum public health benefit. In the UK, such scrutiny may be provided by the reporting of failed anti‐D prophylaxis at women who have produced an immune anti‐D that is detectable for the first time in the current pregnancy through the voluntary Serious Hazards of Transfusion reporting scheme (SHOT). Application of fetal RHD genotyping would avoid giving anti‐D to RhD negative women carrying an RhD negative fetus. RAADP is directed by fetal RHD genotyping in some countries in Northern Europe led by the Netherlands and Denmark. The economic case for RAADP directed by fetal RHD genotyping needs to be carefully evaluated and in England is under consideration by National Institute for Health and Clinical Excellence (NICE). Possible future developments include the use of monoclonal anti‐D preparations, now in advanced clinical trials, and also testing the hypothesis that directed RAADP from early in the second trimester may further reduce anti‐D immunisation.
Gamna‐Gandy bodies: a case of mistaken identity in the spleen of a cat
Authors: Ryseff Julia K. , Duncan Colleen , Sfiligoi Gabriella , Avery Paul R.
Published: January 2014

A 4‐year‐old, female spayed Domestic Shorthair cat was presented for a 2‐day history of lethargy, anorexia, and vomiting. Diagnostic assessments revealed a severe, regenerative anemia and the presence of a solitary, 3 × 4 cm splenic mass. Cytologic examination of fine‐needle aspirates of the splenic mass showed sheets of pleomorphic histiocytic cells with numerous intracellular and extracellular, negatively staining to deeply basophilic, branching structures. These structures were typically of thin uniform thickness with random angled branching that formed geometrical shapes and fragments, occasionally with sharpened ends and a crystalline appearance. Septal‐like divisions were irregularly spaced along some of the linear branches. The cytology was interpreted as a probable histiocytic inflammatory response to the unidentified foreign material with histiocytic sarcoma as a differential diagnosis. Histopathologic evaluation of the splenic mass resulted in a diagnosis of histiocytic sarcoma. The branching material stained positively for both iron and calcium, indicating that the material was compatible with Gamna‐Gandy bodies present secondary to tumor‐associated hemorrhage and the formation of calcium–iron complexes.
Osseous metaplasia within a canine insulinoma
Authors: Pieczarka Emily M. , Russell Duncan S. , Santangelo Kelly S. , Aeffner Famke , Burkhard Mary Jo
Published: January 2014

An 11‐year‐old male castrated mixed‐breed dog was presented for exercise intolerance, tetraparesis, and persistent hypoglycemia. Abdominal ultrasound examination revealed 2 nodules within the right limb of the pancreas. Cytology from one nodule was consistent with a carcinoma of neuroendocrine origin, with a primary differential diagnosis of insulinoma. Histologic evaluation and immunohistochemistry for synaptophysin and insulin confirmed the diagnosis of insulinoma. Additionally, there was a solitary nodule of mineralized compact bone composing approximately 60% of the mass. To the authors' knowledge, this is the first report of osseous metaplasia within an insulinoma (islet cell carcinoma).
Vasoactive agonists exert dynamic and coordinated effects on vascular smooth muscle cell elasticity, cytoskeletal remodelling and adhesion
Authors: Hong Zhongkui , Sun Zhe , Li Min , Li Zhaohui , Bunyak Filiz , Ersoy Ilker , Trzeciakowski Jerome P. , Staiculescu Marius Catalin , Jin Minshan , Martinez‐Lemus Luis , Hill Michael A. , Palaniappan Kannappan , Meininger Gerald A.
Published: January 2014

Key points

This study demonstrates rapid and dynamic changes in adhesion and cell elasticity following agonist stimulation that culminate in a remodelled cytoskeleton in vascular smooth muscle.

Evidence is presented that the changes in adhesion and elasticity are coordinated and that these variables demonstrate temporal oscillation consisting of three major oscillation components.

Eigen‐decomposition spectrum analysis revealed that these components of oscillation in cell elasticity and adhesion may be linked by shared signalling pathways.

Evidence is provided that the agonists angiotensin II and adenosine produce remodelling of actin cytoskeleton that may alter the properties of the observed oscillations in elasticity and adhesion.

It is concluded that angiotensin II and adenosine may regulate extracellular matrix adhesion and elasticity in vascular smooth muscle cells as a form of adaptation to more efficiently support contractile behaviour.

In this study, we examined the ability of vasoactive agonists to induce dynamic changes in vascular smooth muscle cell (VSMC) elasticity and adhesion, and tested the hypothesis that these events are coordinated with rapid remodelling of the cortical cytoskeleton. Real‐time measurement of cell elasticity was performed with atomic force microscopy (AFM) and adhesion was assessed with AFM probes coated with fibronectin (FN). Temporal data were analysed using an Eigen‐decomposition method. Elasticity in VSMCs displayed temporal oscillations with three components at approximately 0.001, 0.004 and 0.07 Hz, respectively. Similarly, adhesion displayed a similar oscillatory pattern. Angiotensin II (ANG II, 10−6 m) increased (+100%) the amplitude of the oscillations, whereas the vasodilator adenosine (ADO, 10−4 m) reduced oscillation amplitude (–30%). To test whether the oscillatory changes were related to the architectural alterations in cortical cytoskeleton, the topography of the submembranous actin cytoskeleton (100–300 nm depth) was acquired with AFM. These data were analysed to compare cortical actin fibre distribution and orientation before and after treatment with vasoactive agonists. The results showed that ANG II increased the density of stress fibres by 23%, while ADO decreased the density of the stress fibres by 45%. AFM data were supported by Western blot and confocal microscopy. Collectively, these observations indicate that VSMC cytoskeletal structure and adhesion to the extracellular matrix are dynamically altered in response to agonist stimulation. Thus, vasoactive agonists probably invoke unique mechanisms that dynamically alter the behaviour and structure of both the VSMC cytoskeleton and focal adhesions to efficiently support the normal contractile behaviour of VSMCs.
Acute pancreatitis decreases the sensitivity of pancreas‐projecting dorsal motor nucleus of the vagus neurones to group II metabotropic glutamate receptor agonists in rats
Authors: Babic Tanja , Travagli R. Alberto
Published: January 2014

Key points

Acute pancreatitis is one of the most severe disorders of the exocrine pancreas.

Pancreatic exocrine secretions (PES) are under regulatory control of dorsal motor nucleus of the vagus (DMV) neurones and their activity is regulated by inhibitory GABAergic and excitatory glutamatergic synaptic inputs.

Group II metabotropic glutamate receptors (mGluR) decrease synaptic transmission to pancreas‐projecting DMV neurones and modulate PES.

In this study, we show that acute pancreatitis induces a long‐lasting increase in excitatory synaptic transmission to pancreas‐projecting neurones by decreasing the response of excitatory synaptic terminals to group II mGluR agonists.

These data suggest that changes in group II mGluR expression in the DMV may underlie short‐ and long‐term changes in PES in acute pancreatitis.

Recent studies have shown that pancreatic exocrine secretions (PES) are modulated by dorsal motor nucleus of the vagus (DMV) neurones, whose activity is finely tuned by GABAergic and glutamatergic synaptic inputs. Group II metabotropic glutamate receptors (mGluR) decrease synaptic transmission to pancreas‐projecting DMV neurones and increase PES. In the present study, we used a combination of in vivo and in vitro approaches aimed at characterising the effects of caerulein‐induced acute pancreatitis (AP) on the vagal neurocircuitry modulating pancreatic functions. In control rats, microinjection of bicuculline into the DMV increased PES, whereas microinjections of kynurenic acid had no effect. Conversely, in AP rats, microinjection of bicuculline had no effect, whereas kynurenic acid decreased PES. DMV microinjections of the group II mGluR agonist APDC and whole cell recordings of excitatory currents in identified pancreas‐projecting DMV neurones showed a reduced functional response in AP rats compared to controls. Moreover, these changes persisted up to 3 weeks following the induction of AP. These data demonstrate that AP increases the excitatory input to pancreas‐projecting DMV neurones by decreasing the response of excitatory synaptic terminals to group II mGluR agonist.
The Effect of Adding Core Stability Training to a Standard Balance Exercise Program on Sit to Stand Performance in Older Adults: A Pilot Study
Authors: Arnold Cathy , Lanovaz Joel , Oates Alison , Craven Bruce , Butcher Scotty
Published: January 2014

This study compared sit to stand (STS) performance between older adults in a nine-week training program focusing on core stability exercises to enhance balance and postural control (EB) versus standard balance (SB) exercises. Repetitions in 30 s (STSreps) and kinematic performance (vertical and horizontal momentum, and margin of stability) were measured pre and postintervention in 23 older adults with at least one fall risk factor. Although both groups combined improved STSreps (P = .001) and vertical momentum (.008), a significant between-group difference was observed for completers only (MANCOVA of posttest group differences, with pretest scores as covariates; P = .04). EB demonstrated a greater but nonsignificant improvement in vertical momentum (P = .095). In conclusion, core stability training added to SB did not result in STS reps improvement. Compliance may modify these results and future larger sample studies should evaluate the impact of core stability training on STS biomechanics.
Positive and Negative Factors That Influence Concussion Reporting Among Secondary-School Athletes
Authors: Kay Melissa C. , Welch Cailee E. , McLeod Tamara C. Valovich
Published: January 2014

Clinical Scenario:

Concussions are one of the most common sport-related injuries affecting athletes participating at all levels across a variety of sports. It has been reported that up to 3.8 million concussive events occur per year that are sports-related. One significant issue with identifying concussions is that a clinical diagnosis is based on the presence of signs and symptoms, which are self-reported by the patient. In the adolescent population, injury to the brain is possible with even the slightest insult, which can affect recovery and predispose them to subsequent concussions. Recent legislative efforts have included athlete education as a means to improve concussion reporting. More specifically, all 50 US states and the District of Columbia have implemented concussion legislation that includes some type of concussion education protocol, but there is still little evidence to suggest that enhanced knowledge levels result in behavior changes, including improved concussion-reporting practices. It is unclear what factors make an adolescent athlete more or less likely to report the symptoms of a concussion.

Focused Clinical Question:

What factors positively or negatively influence secondary school athletes’ likelihood of reporting symptoms of sport-related concussions?
Roquin-2 Promotes Ubiquitin-Mediated Degradation of ASK1 to Regulate Stress Responses
Authors: Maruyama Takeshi , Araki Toshihiro , Kawarazaki Yosuke , Naguro Isao , Heynen Susanne , Aza-Blanc Pedro , Ronai Ze’ev , Matsuzawa Atsushi , Ichijo Hidenori
Published: January 2014

Roquin-2 promotes degradation of the kinase ASK1 to mediate an appropriate response to oxidative stress and infection.
Acute inferior myocardial infarction in a young male patient associated with Behcet's disease and sildenafil
Authors: Cetin Mustafa , Ozturk Unal , Cakici Musa , Yildiz Emrah
Published: January 2014

Behcet’s disease (BD) is a multisystemic inflammatory disorder of unknown origin, presenting with mucocutaneous, ocular, articular, vascular, gastrointestinal and central nervous system manifestations. Coronary involvement is very rare in patients with BD. Sildenafil, an oral drug used to treat erectile dysfunction, was shown to cause significant cardiovascular problems including acute myocardial infarction (MI) and sudden cardiac death. Acute MI associated with BD and sildenafil has not been reported previously. We present a case of a 23-year-old male patient with an acute inferior MI associated with BD diagnosed after admission of sildenafil, who was successfully treated with thrombus aspiration and tirofiban administration.
Monsters do exist: an unusual case of chest pain
Authors: Thomas Mari Lluon
Published: January 2014

A 19-year-old man presented to the emergency department with a 3-week history of chest pain. Despite normal examination, bloods and observations of his chest X-ray revealed a large opacity in the middle and lower right zone. Further imaging revealed a multicystic mediastinal teratoma. He was admitted under the respiratory physicians who arranged further investigations and discussed his case with the lung and testicular multidisciplinary team. He was started on neoadjuvant chemotherapy with a plan for future definitive surgical resection. Four months later he suddenly deteriorated due to airway compression from the tumour. He underwent an emergency thoracotomy and tumour resection. He is currently doing well and is thought to have a good prognosis following complete resection of his tumour. This case report summarises this rare diagnosis and emphasises the need for careful evaluation of patients despite their initial well appearance, especially in patients who are reattending.
Synthesis, characterization, and adsorption properties of a Ce(III)-imprinted polymer supported by mesoporous SBA-15 matrix by a surface molecular imprinting technique
Authors: Liu Yan , Tian Sujun , Meng Xiangguo , Dai Xiaohui , Liu Zhanchao , Meng Minjia , Han Juan , Wang Yun , Chen Rui , Yan Yongsheng , Ni Liang
Published: January 2014

A new Ce(III) ion imprinted polymer (Ce(III)-IIP), which can be used for selective removal of Ce(III) from aqueous solutions, was successfully prepared based on the matrix material of ordered mesoporous silica SBA-15 by surface molecular imprinting technology. The prepared polymer was characterized by X-ray diffraction, transmission electron microscopy, Fourier transmission infrared spectrometry, and nitrogen adsorption−desorption isotherm. The results showed that Ce(III)-IIP kept a uniform framework mesoporosity of SBA-15 but a decrease in Brunauer−Emmett−Teller surface area, pore volume, and average pore diameter. Batch adsorption tests were researched on the effects of solution pH value, mass of sorbent, and contact time at different initial Ce(III) concentrations and temperatures. The kinetic data well fitted the pseudo-second-order kinetic model compared with the pseudo-first-order model. The adsorption isotherm fitted Langmuir model and the dimensionless separation factor RL indicated favorable adsorption. In addition, the Gibbs free energy (ΔG0), entropy (ΔS0), and enthalpy (ΔH0) were calculated from the adsorption data. These values suggested that the adsorption of Ce(III) onto Ce(III)-IIP was a spontaneous and endothermic nature of the process. The relative selectivity coefficients for different metal ion were larger than that of the nonimprinted polymer, indicating that Ce(III)-IIP synthesized for Ce(III) had a higher selectivity specialism for this ion.
Cucurbit[7]uril host−guest complexations of steroidal neuromuscular blocking agents in aqueous solution
Authors: Gamal-Eldin Mona A. , Macartney Donal H.
Published: January 2014

The complexations of three steroidal neuromuscular blocking agents, rocuronium, vecuronium, and pancuronium, by the cucurbit[7]uril host molecule have been investigated in aqueous solution using 1H NMR spectroscopy and ESI mass spectrometry. The CB[7] binds to each of the two terminal cationic N-heterocyclic groups by means of ion-dipole interactions and hydrophobic effects, with stability constants in the order of vecuronium > pancuronium > rocuronium. This trend is different from those observed for the anionic substituted γ-cyclodextrin (Sugammadex), currently employed as a neuromuscular blockade reversal agent, and an acylic glycoluril tetramer (Calabadion), recently reported to reverse both steroidal and benzylisoquinolium neuromuscular blocking agents in rats.
SELF-TUNING OPTIMIZATION ON STORAGE SERVERS IN PARALLEL FILE SYSTEMS
Authors: LIAO JIANWEI
Published: January 2014

This paper proposes a framework, which requires keeping tracks of both logical I/O access operations and their corresponding physical access on the storage servers in a parallel file system, to build a self-tuning storage system. Thus, the built self-tuning storage system is able to support dynamical data migrating and data pre-fetching transparently from the view point of clients to boost I/O performance. To this end, we first devised an approach to find out the pairs of logical I/O operations and their associated physical I/O operations. We then employed working set modeling to form I/O access patterns and their corresponding disk access patterns. Finally, with the information about existing access patterns and the similarity analysis of access patterns, it is not difficult to predict the future I/O access operations for possible I/O optimization. Through a series of experiments based on several realistic benchmarks, we show that the newly proposed self-tuning storage system is capable of enabling data migration and data pre-fetching dynamically by using the information about I/O access patterns and the predicted future I/O operations. Therefore, it can improve I/O data throughput significantly for the applications with complicated access patterns; especially, for the applications that require to process multiple-dimensional data, such as medical image processing applications and geographic information system (GIS) applications.
ON THE GAP OF HAMILTONIANS FOR THE ADIABATIC SIMULATION OF QUANTUM CIRCUITS
Authors: GANTI ANAND , SOMMA ROLANDO
Published: January 2014

The time or cost of simulating a quantum circuit by adiabatic evolution is determined by the spectral gap of the Hamiltonians involved in the simulation. In "standard" constructions based on Feynman's Hamiltonian, such a gap decreases polynomially with the number of gates in the circuit, L. Because a larger gap implies a smaller cost, we study the limits of spectral gap amplification in this context. We show that, under some assumptions on the ground states and the cost of evolving with the Hamiltonians (which apply to the standard constructions), an upper bound on the gap of the order 1/L follows. In addition, if the Hamiltonians satisfy a frustration-free property, the upper bound is of the order 1/L2. Our proofs use recent results on adiabatic state transformations, spectral gap amplification, and the simulation of continuous-time quantum query algorithms. They also consider a reduction from the unstructured search problem, whose lower bound in the oracle cost translates into the upper bounds in the gaps. The impact of our results is that improving the gap beyond that of standard constructions (i.e. 1/L2), if possible, is challenging.
P3HT CHAIN MORPHOLOGY IN COMPOSITE P3HT/PCBM NANOPARTICLES STUDIED BY SINGLE PARTICLE FLUORESCENCE EXCITATION POLARIZATION SPECTROSCOPY
Authors: SCHNEIDER-POLLACK SAMANTHA , DOSHI MONA , GELDMEIER JEFF , GESQUIERE ANDRE J.
Published: January 2014

The use of conjugated polymers such as poly(3-hexylthiophene) (P3HT) in the active layers of plastic electronic devices could provide a more practical and accessible form of energy production and storage. The efficiency of these devices is intimately connected to the morphology of the polymer chains in the active layer materials, as polymer folding affects mesoscale material morphology. The latter in turn influences electronic structure and thus performance of the active layer. It is, however, highly challenging to determine molecular structure and folding properties in a bulk material. Here, it is shown that through the use of nanoparticles as a model system for the bulk material insight in molecular morphology can be gained through single particle fluorescence excitation spectroscopy. The study of P3HT chain morphologies was accomplished through the investigation of neat (0 wt% PCBM) P3HT nanoparticles and 25, 50 and 75 wt% PCBM blended P3HT nanoparticles. A striking discontinuous trend in P3HT chain morphology as a function of PCBM blending ratio was observed, where P3HT morphologies at 25 wt% and 75 wt% blending ratios appear to be more disordered than those observed for the 50 wt% blending ratio. These data suggest that at least from the morphological perspective, the 1:1 blending ratio appears to yield the better P3HT chain alignment.

[Formula: see text]Special Issue Comment: This paper about solving single molecule conformations is related to the papers in this Special Issue on mathematical models for treatment of single molecule trajectories,1 nonblinking inorganic nanocrystals,2 and hybrid quantom dot–fullerence composite nanoparticles.3
INTRODUCTION
Authors: TEN BRUMMELAAR T. , TUTHILL P. , VAN BELLE G.
Published: January 2014

After nearly one and a half centuries of effort, one of the most pernicious problems in observational astronomy — obtaining resolved images of the stars — is finally yielding to advances in modern instrumentation. The exquisite precision delivered by today's interferometric observatories is rapidly being applied to more and more branches of optical astronomy. The most capable interferometers in the Northern Hemisphere, both located in the United States are the Navy Precision Optical Interferometer (NPOI) in Arizona and the Center for High Angular Resolution Astronomy Array (CHARA) run by Georgia State University and located in California. In early 2013 these two groups held a joint meeting hosted by the Lowell Observatory in Flagstaff. All major groups working in the field were represented at this meeting and it was suggested to us by this Journal that this was an excellent opportunity to put together a special issue on interferometry. In order to be as broad as possible, those who did not attend the CHARA/NPOI meeting were also solicited to make a contribution. The result is this collection of papers representing a snap shot of the state of the art of ground based optical and near infrared interferometry.
ICONN — THE INFRARED COHERENCING NEAREST NEIGHBOR TRACKER
Authors: JURGENSON C. A. , SANTORO F. G. , MCCRACKEN T. M. , YOUNG J. S. , SENETA E. , BUSCHER D. F. , CREECH-EAKMAN M. , HANIFF C.
Published: January 2014

ICONN is a dedicated fringe tracker for the Magdalena Ridge Observatory Interferometer (MROI) that employs a baseline bootstrapping combination scheme utilizing the interferometer's "Y"-shaped telescope array. The ICONN optomechanics are designed in a modular fashion to combine light from two to ten telescopes while tracking on the nearest neighbor baselines. The software tasked with operating ICONN is designed to interface with the larger MROI software supervisory system. Commands are distributed to high level processes within ICONN, which in turn pass them down internally to lower level threads. The design of ICONN is now complete and laboratory testing has commenced. This paper details the optomechanical and software design of ICONN.
PORTABLE SPECKLE INTERFEROMETRY CAMERA SYSTEM
Authors: GENET R. M.
Published: January 2014

Speckle interferometry of close double stars avoids seeing limitations through a series of diffraction-limited high speed observations made faster than the atmospheric coherence time scale. Electron multiplying CCD cameras have low read noise at high read speeds, making them ideal for speckle interferometry. A portable speckle camera system was developed based on relatively low cost, off-the-shelf components. The camera's modular components can be exchanged to adapt the system to a wide range of telescopes.
EXPANDING THE CHARA/FLUOR HOT DISKS SURVEY
Authors: MENNESSON B. , SCOTT N. , TEN BRUMMELAAR T. , BRYDEN G. , TURNER N. , ABSIL O. , MILLAN-GABET R. , COUDE DU FORESTO V. , AUGEREAU J. C. , RIDGWAY S. , LEBRETON J. , MARION L.
Published: January 2014

Little is presently known about the hot (>300 K) dust component of debris disks surrounding main sequence stars, similar to the zodiacal dust cloud found in the inner solar system. While extensive surveys have been carried out from space, the majority of detections have surprisingly come from the ground, where near infrared interferometric observations have recently revealed small (~1%) resolved excesses around a dozen nearby main sequence stars. Most of these results have come from the CHARA array "FLUOR" instrument (Mt. Wilson, CA), which has demonstrated the best sensitivity worldwide so far for this type of studies, and has carried out an initial survey of ~40 stars. In order to further understand the origin of this "hot dust phenomenon", we will extend this initial survey to a larger number of stars and lower excess detection limits, i.e. higher visibility accuracy providing higher contrast measurements. To this end, two major instrumental developments are underway at CHARA. The first one aims at improving FLUOR's sensitivity to a median K-band magnitude limit of 5 (making 200 targets available). The second development is based on a method that we recently developed for accurate (better than 0.1%) null depth measurements of stars, and that can be extended to regular interferometric visibility measurements.
Interview with David Hicks
Authors: Atzenbeck Claus
Published: January 2014

David Hicks is an Associate Professor with the Institute for Electronic Systems at Aalborg University. Previously he has served as Department Head for the Department of Computer Science and Engineering at Aalborg University's Esbjerg campus. He has also held positions in international research labs in the US as well as Europe, and spent time as a senior researcher in the software industry. He has served in a variety of capacities in the hypertext community including Vice Chair for SIGWEB.
"A semantics-based approach to machine perception" by Cory Andrew Henson, with Prateek Jain as coordinator
Authors: Henson Cory Andrew
Published: January 2014

Machine perception can be formalized using semantic web technologies in order to derive abstractions from sensor data using background knowledge on the Web, and efficiently executed on resource-constrained devices.
"Building a search engine for algorithms" by Suppawong Tuarob, Prasenjit Mitra, and C. Lee Giles with Martin Vesely as coordinator
Authors: Tuarob Suppawong , Mitra Prasenjit , Giles C. Lee
Published: January 2014

A significant number of scholarly articles in computer science and other disciplines contain algorithms that provide concise descriptions for solving a wide variety of computational problems. Automatically finding and extracting these algorithms in scholarly digital documents would make possible algorithm indexing, searching, discovering, and analysis. Currently, only well known algorithms are cataloged. In order to find new and cutting-edge algorithms, a user must manually search through a large collection of scholarly documents or author homepages. In this article, we describe an initial prototype of
AlgorithmSeer
, a system for extracting, indexing, and searching for algorithms in scholarly documents. The initial system has been tested as part of the CiteSeer

X

digital library and search engine. Current issues and future directions, such as algorithm information extraction and classification, are also discussed.
Probing a M/G/1 queue with general input and service times
Authors: Antunes Nelson , Jacinto Gonçalo , Pacheco António
Published: January 2014

We consider the estimation of the arrival rate and the service time moments of a M/G/1 queue with probing, i.e., with special customers (probes) entering the system. The probe inter-arrival times are i.i.d. and probe service times follow a general positive distribution. The only observations used are the arrival times, service times and departure times of probes. We derive the main equations from which the quantities of interest can be estimated. Two particular probe arrivals, deterministic and Poisson, are investigated.
Fluid approximations of many-server queues with delayed feedback and heterogeneous service and patience times
Authors: Kang Weining , Lu Hongyuan , Pang Guodong
Published: January 2014

We consider many-server queues with delayed feedback where the service (patience) times of new customers and feedback customers are differentiated, and new and feedback customers are served under the first-come-first-serve (FCFS) discipline in the service station. The arrival process, service, patience and delay times are all general and mutually independent. A two-parameter fluid model for the system dynamics in the many-server regime is investigated, where we use four two-parameter processes to describe the service and queueing processes of the new and feedback customers, two for the service dynamics and two for the queueing dynamics. When the arrival rate is constant, we derive the steady state performance measures and study the impact of impatience differentiation and service differentiation upon them. When the arrival rate is time-varying, we provide an algorithm to compute the fluid processes. Numerical experiments are conducted, and show that the algorithm is very effective, compared with simulations.
Interchange of limits in heavy traffic analysis under a moment condition
Authors: Ye Heng-Qing , Yao David D.
Published: January 2014

We develop an approach to prove the interchange of limits in heavy traffic analysis of stochastic processing networks, using a moment condition on the primitive data, the interarrival and service times. The approach complements the one in [8], where a bounded workload condition is required instead.
Battery provisioning and scheduling for a hybrid battery-diesel generator system
Authors: Singla Sahil , Ghiassi-Farrokhfal Yashar , Keshav Srinivasan
Published: January 2014

Diesel generators (gensets) are commonly used to provide a reliable source of electricity in off-grid locations. Operating a genset is expensive both in terms of fuel and carbon footprint. Because genset efficiency increases with offered load, this expense can be reduced by using a storage battery to ensure that a genset always runs at full load, charging and discharging the battery as necessary. However, the cost of batteries requires us to size them parsimoniously and operate them efficiently. We, therefore, study the problem of provisioning and optimally managing a battery in a hybrid batterygenset system. To aid in sizing a battery, we analytically study the trade-off between battery size and carbon footprint. We also formulate the optimal scheduling of battery charging and discharging as a mixed-integer program, proving that it is NP-hard. We then propose a heuristic online battery scheduling scheme that we call alternate scheduling and prove that it has a competitive ratio of
k
1
G
/
C
+
k
2

T
u

/
k
1
+
k
2

T
u

with respect to the offline optimal scheduling, where G is the genset capacity, C is the battery charging rate, k1, k2 are genset-specific constants, and Tu is the duration of a time step. We numerically demonstrate that alternate scheduling is near-optimal for four selected industrial loads.
Real-time deferrable load control
Authors: Gan Lingwen , Wierman Adam , Topcu Ufuk , Chen Niangjun , Low Steven H.
Published: January 2014

Real-time demand response is potential to handle the uncertainties of renewable generation. It is expected that a large number of deferrable loads, including electric vehicles and smart appliances, will participate in demand response in the future. In this paper, we propose a decentralized algorithm that reduces the tracking error between demand and generation, by shifting the power consumption of deferrable loads to match the generation in real-time. At each time step within the control window, the algorithm minimizes the expected tracking error to go with updated predictions on demand and generation. It is proved that the root mean square tracking error vanishes as control window expands, even in the presence of prediction errors.
Outage-capacity tradeoff for smart grid with renewables
Authors: Yang Kai , Walid Anwar
Published: January 2014

Future power grid systems are envisioned to be integrated with many distributed renewable energy sources (DRES). Energy storage is the key technology to enable reliable and cost-effective renewable energy. Given the fact that largescale energy storage device is usually costly to install and operate, we are naturally led to the following question: How much storage is needed to guarantee the stability of a power grid network with DRESs? This paper represents a first step in systematically exploring the tradeoff between the capacity of energy storage devices and the outage probability, i.e., the probability of the occurrence of imbalance between the supply and demand. We first propose a secure scheduling and dispatch (SSD) algorithm that is capable of maintaining the grid stability in the presence of volatility in the power generation. We then derive a closed-form bound to quantify the tradeoff between the storage capacity and the outage probability. Under mild assumptions, we reveal that, the outage probability decreases exponentially with respect to the square of the storage capacity. This finding implies that energy storage is an effective and economically viable solution to maintain the stability of a smart grid network even in the presence of many volatile and intermittent renewable energy sources. The impact of correlation in energy generation on the stability of a smart grid network is also investigated.
Correcting vibration-induced performance degradation in enterprise servers
Authors: Chan Christine S. , Pan Boxiang , Gross Kenny , Vaidyanathan Kalyan , Rosing Tajana Šimunić
Published: January 2014

Server fan subsystems are power-hungry and generate vibrations, degrading the performance of data-intensive workloads and inflating the uptime electric bills of cost-sensitive datacenters. In this paper, we demonstrate a systematic server measurement methodology to isolate different types of vibrations and quantify their effect on hard disks. We introduce a thermal and cooling management policy that mitigates vibrational effects workload scheduling and fan control, and study the benefits of a hybrid storage array with solid-state drives (SSDs) that are impervious to vibrations. We achieve performance improvements of up to 73% and energy savings of up to 76% over the state of the art, while meeting thermal constraints and improving the system's resilience to both internal and external vibrations.
A hop-by-hop energy efficient distributed routing scheme
Authors: Hou Chenying , Zhang Fa , Anta Antonio Fernández , Wang Lin , Liu Zhiyong
Published: January 2014

Energy inefficiencies in current networks provide both challenges and opportunities for energy saving. Recently, there are many works focusing on minimizing energy cost from the routing perspective. However, most existing work view them as optimization problems and solve them in a centralized manner such as with a solver or using approximations. In this paper, we focus on a network-wide bi-objective optimization problem, which simultaneously minimizes the total energy consumption using speed scaling and the total traffic delay. We propose a hop-by-hop dynamic distributed routing scheme for the implementation of this network-wide optimization problem. Our scheme is more practical to realize in large distributed networks compared with current centralized energy minimization methods. We can also achieve near global optimal in a distributed manner, while most used shortest path routing protocols such as OSPF cannot make it. Our routing scheme is totally distributed and maintains loop-free routes in every instant. Simulations conducted in real data sets show that the distributed loop-free routing scheme converges to near Pareto optimal values. Also, our method outperforms the widely applied shortest path routing strategy by 30% in energy saving.
Estimating internet address space usage through passive measurements
Authors: Dainotti Alberto , Benson Karyn , King Alistair , claffy kc , Kallitsis Michael , Glatz Eduard , Dimitropoulos Xenofontas
Published: January 2014

One challenge in understanding the evolution of Internet infrastructure is the lack of systematic mechanisms for monitoring the extent to which allocated IP addresses are actually used. Address utilization has been monitored via actively scanning the entire IPv4 address space. We evaluate the potential to leverage passive network traffic measurements in addition to or instead of active probing. Passive traffic measurements introduce no network traffic overhead, do not rely on unfiltered responses to probing, and could potentially apply to IPv6 as well. We investigate two challenges in using passive traffic for address utilization inference: the limited visibility of a single observation point; and the presence of spoofed IP addresses in packets that can distort results by implying faked addresses are active. We propose a methodology for removing such spoofed traffic on both darknets and live networks, which yields results comparable to inferences made from active probing. Our preliminary analysis reveals a number of promising findings, including novel insight into the usage of the IPv4 address space that would expand with additional vantage points.
Enlarging the SIGCOMM tent
Authors: McKeown Nick
Published: January 2014

At every Sigcomm conference the corridors buzz with ideas about how to improve Sigcomm. It is a healthy sign that the premier conference in networking keeps debating how to reinvent and improve itself. In 2012 I got the chance to throw my hat into the ring; at the end of a talk I spent a few minutes describing why I think the Sigcomm conference should be greatly expanded. A few people encouraged me to write the ideas down.

My high level goal is to enlarge the Sigcomm tent, welcoming in more researchers and more of our colleagues from industry. *More researchers* because our field has grown enormously in the last two decades, and Sigcomm has not adapted. I believe our small program limits the opportunities for our young researchers and graduate students to publish new ideas, and therefore we are holding back their careers. *More colleagues from industry* because too few industry thought-leaders are involved in Sigcomm. The academic field of networking has weak ties to the industry it serves, particularly when compared to other fields of systems research. Both sides lose out: there is very little exchange and transfer of ideas in either direction, and not enough vigorous debate about the directions networking should be heading.
Incidence and Significance of Early Recurrences of Atrial Fibrillation After Cryoballoon Ablation
Authors: Andrade Jason G. , Khairy Paul , Macle Laurent , Packer Doug L. , Lehmann John W. , Holcomb Richard G. , Ruskin Jeremy N. , Dubuc Marc
Published: January 2014

Background—

Early recurrence of atrial fibrillation (ERAF) is common after radiofrequency catheter ablation for AF. We sought to determine the incidence and prognostic significance of ERAF after cryoballoon ablation. Moreover, the benefit of early reablation for ERAF after cryoballoon ablation is undetermined.

Methods and Results—

The Sustained Treatment of Paroxysmal Atrial Fibrillation (STOP AF) trial randomized 245 patients with paroxysmal AF to medical therapy versus cryoballoon-based pulmonary vein ablation. Patients were followed for 12 months. ERAF was defined as any recurrence of AF >30 seconds during the first 3 months of follow-up. Late recurrence (LR) was defined as any recurrence of AF >30 seconds between 3 and 12 months. Of the 163 patients randomized to cryoablation, 84 patients experienced ERAF (51.5%). The only significant factor associated with ERAF was male sex (hazard ratio [HR], 2.18; 95% confidence interval [CI], 1.03–4.61;
P
=0.041). LR was observed in 41 patients (25.1%), and was significantly related to ERAF (55.6% LR with ERAF versus 12.7% without ERAF;
P
<0.001). Among patients with ERAF, only current tobacco use (HR, 3.84; 95% CI, 1.82–8.11;
P
<0.001) was associated with LR. Conversely, early reablation was associated with greater freedom from LR (3.3% LR with early reablation versus 55.6% without; HR, 0.04; 95% CI, 0.01–0.32;
P
=0.002).

Conclusions—

ERAF after cryoballoon ablation occurs in ≈50% of patients and is strongly associated with LR. Early reablation for ERAF is associated with excellent long-term freedom from recurrent AF.
Impact of Programming Strategies Aimed at Reducing Nonessential Implantable Cardioverter Defibrillator Therapies on Mortality
Authors: Tan Vern Hsen , Wilton Stephen B. , Kuriachan Vikas , Sumner Glen L. , Exner Derek V.
Published: January 2014

Background—

Patients who receive implantable cardioverter defibrillator therapies are at higher risk of death versus those who do not. Programmed settings to reduce nonessential implantable cardioverter defibrillator therapies (therapy reduction programming) have been developed but may have adverse effects. This systematic review and meta-analysis assessed the relationship between therapy reduction programming with the risks of death from any cause, implantable cardioverter defibrillator shocks, and syncope.

Methods and Results—

MEDLINE, EMBASE, and
clinicaltrials.gov
databases were searched to identify relevant studies. Those that followed patients for ≥6 months and reported mortality were included. Six met the inclusion criteria; 4 randomized (Comparison of Empiric to Physician-Tailored Programming of ICDs [EMPIRIC], Multicenter Automatic Defibrillator Implantation Trial—Reduce Inappropriate Therapy [MADIT-RIT], Avoid Delivering Therapies for Non-sustained Arrhythmias in ICD Patients III [ADVANCE III], and Programming Implantable Cardioverter-Defibrillators in Patients with Primary Prevention Indication to Prolong Time to First Shock [PROVIDE]) and 2 prospective studies (Role of Long Detection Window Programming in Patients With Left Ventricular Dysfunction, Non-ischemic Etiology in Primary Prevention Treated with a Biventricular ICD [RELEVANT] and Primary Prevention Parameters Evaluation [PREPARE]). These 6 studies included 7687 (3598 conventional and 4089 therapy reduction programming) patients. Most (77%) participants were men, had a history of ischemic heart disease (56%), and were prescribed β-blockers (84%). Therapy reduction programming was associated with a 30% relative reduction in mortality (95% confidence interval, 16%–41%;
P
<0.001). No significant heterogeneity among studies was observed (
P
=0.6). A similar 26% reduction in mortality was observed when only the 4 randomized trials were included (95% confidence interval, 11%–40%;
P
=0.002). These results were not significantly altered after adjustment for baseline characteristics. No significant difference in the risk of syncope was observed with conventional versus therapy reduction programming (
P
=0.5).

Conclusions—

Therapy reduction programming results in a large, significant, and consistent reduction in mortality, with no apparent increase in the risk of syncope.
Two new species of Rigidoporus (Agaricomycetes) from Brazil and new records from the Brazilian Amazonia
Authors: GOMES-SILVA ALLYNE CHRISTINA , DE MEDEIROS PRISCILA SANJUAN , SOARES ADRIENE MAYRA DA SILVA , SOTÃO HELEN MARIA PONTES , RYVARDEN LEIF , GIBERTONI TATIANA BAPTISTA
Published: January 2014

Two new polypores, Rigidoporus grandisporus and R. mariae are described from the Brazilian Amazonia based on specimens deposited in herbarium INPA between 27 and 39 years ago, and material recently collected in the State of Par￡. Besides the description of the new species, R. crocatus and R. undatus are reported as new records from the Brazilian Amazonia. Rigidoporus amazonicus, R. lineatus, R. ulmarius and R. vinctus are new records to different states of the Brazilian Amazonia. A key to the Rigidoporus species known for the Neotropics is provided.
Salvia guaneorum (Labiatae), a new species from the Chicamocha Canyon, Colombia
Authors: Fernández-Alonso Jose Luis
Published: January 2014

A new species of Salvia subgen. Calosphace from the Chicamocha Canyon, in the Eastern Cordillera of Colombia is described and illustrated. The morphological affinities and putative relatives with other Colombian species of the sections Angulatae and Longipes are discussed.
Hieracium sudetotubulosum (Asteraceae), a new name for the illegitimate H. tubulosum (Tausch) Tausch
Authors: Szelag Zbigniew
Published: January 2014

Hieracium alpinum var. tubulosum Tausch (1828: 63) was raised to species rank as H. tubulosum (Tausch) Tausch (1837: 68), an illegitimate homonym of H. tubulosum Lamarck (1786: 367). The latter is a different, unrelated species pertaining to the H. intybaceum aggregate and described from the Alps, whereas Tausch’s taxon is endemic to the Sudetes and belongs to the H. alpinum aggregate (Chrtek, 1997). Hieracium tubulosum (Tausch) Tausch differs from other central European species of the H. alpinum aggregate by having tubular florets, so that the replacement name proposed below is etymologically appropriate.
American engagement and the pathways to Arab–Israeli peace
Authors: Pressman Jeremy
Published: January 2014

This close empirical study of decades of US efforts to bring peace between Arab states and Israel helps reflect on Arild Underdal and Oran R. Young’s leadership typologies. Distinguishing between coercive leadership based on the incentives and sanctions that robust capabilities make possible and instrumental leadership focused more on talking, skilled mediation, and policy innovation is useful. However, this US mediation demonstrates that the two are not wholly distinct as previously suggested. The narrative of US efforts from Richard M Nixon to William J Clinton, including 22 cases of US involvement in Arab–Israeli mediation, suggests successful US mediation has been based on four factors. US involvement has led to breakthroughs when the US administration was highly engaged and kept at the problem after an initial diplomatic setback; benefitted from an exogenous event; managed that event to the US advantage; and dealt with strong Arab and Israeli partners.
Imperializing Norden
Authors: Neumann Iver B
Published: January 2014

The two pre-Napoleonic Nordic polities are best understood as empires. Drawing on recent analytical and historical scholarship on empires, I argue that 17th and 18th century Denmark, on which the piece concentrates, was very much akin to the other European empires existing at the time. Read in this light, national identities within the fragments of the empire appear similar. Nationalisms are all shaped directly on the Danish model, having at the same time Denmark as their constitutive cultural other. The introduction notes that, where all European imperial experiences are concerned, overseas territories had the most wounds inflicted upon them. We would not know this if we considered Faroese, Icelandic and Norwegian nationalism in isolation. These polities, Norway in particular, participated in and benefited from the colonial policies of the empire. This notwithstanding, their national identities insist that these nations were on the receiving – as opposed to the imposing – end of imperialism. This is a historically unwarranted and ethically problematic stance requiring further discussion.