bluuebunny/crossref_metadata_2025 huggingface dataset:
Reliability of SAC 305 Solder Interconnects on Double-Sided Flexible Printed Circuit Board Using X-Ray Micro-CT
Authors: Lall Pradeep , Goyal Kartik
Published: October 2017

Flexible electronics provide new design options not afforded by rigid electronics in a variety of applications including wearable electronics, robotics and automotive systems. However, the processes for the manufacturing of complex electronic assemblies using fine-pitch components are not as well developed as those for rigid electronics. The lack of structural rigidity of flexible printed circuit cards requires attention to assembly configuration for double-sided flexible assemblies. In addition, mechanisms are needed to compensate for the deformation and warpage of the flexible substrate and components during assembly. In this paper, the stresses in solder joints of double-sided flexible assemblies have been measured during thermal excursions using x-ray micro-computed tomography in conjunction with digital volume correlation. The method allows for non-invasive measurement and does not require cross-sectioning of the part for the purpose of deformation and strain measurement. In addition, the measurements are not limited to the joints in the line of sight. The three-dimensional measurements of deformation and strain have been visualized on the geometry of the solder joints in the package. Digital volume correlation (DVC) method has been used to find the displacements and strains in interconnects of operational electronics. The x-ray microscopic computed tomography (μCT) system has been used to generate the 16 bit digital volume data. The x-ray detector has ability to image the x-ray attenuation of x-rays through the object. Reliability testing of SAC 305 solder interconnects has been performed on double-sided flexible circuit board using x-ray μCT by heating the package to 100°C. The flexible circuit board used in this experiment is of BGA 256-144 combination, two packages, A-PBGA256-1.0mm-17mm and A-CABGA144-1.0mm-13mm.

A 3D printed fixture has also been used to support the flexible board and keep it flat while in the CT scan machine. The reference and deformed scans are then re-constructed 3D using Volume Graphics, and Digital Volume Correlation performed using MATLAB modules. Reliability of double-sided flexible printed circuit boards will be discussed and any crack, defects, or deformation in the solder interconnectivity which might occur while heating the package on flexible board is presented. The solder joint strains during thermal excursions are also compared between the flexible and rigid printed circuit assemblies.
Correlation of Disk Topography Waves With Nanometer Scale Lubricant Moguls
Authors: Ovcharenko Andrey , Karis Tom , Peng Jih-Ping
Published: October 2017

Magnetic recording disk carbon overcoats are lubricated with nanometer thick films of perfluoropolyether lubricant. It is well-known that lubricant thickness redistribution takes place due to air shear stress oscillation at air bearing resonant frequencies and also due to shear stress oscillation induced by disk topography waves on test tracks. We extended this work to demonstrate correlation between surface topography and lubricant redistribution on whole disk surfaces. Lubricant moguls are shown to form over regions of the disk surface which have topography waves that are half the slider length, and the lubricant thickness peak is out of phase down track from the topography peak height. There is a critical relative humidity above 20% beyond which moguls are readily formed by the slider flying at 10 nm without thermal fly height control. The significance of the lubricant redistribution for drive magnetic performance has long been the subject of debate. These results demonstrate that lubricant thickness redistribution on the order of atomic diameters can degrade magnetic performance, and that the surface topography waves alone can degrade areal density by as much as 2%.
Airborne and Structure-Borne Transmission of High Frequency Fan Vibration in a Storage Box
Authors: Eguchi Takehiko , Asai Yohei , Ichikawa Kazuhide , Takada Miki
Published: October 2017

In this paper, contributions of airborne and structure-borne vibrations to head positioning error of a HDD at high frequencies up to 10 kHz were investigated. The L8 array test was conducted with four two-level factors about vibration isolation between fans and HDDs: A) Removing bracket, B) Attaching foam on backplane, C) Filling foam in the next column, and D) Filling foam in the upper and lower slots. The test results showed there were less interaction between airborne and structure-borne vibration. Then, we set a model of fan vibration transmission and the model parameters were determined so that errors between the estimated and measured values were minimized. As the results, it was confirmed that about 80% of the power of PES was caused by the airborne vibration at the normal case.
Effect of Laser Heating on Nanoscale Wear of DLC Thin Films in an Air Environment
Authors: Tagawa Norio , Tani Hiroshi , Koganezawa Shinji , Lu Renguo
Published: October 2017

To achieve magnetic recording densities greater than 10 Tb/in2, the head-disk interface (HDI) spacing is required to be less than 2–3 nm. Thus far, various technologies, such as heat assisted magnetic recording (HAMR), have been studied and developed to achieve such high magnetic recording densities [1]. To ensure the practical applicability of HAMR, it is important to understand the reliability of perfluoropolyether (PFPE) boundary lubricant films and carbon overcoat or diamond-like carbon (DLC) thin films used on the head slider and disk surfaces under heating conditions [2].
Effect of Molecular Weight on Lubricant Depletion in a Heat Assisted Magnetic Recording System
Authors: Pan Deng , Song Wenping
Published: October 2017

A model for studying lubricant depletion in HAMR slider/disk system was developed based on molecular dynamics simulation. We found that the lubricant molecular weight has small effect on lubricant depletion.
Molecular Dynamics Study of Lubricant Evaporation and Fragmentation in Heat-Assisted Magnetic Recording With Pulsed Laser Heating
Authors: Seo Young Woo , Rosenkranz Andreas , Morris Karcher , Talke Frank E.
Published: October 2017

Molecular dynamics simulations are performed to investigate the effect of high frequency laser heating on the thermal stability of lubricant on a disk surface. Lubricant morphology, lubricant evaporation, and lubricant fragmentation are studied as a function of laser pulse duration, power density, and frequency. The results show that lubricant depletion increases with laser pulse duration.
Deterministic and statistical characterization of rigid frame porous materials from impedance tube measurements
Authors: Niskanen M. , Groby J.-P. , Duclos A. , Dazel O. , Le Roux J. C. , Poulain N. , Huttunen T. , Lähivaara T.
Published: October 2017

A method to characterize macroscopically homogeneous rigid frame porous media from impedance tube measurements by deterministic and statistical inversion is presented. Equivalent density and bulk modulus of the samples are reconstructed with the scattering matrix formalism, and are then linked to its physical parameters via the Johnson–Champoux–Allard–Lafarge model. The model includes six parameters, namely the porosity, tortuosity, viscous and characteristic lengths, and static flow and thermal permeabilities. The parameters are estimated from the measurements in two ways. The first one is a deterministic procedure that finds the model parameters by minimizing a cost function in the least squares sense. The second approach is based on statistical inversion. It can be used to assess the validity of the least squares estimate, but also presents several advantages since it provides valuable information on the uncertainty and correlation between the parameters. Five porous samples with a range of pore properties are tested, and the pore parameter estimates given by the proposed inversion processes are compared to those given by other characterization methods. Joint parameter distributions are shown to demonstrate the correlations. Results show that the proposed methods find reliable parameter and uncertainty estimates to the six pore parameters quickly with minimal user input.
Mutations within
embCAB
Are Associated with Variable Level of Ethambutol Resistance in Mycobacterium tuberculosis Isolates from China
Authors: Sun Qing , Xiao Tong-yang , Liu Hai-can , Zhao Xiu-qin , Liu Zhi-guang , Li Ya-nan , Zeng Hao , Zhao Li-li , Wan Kang-lin
Published: October 2017

The EmbCAB proteins have been considered a target for ethambutol (EMB). Mutations in
embCAB
are known to confer most EMB resistance. However, the knowledge about the effects of
embCAB
mutations on the EMB resistance level and about the role of mutation-mutation interactions is limited in China. Here, we sequenced
embCAB
among 125
Mycobacterium tuberculosis
isolates from China and quantified their EMB MICs by testing growth at 10 concentrations. Furthermore, a multivariate regression model was established to assess the effects of both individual mutations and multiple mutations. Our results revealed that in China, 82.6% of EMB-resistant isolates (71/86 isolates) harbored at least one mutation within
embCAB
. Most of the mutations were located in the
embB
and
embA
upstream region. Several individual mutations and multiple mutations within this region contributed to the different levels of EMB resistance. Their effects were statistically significant. Additionally, there was an association between high-level EMB resistance and multiple mutations.
Association between a Suppressive Combined Antiretroviral Therapy Containing Maraviroc and the Hepatitis B Virus Vaccine Response
Authors: Herrero-Fernández Inés , Pacheco Yolanda M. , Genebat Miguel , Rodriguez-Méndez María del Mar , Lozano María del Carmen , Polaino María José , Rosado-Sánchez Isaac , Tarancón-Diez Laura , Muñoz-Fernández María Ángeles , Ruiz-Mateos Ezequiel , Leal Manuel
Published: October 2017

The response to the HBV vaccine in HIV-infected patients is deficient. Our aim was to analyze whether a suppressive combined antiretroviral treatment (cART) containing maraviroc (MVC-cART) was associated with a better response to HBV vaccine. Fifty-seven patients on suppressor cART were administered the HBV vaccine. The final response, the early response, and the maintenance of the response were assessed. An anti-HBs titer of >10 mIU/ml was considered a positive response. A subgroup of subjects was simultaneously vaccinated against hepatitis A virus (HAV). Lineal regression analyses were performed to determine demographic, clinical, and immunological factors associated with the anti-HBs titer. Vaccine response was achieved in 90% of the subjects. After 1 year, 81% maintained protective titers. Only simultaneous HAV vaccination was independently associated with the magnitude of the response in anti-HBs titers, with a
P
value of 0.045 and a regression coefficient (B) [95% confident interval (CI)] of 236 [5 to 468]. In subjects ≤50 years old (
n
= 42), MVC-cART was independently associated with the magnitude of the response (
P
= 0.009; B [95% CI], 297 [79 to 516]) together with previous vaccination and simultaneous HAV vaccination. High rates of HBV vaccine response can be achieved by revaccination, simultaneous HAV vaccination, and administration of cARTs including MVC. MVC may be considered for future vaccination protocols in patients on suppressive cART.
Plasticity of the Pyruvate Node Modulates Hydrogen Peroxide Production and Acid Tolerance in Multiple Oral Streptococci
Authors: Cheng Xingqun , Redanz Sylvio , Cullin Nyssa , Zhou Xuedong , Xu Xin , Joshi Vrushali , Koley Dipankar , Merritt Justin , Kreth Jens
Published: October 2017

Commensal
Streptococcus sanguinis
and
Streptococcus gordonii
are pioneer oral biofilm colonizers. Characteristic for both is the SpxB-dependent production of H
2
O
2
, which is crucial for inhibiting competing biofilm members, especially the cariogenic species
Streptococcus mutans
. H
2
O
2
production is strongly affected by environmental conditions, but few mechanisms are known. Dental plaque pH is one of the key parameters dictating dental plaque ecology and ultimately oral health status. Therefore, the objective of the current study was to characterize the effects of environmental pH on H
2
O
2
production by
S. sanguinis
and
S. gordonii
.
S. sanguinis
H
2
O
2
production was not found to be affected by moderate changes in environmental pH, whereas
S. gordonii
H
2
O
2
production declined markedly in response to lower pH. Further investigation into the pyruvate node, the central metabolic switch modulating H
2
O
2
or lactic acid production, revealed increased lactic acid levels for
S. gordonii
at pH 6. The bias for lactic acid production at pH 6 resulted in concomitant improvement in the survival of
S. gordonii
at low pH and seems to constitute part of the acid tolerance response of
S. gordonii
. Differential responses to pH similarly affect other oral streptococcal species, suggesting that the observed results are part of a larger phenomenon linking environmental pH, central metabolism, and the capacity to produce antagonistic amounts of H
2
O
2
.

IMPORTANCE
Oral biofilms are subject to frequent and dramatic changes in pH.
S. sanguinis
and
S. gordonii
can compete with caries- and periodontitis-associated pathogens by generating H
2
O
2
. Therefore, it is crucial to understand how
S. sanguinis
and
S. gordonii
adapt to low pH and maintain their competitiveness under acid stress. The present study provides evidence that certain oral bacteria respond to environmental pH changes by tuning their metabolic output in favor of lactic acid production, to increase their acid survival, while others maintain their H
2
O
2
production at a constant level. The differential control of H
2
O
2
production provides important insights into the role of environmental conditions for growth competition of the oral flora.
Full-Genome Characterization of Simian T-Cell Leukemia Virus Type 1 Subtype b from a Wild-Born Captive
Gorilla gorilla gorilla
with T-Cell Lymphoma
Authors: Ayouba Ahidjo , Michem Annelies , Peeters Martine , Vercammen Francis
Published: October 2017

There are four lineages of primate T-cell lymphocytic viruses (human T-cell lymphocytic virus [HTLV]/simian T-cell lymphocytic virus [STLV]), which are further divided into subtypes. To date, there is only one full-length HTLV-1 subtype b genome available. Here, we report the genome of a new STLV-1 subtype b from a 43-year-old male gorilla with T-cell lymphoma.
Complete Genome Sequence of
Kluyvera intestini
sp. nov., Isolated from the Stomach of a Patient with Gastric Cancer
Authors: Tetz George , Vecherkovskaya Maria , Zappile Paul , Dolgalev Igor , Tsirigos Aristotelis , Heguy Adriana , Tetz Victor
Published: October 2017

We report here an update to the draft genome sequence of
Kluyvera intestini
sp. nov. strain GT-16, generated using MinION long-read sequencing technology. The complete genome sequence of the human-derived strain GT-16 measured 5,768,848 bp. An improved high-quality complete genome sequence provides insights into the mobility potential of resistance genes in this species.
Acquisition of the Phosphate Transporter NptA Enhances Staphylococcus aureus Pathogenesis by Improving Phosphate Uptake in Divergent Environments
Authors: Kelliher Jessica L. , Radin Jana N. , Grim Kyle P. , Párraga Solórzano Paola K. , Degnan Patrick H. , Kehl-Fie Thomas E.
Published: October 2017

During infection, pathogens must obtain all inorganic nutrients, such as phosphate, from the host. Despite the essentiality of phosphate for all forms of life, how
Staphylococcus aureus
obtains this nutrient during infection is unknown. Differing from
Escherichia coli
, the paradigm for bacterial phosphate acquisition, which has two inorganic phosphate (P
i
) importers, genomic analysis suggested that
S. aureus
possesses three distinct P
i
transporters: PstSCAB, PitA, and NptA. While
pitA
and
nptA
are expressed in phosphate-replete media, expression of all three transporters is induced by phosphate limitation. The loss of a single transporter did not affect
S. aureus
. However, disruption of any two systems significantly reduced P
i
accumulation and growth in divergent environments. These findings indicate that PstSCAB, PitA, and NptA have overlapping but nonredundant functions, thus expanding the environments in which
S. aureus
can successfully obtain P
i
. Consistent with this idea, in a systemic mouse model of disease, loss of any one transporter did not decrease staphylococcal virulence. However, loss of NptA in conjunction with either PstSCAB or PitA significantly reduced the ability of
S. aureus
to cause infection. These observations suggest that P
i
acquisition via NptA is particularly important for the pathogenesis of
S. aureus
. While our analysis suggests that NptA homologs are widely distributed among bacteria, closely related less pathogenic staphylococcal species do not possess this importer. Altogether, these observations indicate that P
i
uptake by
S. aureus
differs from established models and that acquisition of a third transporter enhances the ability of the bacterium to cause infection.
Cystic Fibrosis Airway Microbiome: Overturning the Old, Opening the Way for the New
Authors: O'Toole George A.
Published: October 2017

The genetic disease cystic fibrosis (CF) is associated with chronic airway infections that are a proximal cause of death in many patients with this affliction. Classic microbiology studies focusing on canonical pathogens resulted in the development of a common set of views regarding the nature of the airway infections associated with this disease, and these ideas have influenced everything from the way infections are treated to how clinical trials for new CF-targeted antibiotics are designed and the focus of CF-related research topics. Recent culture-independent studies have prompted us to rethink, and in some cases discard, some of these long-held views. In this piece, I argue that an updated view of the complicated chronic infections associated with CF, thanks in large part to culture-independent studies of sputum and bronchoalveolar lavage fluid samples, should be leveraged to develop new strategies to treat these recalcitrant infections.
Frequency, duration and cause of ventilator alarms on a neonatal intensive care unit
Authors: Belteki Gusztav , Morley Colin J
Published: October 2017

Objective

To investigate the frequency and cause of neonatal ventilator alarms. Neonatal ventilators frequently alarm and also disturb babies, parents and nurses. If frequent they may cause alarm fatigue and be ignored. The number, frequency and details of neonatal ventilator alarms are unreported.

Methods

We developed programs for retrieving and analysing ventilator data each second on alarms and ventilation parameters from 46 babies ventilated with Dräger Babylog VN500 ventilators using various modes.

Results

A mean of 60 hours was recorded per baby. Over 116 days, 27 751 alarms occurred. On average, that was 603 per baby and 10 per hour. Median (IQR) alarm duration was 10 (4–21) s. Type, frequency and duration varied between infants. Some babies had >10% of their time with alarms. Eight alarm types caused ~99% of all alarms. Three alarms, ‘MV high limit’ and ‘respiratory rate >high limit’, caused 46.6%, often due to inappropriate settings. 49.9% were due to a low expired tidal volume during volume guarantee ventilation, often due to the maximum pressure being set too low. 26 106 (94.1%) of all alarms lasted <1 min. However, 86 alarms lasted >10 min and 16 alarms >1 hour. Similar alarms were frequently clustered, sometimes >100/hour.

Conclusions

Frequent ventilator alarms are caused by physiological variability in the respiratory rate or minute volume, inappropriate alarm limits or too low maximum peak inflating pressure during volume-targeted ventilation. While most alarms were very short, sometimes alarms were ignored by neonatal intensive care unit staff for long periods.
Carrier envelope phase measurement of multi-cycle mid-infrared field and its application on attosecond pulse generation
Authors: Feng Liqiang , Li Wenliang
Published: October 2017

A method for the carrier envelope phase (CEP) measurement of the multi-cycle mid-infrared field has been theoretically presented by using the CEP dependence of the harmonic cutoffs. It shows that by properly adding a CEP-known few-cycle near-infrared pulse to the multi-cycle mid-infrared field, the CEP dependence of the harmonic cutoffs from the combined field become much more distinct in comparison with those from the single mid-infrared field, which provides a route to a new CEP measurement technique. Further, by properly controlling the combined field, three supercontinua of 230, 242, and 266 eV with less modulation can be obtained. Finally, by selecting the generated harmonics, a series of sub-35 as pulses in the X-rays region can be produced.
Comments on the Langmuir probe measurements of radio-frequency capacitive argon–hydrogen mixture discharge at low pressure
Authors: Tanışlı Murat , Şahi̇n Nesli̇han , Demi̇r Süleyman
Published: October 2017

In this paper, the current–voltage graphs of discharge in the chamber of capacitive coupled radio frequency (CCRF) at low pressure were presented for Langmuir probe. The Langmuir probe measurements for estimating the electron density and temperature in capacitive coupled discharges at low pressures were presented and the electron temperatures of the Ar–H2 mixture discharge generated at different conditions were reported using the Langmuir probe. The focus of this study is that the CCRF discharge can be determined and explained using the characteristics of plasma by means of Langmuir probe measurements for the different hydrogen rates in Ar–H2 mixture discharge. The measurement results of Langmuir probe gave values around 1015 m−3 for the electron density. The floating potential depended on the electronegative gas amount. It was found that the increase of hydrogen gas amount in the mixture discharge caused the decrease of the floating potential. Also, a decrease in the argon (Ar) metastable with the increase in hydrogen (H2) content was obtained. When the applied radio frequency (RF) power was increased, the thickness and collisionless sheath occurring at lower RF power could transform to thin sheath.
Estimation of the radon surface exhalation rate from a wall as related to that from its building material sample
Authors: Orabi M.
Published: October 2017

The calculated radon areal exhalation rate from a wall, based on the one-dimensional diffusion description by Fick’s law, is found to be different from that calculated from a building material sample based on the three-dimensional description. This paper is aimed to analytically clarify the origin of this difference and to relate the rates to each other. This allows finding the radon areal exhalation rate from a wall if that from the constructing building material sample is known. More importantly, it gives a more accurate estimation for the radon areal exhalation rate from a wall, which is required to calculate the indoor radon concentration, and accordingly to calculate the radon inhalation doses.
Abiotic stress tolerance and ABA responses of transgenic Glycine max plants with modulated RACK1 expression
Authors: Zheng Wen-Na , Li Da-Hong , Chen Fu-Jia , Liu Xi-Ping , Li Hong-Yan
Published: October 2017

The receptor for activated C kinase 1 (RACK1) belongs to a protein subfamily that contains a tryptophan-aspartic acid-domain (WD) repeat structure. In this study, a soybean RACK1 gene (GmRACK1) was cloned. The amino acid sequence of GmRACK1 had seven WD repeats, which contained typical glycine-histidine (GH) and WD dipeptides. Tissue-specific expression showed that GmRACK1 is expressed at differential levels in all examined tissues and strongly down-regulatd by abscisic acid (ABA) and abiotic stress. Subcellular localization suggested that GmRACK1 is located in the plasma membrane, cytoplasm, and nucleus. In response to drought and salt stress, the GmRACK1-RNAi lines showed significantly higher dry weight of whole plants, chlorophyll content, and survival rate of soybean seedlings than wild-type and homozygous (OE) lines. GmRACK1-RNAi plants were observed to be more sensitive to ABA-mediated seed germination and root growth. Furthermore, we found that the level of ABA and transcript levels of stress-responsive genes were clearly up-regulated under drought and salt stress conditions in GmRACK1-RNAi plants. Consistent with the accumulation of reactive oxygen species (ROS), elevated electrolyte leakage and malondialdehyde, and lower expression of ROS-scavenging genes were found in the GmRACK1-OE lines. The GmRACK RNAi lines exhibited increased tolerance to drought and salt stress compared with the wild-type and OE lines. In addition, yeast two-hybrid assays showed that GmRACK1 could interact with WNK8, eIF6, and RbohC-N. These results therefore indicate that GmRACK1 responds to drought and salt stress through ABA signaling and the regulation of cellular ROS production in plants.
Comparing Block-Based and Text-Based Programming in High School Computer Science Classrooms
Authors: Weintrop David , Wilensky Uri
Published: October 2017

The number of students taking high school computer science classes is growing. Increasingly, these students are learning with graphical, block-based programming environments either in place of or prior to traditional text-based programming languages. Despite their growing use in formal settings, relatively little empirical work has been done to understand the impacts of using block-based programming environments in high school classrooms. In this article, we present the results of a 5-week, quasi-experimental study comparing isomorphic block-based and text-based programming environments in an introductory high school programming class. The findings from this study show students in both conditions improved their scores between pre- and postassessments; however, students in the blocks condition showed greater learning gains and a higher level of interest in future computing courses. Students in the text condition viewed their programming experience as more similar to what professional programmers do and as more effective at improving their programming ability. No difference was found between students in the two conditions with respect to confidence or enjoyment. The implications of these findings with respect to pedagogy and design are discussed, along with directions for future work.
Hierarchical Optimal Control Method for Controlling Large-Scale Self-Organizing Networks
Authors: Kuze Naomi , Kominami Daichi , Kashima Kenji , Hashimoto Tomoaki , Murata Masayuki
Published: October 2017

Self-organization has the potential for high scalability, adaptability, flexibility, and robustness, which are vital features for realizing future networks. The convergence of self-organizing control, however, is slow in some practical applications in comparison with control by conventional deterministic systems using global information. It is therefore important to facilitate the convergence of self-organizing controls. Incontrolled self-organization, which introduces an external controller into self-organizing systems, the network is controlled to guide systems to a desired state. Although existing controlled self-organization schemes could achieve the same state, it is difficult for an external controller to collect information about the network and to provide control inputs to the network, especially when the network size is large. This is because the computational cost for designing the external controller and for calculating the control inputs increases rapidly as the number of nodes in the network becomes large. Therefore, we partition a network into several sub-networks and introduce two types of controllers, a central controller and several sub-controllers that control the network in a hierarchical manner. In this study, we propose a hierarchical optimal feedback mechanism for self-organizing systems and apply this mechanism to potential-based self-organizing routing. Simulation results show that the proposed mechanism improves the convergence speed of potential-field construction (i.e., route construction) up to 10.6-fold with low computational and communication costs.
Eunomia
Authors: Wang Xin , Zhang Weihua , Wang Zhaoguo , Wei Ziyun , Chen Haibo , Zhao Wenyun
Published: October 2017

While hardware transactional memory (HTM) has recently been adopted to construct efficient concurrent search tree structures, such designs fail to deliver scalable performance under contention. In this paper, we first conduct a detailed analysis on an HTM-based concurrent B+Tree, which uncovers several reasons for excessive HTM aborts induced by both false and true conflicts under contention. Based on the analysis, we advocate Eunomia, a design pattern for search trees which contains several principles to reduce HTM aborts, including splitting HTM regions with version-based concurrency control to reduce HTM working sets, partitioned data layout to reduce false conflicts, proactively detecting and avoiding true conflicts, and adaptive concurrency control. To validate their effectiveness, we apply such designs to construct a scalable concurrent B+Tree using HTM. Evaluation using key-value store benchmarks on a 20-core HTM-capable multi-core machine shows that Eunomia leads to 5X-11X speedup under high contention, while incurring small overhead under low contention.
Tapir
Authors: Schardl Tao B. , Moses William S. , Leiserson Charles E.
Published: October 2017

This paper explores how fork-join parallelism, as supported by concurrency platforms such as Cilk and OpenMP, can be embedded into a compiler's intermediate representation (IR). Mainstream compilers typically treat parallel linguistic constructs as syntactic sugar for function calls into a parallel runtime. These calls prevent the compiler from performing optimizations across parallel control constructs. Remedying this situation is generally thought to require an extensive reworking of compiler analyses and code transformations to handle parallel semantics.

Tapir is a compiler IR that represents logically parallel tasks asymmetrically in the program's control flow graph. Tapir allows the compiler to optimize across parallel control constructs with only minor changes to its existing analyses and code transformations. To prototype Tapir in the LLVM compiler, for example, we added or modified about 6000 lines of LLVM's 4-million-line codebase. Tapir enables LLVM's existing compiler optimizations for serial code -- including loop-invariant-code motion, common-subexpression elimination, and tail-recursion elimination -- to work with parallel control constructs such as spawning and parallel loops. Tapir also supports parallel optimizations such as loop scheduling.
A Multicore Path to Connectomics-on-Demand
Authors: Matveev Alexander , Meirovitch Yaron , Saribekyan Hayk , Jakubiuk Wiktor , Kaler Tim , Odor Gergely , Budden David , Zlateski Aleksandar , Shavit Nir
Published: October 2017

The current design trend in large scale machine learning is to use distributed clusters of CPUs and GPUs with MapReduce-style programming. Some have been led to believe that this type of horizontal scaling can reduce or even eliminate the need for traditional algorithm development, careful parallelization, and performance engineering. This paper is a case study showing the contrary: that the benefits of algorithms, parallelization, and performance engineering, can sometimes be so vast that it is possible to solve "cluster-scale" problems on a single commodity multicore machine.

Connectomics is an emerging area of neurobiology that uses cutting edge machine learning and image processing to extract brain connectivity graphs from electron microscopy images. It has long been assumed that the processing of connectomics data will require mass storage, farms of CPU/GPUs, and will take months (if not years) of processing time. We present a high-throughput connectomics-on-demand system that runs on a multicore machine with less than 100 cores and extracts connectomes at the terabyte per hour pace of modern electron microscopes.
An Efficient Abortable-locking Protocol for Multi-level NUMA Systems
Authors: Chabbi Milind , Amer Abdelhalim , Wen Shasha , Liu Xu
Published: October 2017

The popularity of Non-Uniform Memory Access (NUMA) architectures has led to numerous locality-preserving hierarchical lock designs, such as HCLH, HMCS, and cohort locks. Locality-preserving locks trade fairness for higher throughput. Hence, some instances of acquisitions can incur long latencies, which may be intolerable for certain applications. Few locks admit a waiting thread to abandon its protocol on a timeout. State-of-the-art abortable locks are not fully locality aware, introduce high overheads, and unsuitable for frequent aborts. Enhancing locality-aware locks with lightweight timeout capability is critical for their adoption. In this paper, we design and evaluate the HMCS-T lock, a Hierarchical MCS (HMCS) lock variant that admits a timeout. HMCS-T maintains the locality benefits of HMCS while ensuring aborts to be lightweight. HMCS-T offers the progress guarantee missing in most abortable queuing locks. Our evaluations show that HMCS-T offers the timeout feature at a moderate overhead over its HMCS analog. HMCS-T, used in an MPI runtime lock, mitigated the poor scalability of an MPI+OpenMP BFS code and resulted in 4.3x superior scaling.
Chinese Herbal Medicine as an Adjunctive Therapy Ameliorated the Incidence of Chronic Hepatitis in Patients with Breast Cancer: A Nationwide Population‐Based Cohort Study
Authors: Huang Kuo-Chin , Yen Hung-Rong , Chiang Jen-Huai , Su Yuan-Chih , Sun Mao-Feng , Chang Hen-Hong , Huang Sheng-Teng
Published: October 2017

We conducted a National Health Insurance Research Database‐based Taiwanese nationwide population‐based cohort study to evaluate whether Chinese herbal medicine (CHM) treatment decreased the incidence of chronic hepatitis in breast cancer patients receiving chemotherapy and/or radiotherapy. A total of 81171 patients were diagnosed with breast cancer within the defined study period. After randomly equal matching, data from 13856 patients were analyzed. Hazard ratios of incidence rate of chronic hepatitis were used to determine the influence and therapeutic potential of CHM in patients with breast cancer. The patients with breast cancer receiving CHM treatment exhibited a significantly decreased incidence rate of chronic hepatitis even across the stratification of age, CCI score, and treatments. The cumulative incidence of chronic hepatitis for a period of seven years after initial breast cancer diagnosis was also reduced in the patients receiving CHM treatment. The ten most commonly used single herbs and formulas were effective in protecting liver function in patients with breast cancer, where Hedyotis diffusa and Jia‐Wei‐Xiao‐Yao‐San were the most commonly used herbal agents. In conclusion, our study provided information that western medicine therapy combined with CHM as an adjuvant modality may have a significant impact on liver protection in patients with breast cancer.
Bufei Yishen Granules Combined with Acupoint Sticking Therapy Suppress Inflammation in Chronic Obstructive Pulmonary Disease Rats: Via JNK/p38 Signaling Pathway
Authors: Tian Yange , Li Ya , Li Jiansheng , Feng Suxiang , Li Suyun , Mao Jing , Xie Yang , Liu Xuefang , Dong Haoran , Zheng Wanchun , Wang Minghang
Published: October 2017

The present study was initiated to explore the mechanism of the effects of Bufei Yishen granules combined with acupoint sticking therapy (Shu‐Fei Tie) on inflammation regulated by c‐Jun N‐terminal kinase (JNK) and p38 MAPK signaling in COPD rats. Seventy‐two rats were divided into healthy control (Control), Model, Bufei Yishen (BY), acupoint sticking (AS), Bufei Yishen + acupoint sticking (BY + AS), and aminophylline (APL) groups (n = 12 each). COPD rats were exposed to cigarette smoke and bacteria and were given the various treatments from weeks 9 through 20; all animals were sacrificed at the end of week 20. MCP‐1, IL‐2, IL‐6, and IL‐10 concentrations in BALF and lung tissue as well as JNK and p38 mRNA and protein levels in lung were measured. The results showed that all the four treatment protocols (BY, AS, BY + AS, and APL) markedly reduced the concentrations of IL‐2, IL‐6, and MCP‐1 and levels of JNK and p38 MAPK mRNA, and the effects of Bufei Yishen granules combined with acupoint sticking therapy were better than acupoint sticking therapy only and aminophylline. In conclusion, the favorable effect of Bufei Yishen granules combined with Shu‐Fei Tie may be due to decreased inflammation through regulation of the JNK/p38 signaling pathways.
Usability Evaluation Approach of Educational Resources Software Using Mixed Intelligent Optimization
Authors: Sun Jiaze
Published: October 2017

Aiming at the problems of strong subjectivity and uncertain fuzziness of attribute weights in the software usability evaluation approach, an evaluation approach based on mixed intelligent optimization was proposed, which combines subjective and objective methods to measure software usability for educational resources software. Firstly, the usability evaluation index system of educational resources software was established, and the basic probability assignment was generated by the interval method from the historical sample data. Then the weight optimization problem was adapted to the smooth optimization problem by the maximum entropy function method, and the hybrid social cognitive optimization (HSCO) algorithm was introduced to solve the optimal weights of evidence. Finally, the software usability level was fused by DS evidence theory. The experimental results show that the educational resources software usability evaluation approach can objectively and truly reflect the usability of the software. It provides an efficient way to evaluate the usability of the software.
Erdheim-Chester Disease with No Skeletal Bone Involvement and Massive Weight Loss
Authors: Salama Hind , Kojan Suleiman , Abdulrahman Shaima , Azzumeea Fahad , Alhejazi Ayman
Published: October 2017

Erdheim-Chester disease (ECD) is a rare type of non-Langerhans cell histiocytosis, with only 550 cases reported worldwide. ECD is characterized by diffuse histiocytic infiltration of multiorgans. The age of presentation of this disease is typically between 40 and 70 years. Bone disease is the most common symptom, as unique radiological findings of long bone sclerosis occur in 96% of cases. Furthermore, BRAF V600E mutation is detected in 60% of ECD cases. In this manuscript, we are describing a unique case of ECD; the patient is younger than most reported cases and has no bone pain or any skeletal involvement. This patient has unintentionally lost about 50% of his body mass and is suffering from progressive cerebellar manifestations with radiological evidence of cerebellar atrophy, in contrast to the usual ECD manifestation of cerebellar infiltration. In addition, the patient has cardiac, retroperitoneal, and perinephric involvement, but he retains his sexual drive and fertility. A tissue biopsy from the retroperitoneal mass displayed typical morphological and immunohistochemical features of ECD, and BRAF V600E mutation was detected. He was treated with pegylated interferon alpha, but his disease progressed and the treatment was changed to vemurafenib to which he had an excellent response at 6 weeks.
Comparison of US Strain Elastography and Entero-MRI to Typify the Mesenteric and Bowel Wall Changes during Crohn’s Disease: A Pilot Study
Authors: Lo Re Giuseppe , Picone Dario , Vernuccio Federica , Scopelliti Laura , Di Piazza Ambra , Tudisca Chiara , Serraino Salvatore , Privitera Giambattista , Midiri Federico , Salerno Sergio , Midiri Massimo , Bartolotta Tommaso Vincenzo , Lagalla Roberto
Published: October 2017

Purpose. To evaluate and compare the mesenteric and bowel wall changes during Crohn’s disease (CD) on ultrasonography (US) Strain Elastography (SE) and Enterography Magnetic Resonance Imaging (E-MRI). Methods. From July 2014 to September 2016, 35 patients with ileocolonoscopy diagnosis of CD were prospectively examined with E-MRI and in the same time with US and SE. Results. A total of 41 affected bowel segments and 35 unaffected bowel segments in 35 patients were evaluated. US-SE color-scale coding showed a blue color pattern in the fibrotic mesentery and bowel wall in 15 patients and a green color pattern in the edematous ones in 20 patients. The signal of the bowel wall and mesenteric fat was iso/hypointense on T2-weighted sequence in the fibrotic pattern (23/35 and 12/35 patients) and hyperintense in the edematous pattern (12/35 and 23/35 patients). Mean ADC values were, respectively, 2,58±0,33 × 10−3 for the fibrotic mesentery and 2,14±0,28 × 10−3 for edematous one. There was a statistical correlation between US-SE color-scale and T2 signal intensity and between the US-SE color-scale and ADC maps. Conclusions. US-SE, ADC, and signal intensity on T2-weighted sequences on MR prove to be useful tools for the evaluation of CD pattern.
Migraine and Complex Regional Pain Syndrome: A Case-Referent Clinical Study
Authors: Woldeamanuel Yohannes W. , Cooley Corinne , Foley-Saldena Katharine , Cowan Robert P.
Published: October 2017

We studied clinical phenotype differences between migraineurs with CRPS (Mig + CRPS) and those without (Mig − CRPS). Mig + CRPS cases and Mig − CRPS referents aged ≥18 years were enrolled. Diagnosis was made in accordance with International Classification of Headache Disorders-3 beta (ICHD-3 beta) for migraine and Budapest Criteria for CRPS. Migraines both with and without aura were included. A total of 70 Mig + CRPS cases (13% males, mean age 48 years) and 80 Mig − CRPS referents (17% males, mean age 51 years) were included. 33% of Mig + CRPS and 38% of Mig − CRPS exhibited episodic migraine (EM) while 66% of Mig + CRPS and 62% of Mig − CRPS had chronic migraine (CM) (OR = 0.98, CI 0.36, 2.67). Median duration of CRPS was 3 years among EM + CRPS and 6 years among CM + CRPS cohort (p<0.02). Mig + CRPS (57%) carried higher psychological and medical comorbidities compared to Mig − CRPS (6%) (OR 16.7, CI 10.2, 23.6). Higher migraine frequency was associated with longer CRPS duration. Migraineurs who developed CRPS had higher prevalence of psychological and medical disorders. Alleviating migraineurs’ psychological and medical comorbidities may help lower CRPS occurrence.
Thermometric Titration for Rapid Determination of Trace Water in Jet Fuel
Authors: Hu Jian-Qiang , Zhang Jian-Jian , Yang Shi-Zhao , Xin Yong-Liang , Guo Li , Yao Ting
Published: October 2017

Water content in jet fuels is detected by thermometric titration (TMT), and the optimal detected system is 2,2-dimethoxypropane as titrant, cyclohexane and isopropanol as titration solvents, and methanesulfonic acid as catalyst in this method. The amounts of oil, concentration and delivery rate of titrant, volumes, and the reliability and accuracy of thermometric titration were emphasized. The results show that the accuracy, validity, and reliability of TMT are excellent by different indicated spiked water contents. The obtained results between TMT and Karl Fischer titration have been proven to be in accord. But, the duration of titration merely spends 3–5 min in the whole process, greatly shortening the detected time. Therefore, rapid and accurate determination of trace water in a jet fuel can be realized by TMT.
Objective Endoscopic Measurements of Central Airway Stenosis: A Pilot Study
Authors: Gil Debora , Ortiz Rosa Maria , Sánchez Carles , Rosell Antoni ,   on behalf of the SENSA team
Published: October 2017

Background: Endoscopic estimation of the degree of stenosis in central airway obstruction is subjective and highly variable. Objective: To determine the benefits of using SENSA (System for Endoscopic Stenosis Assessment), an image-based computational software, for obtaining objective stenosis index (SI) measurements among a group of expert bronchoscopists and general pulmonologists. Methods: A total of 7 expert bronchoscopists and 7 general pulmonologists were enrolled to validate SENSA usage. The SI obtained by the physicians and by SENSA were compared with a reference SI to set their precision in SI computation. We used SENSA to efficiently obtain this reference SI in 11 selected cases of benign stenosis. A Web platform with three user-friendly microtasks was designed to gather the data. The users had to visually estimate the SI from videos with and without contours of the normal and the obstructed area provided by SENSA. The users were able to modify the SENSA contours to define the reference SI using morphometric bronchoscopy. Results: Visual SI estimation accuracy was associated with neither bronchoscopic experience (p = 0.71) nor the contours of the normal and the obstructed area provided by the system (p = 0.13). The precision of the SI by SENSA was 97.7% (95% CI: 92.4-103.7), which is significantly better than the precision of the SI by visual estimation (p < 0.001), with an improvement by at least 15%. Conclusion: SENSA provides objective SI measurements with a precision of up to 99.5%, which can be calculated from any bronchoscope using an affordable scalable interface. Providing normal and obstructed contours on bronchoscopic videos does not improve physicians' visual estimation of the SI.
Hepatocyte Nuclear Factor 1α-Mutated Hepatocellular Adenomas: An Atypical Presentation
Authors: de Sousa Camila Maria Neves , Gadelha Patricia Maria Miranda , Cartaxo Rafaella de Sousa , Pedrosa George Washington Holanda , Honorio Rodrigo Schuler , Lima José Milton de Castro , Coelho Gustavo Rêgo , Coelho Clovis Rêgo
Published: October 2017

Hepatocellular adenomas (HCAs) are rare benign monoclonal hepatic tumors that commonly occur in females (3–4 per 100,000 women) due to the use of oral contraceptives, its primary risk factor. Recently, HCAs have been classified into 4 distinct subtypes according to genotypic and phenotypic characteristics and clinical features: inflammatory HCA (40–50%), which are hypervascular with marked peliosis and a tendency to bleed; hepatocyte nuclear factor 1α (HNF1A)-mutated HCA (H-HCA, 30–40%) that are diffusely steatotic and rarely undergo malignant transformation; β-catenin activated HCA (10–15%), which frequently undergo malignant transformation and may seem hepatocellular carcinoma on imaging; and unclassified HCA (10–25%). In this study, we report the case of a 23-year-old female oral contraceptive user with H-HCA. Usually, H-HCA is considered to be nonsevere in most cases and often requires outpatient follow-up. However, in this case, the injury had substantially increased in volume and evolved with a major bleeding frame, which was an unusual finding for this subtype of adenoma. The therapeutic used for this patient was a laparoscopic left hepatic segmentectomy. Thus, the choice of treatment to be performed in a patient with H-HCA can depend on the tumor size (>5 cm), the outcome of previous bleeding, and the risk of bleeding recurrence.
Hypocalcemia after Denosumab in a Pulmonary Hypertension Patient Receiving Epoprostenol
Authors: De Muynck Benedicte , Leys Mathias , Cuypers Joke , Vanderschueren Dirk , Delcroix Marion , Belge Catharina
Published: October 2017

We report the case of a 50-year-old woman with anorexigen-induced pulmonary arterial hypertension treated with epoprostenol, who presented with Trousseau’s sign, leading to the diagnosis of severe hypocalcemia for which substitution was started (initially orally, followed by intravenous substitution). After further analysis, we assume that epoprostenol-induced diarrhea caused malabsorption (as other reasons were excluded), leading to nutritional osteomalacia with secondary hyperparathyroidism. We discovered that even more severe hypocalcemia was induced by the treatment with the anti-osteoporotic drug denosumab, which was started after the diagnosis of osteoporosis on bone densitometry. In our opinion, clinicians have to be aware that in patients with malabsorption, antiresorptive therapy can induce dangerous and even life-threatening hypocalcemia, even in patients with normal renal function.