bluuebunny/crossref_metadata_2025 huggingface dataset:
Computational Prediction of Muscle Moments During ARED Squat Exercise on the International Space Station
Authors: Fregly Benjamin J. , Fregly Christopher D. , Kim Brandon T.
Published: October 2015

Prevention of muscle atrophy caused by reduced mechanical loading in microgravity conditions remains a challenge for long-duration spaceflight. To combat leg muscle atrophy, astronauts on the International Space Station (ISS) often perform squat exercise using the Advanced Resistive Exercise Device (ARED). While the ARED is effective at building muscle strength and volume on Earth, NASA researchers do not know how closely ARED squat exercise on the ISS replicates Earth-level squat muscle moments, or how small variations in exercise form affect muscle loading. This study used dynamic simulations of ARED squat exercise on the ISS to address these two questions. A multibody dynamic model of the complete astronaut-ARED system was constructed in OpenSim. With the ARED base locked to ground and gravity set to 9.81 m/s2, we validated the model by reproducing muscle moments, ground reaction forces, and foot center of pressure (CoP) positions for ARED squat exercise on Earth. With the ARED base free to move relative to the ISS and gravity set to zero, we then used the validated model to simulate ARED squat exercise on the ISS for a reference squat motion and eight altered squat motions involving changes in anterior–posterior (AP) foot or CoP position on the ARED footplate. The reference squat motion closely reproduced Earth-level muscle moments for all joints except the ankle. For the altered squat motions, changing the foot position was more effective at altering muscle moments than was changing the CoP position. All CoP adjustments introduced an undesirable shear foot reaction force that could cause the feet to slip on the ARED footplate, while some foot and CoP adjustments introduced an undesirable sagittal plane foot reaction moment that would cause the astronaut to rotate off the ARED footplate without the use of some type of foot fixation. Our results provide potentially useful information for achieving desired increases or decreases in specific muscle moments during ARED squat exercise performed on the ISS.
An Automated Approach to Enhance Multiscale Signal Monitoring of Manufacturing Processes
Authors: Grasso Marco , Maria Colosimo Bianca
Published: October 2015

Multiscale signal decomposition represents an important step to enhance process monitoring results in many manufacturing applications. Empirical mode decomposition (EMD) is a data driven technique that gained an increasing interest in this framework. However, it usually yields an-over decomposition of the signal, leading to the generation of spurious and meaningless modes and the possible mixing of embedded modes. This study proposes an enhanced signal decomposition approach that synthetizes the original information content into a minimal number of relevant modes via a data-driven and automated procedure. A criterion based on the kernel estimation of density functions is proposed to estimate the dissimilarities between the intrinsic modes generated by the EMD, together with a methodology to automatically determine the optimal number of final modes. The performances of the method are demonstrated by means of simulated signals and real industrial data from a waterjet cutting application.
Design and Preliminary Evaluation of a Passive Spine Exoskeleton
Authors: Zhang Haohan , Kadrolkar Abhijit , Sup Frank C.
Published: October 2015

This paper presents a design of a passive spine exoskeleton which implements a “push–pull” external assistive strategy. The spine exoskeleton was designed for reducing the risk of back injury. It applies a pulling force on thoracic region and a pushing force on lumbar region during spine flexion/extension. The design was inspired by previous simulation work, where the results highly supported benefits of the push–pull strategy on reducing the back muscular efforts and bending moment for the sagittal spine flexion/extension. A passive physical prototype was designed and constructed to test the push–pull strategy on human subjects. Three subjects were able to repeat the identical dynamic spine flexion and extension tasks with the spine exoskeleton prototype. The surface electromyography showed a reduction of up to 24% at lumbar and 54% at thoracic level muscle for the human subjects wearing the exoskeleton suit to accomplish the same static tasks without any external assistance. The muscle force and intervertebral bending moment were estimated to be reduced by up to 479 N and 36 N · m, respectively.
Type Synthesis of 1R1T Remote Center of Motion Mechanisms Based on Pantograph Mechanisms
Authors: Long Huang , Yang Yang , Jingjing Xiao , Peng Su
Published: October 2015

The remote center of motion (RCM) mechanism is an important component of a minimally invasive surgery (MIS) robot. The feature of the RCM mechanism is that the output link can rotate around a fixed point and translate along an axis which passes the point; however, there is no revolute joint at the fixed point. The 3R1T RCM mechanism, which meets all the degrees-of-freedom (DOF) requirements of arbitrary MIS tools, can be assembled through many methods. An effective method is combining a planar closed-loop 1R1T RCM mechanism and two revolute joints. In this paper, we present an approach to construct 1R1T RCM mechanisms from pantograph mechanisms. First, pantograph mechanisms are divided into seven classifications according to the geometric transformations they represent. The concept of rigid motion tracking mechanism (RMTM) is proposed by combining two equivalent pantograph mechanisms. Then, a novel type synthesis method for 1R1T RCM mechanisms is discussed in detail, and it shows that a 1R1T RCM mechanism can be constructed by assembling an RMTM and a 1R1T mechanism. By this method, several examples are constructed.
Avoiding Early Failures in Conjugate Cam Mechanism by Means of Different Design Strategies
Authors: Català Pau , Antònia De los Santos Maria , Veciana Joaquim M. , Cardona Salvador
Published: October 2015

To solve the indetermination of forces existing in a form-closed cam mechanism formed by conjugate cams, where the contact between the cams and the follower rollers is constantly ensured by only the geometry of the elements, dynamic models that consider the elasticity of the elements must be proposed. Because the stiffness of the main elements is associated with the elasticity of the solids, tight variations in manufacturing and assembly errors modify the effective interference fit, which significantly affects the expected fatigue life of the mechanism, leading to a premature failure of the elements due to surface fatigue. Based on a real industrial application of a conjugate cam mechanism and using lumped-parameter models, the objectives of this paper are: first, to show that it is difficult to achieve a pure form-closed conjugate cam mechanism, with the expected fatigue life of the mechanism, by using only standard tolerance specifications; second, to compare the expected fatigue life and motor torque with other cam mechanism design strategies such as force-closed and the combination of force-closed and form-closed strategies, known as force-closed conjugate cam strategy. This paper based on simulation results demonstrates that this latest strategy can, thanks to a better control of the preload, easily achieve results very similar to the theoretical ones of a form-closed conjugate cam mechanism. A prototype of the mechanism of the force-closed conjugate cam strategy is also built.
Spatial Straight-Line Linkages by Factorization of Motion Polynomials
Authors: Li Zijia , Schicho Josef , Schröcker Hans-Peter
Published: October 2015

We use the recently introduced factorization of motion polynomials for constructing overconstrained spatial linkages with a straight-line trajectory. Unlike previous examples of such linkages by other authors, they are single-loop linkages and the end-effector motion is not translational. In particular, we obtain a number of linkages with four revolute and two prismatic joints and a remarkable linkage with seven revolute joints one of whose joints performs a Darboux motion.
Trajectory Planning for Micromanipulation With a Nonredundant Digital Microrobot: Shortest Path Algorithm Optimization With a Hypercube Graph Representation
Authors: Chalvet Vincent , Haddab Yassine , Lutz Philippe
Published: October 2015

Microrobotics is an ongoing study all over the world for which design is often inspired from macroscale robots. We have proposed the design of a new kind of microfabricated microrobot based on the use of binary actuators in order to generate a highly accurate and repeatable tool for positioning tasks at microscale without any sensor (with open-loop control). Our previous work consisted in the design, modeling, fabrication, and characterization of the first planar digital microrobot. In this paper, we focus on the motion planning of this robot for micromanipulation tasks. The complex motion pattern of this robot requires the use of algorithms. Graph theory is well suited for the discrete workspace generated by this robot. The comparison between several well-known trajectory-planning algorithms is done. A new graphical representation, named the hypercubic graph, is used for improving the computation speed of the algorithm. This is particularly useful for large workspace robots.
An Extensible Continuum Robot With Integrated Origami Parallel Modules
Authors: Zhang Ketao , Qiu Chen , Dai Jian S.
Published: October 2015

This paper presents a novel design of extensible continuum robots in light of origami-inspired folding techniques. The design starts from a modularized crease pattern, which consists of two triangular bases and three waterbomb bases, and generates a folding process for creating an origami waterbomb parallel structure. This further progresses to generating a compliant module with the origami parallel structure and a helical compression spring. A novel extensible continuum robot with the integrated compliant parallel modules is then proposed to imitate not only the bending motion but also the contraction of continuum creatures in nature. Mapping the origami parallel structure to an equivalent kinematic model, the motion characteristics of the origami structure are explored in terms of kinematic principles. The analysis reveals the mixed rotational and translational motion of the origami parallel module and the virtual axes for yaw and pitch motions. Following kinematics of the proposed continuum robot and features of the integrated helical spring in each module, three actuation schemes and resultant typical working phases with a tendon-driven system are presented. The design and analysis are then followed by a prototype of the extensible continuum robot with six integrated compliant modules connected in serial. The functionality of the proposed continuum robot with the origami parallel structure as its skeleton and the helical springs as the compliant backbone is validated by experimental results.
Multitransformable Leaf-Out Origami With Bistable Behavior
Authors: Yasuda Hiromi , Chen Zhisong , Yang Jinkyu
Published: October 2015

We study the kinematics of leaf-out origami and explore its potential usage as multitransformable structures without the necessity of deforming the origami's facets or modifying its crease patterns. Specifically, by changing folding/unfolding schemes, we obtain various geometrical configurations of the leaf-out origami based on the same structure. We model the folding/unfolding motions of the leaf-out origami by introducing linear torsion springs along the crease lines, and we calculate the potential energy during the shape transformation. As a result, we find that the leaf-out structure exhibits distinctive values of potential energy depending on its folded stage, and it can take multiple paths of potential energy during the transformation process. We also observe that the leaf-out structure can show bistability, enabling negative stiffness and snap-through mechanisms. These unique features can be exploited to use the leaf-out origami for engineering applications, such as space structures and architectures.
Development of Probability of Ignition Model for Ruptures of Onshore Natural Gas Transmission Pipelines
Authors: Lam Chio , Zhou Wenxing
Published: October 2015

A log-logistic probability of ignition (POI) model for ruptures of onshore natural gas transmission pipelines is proposed in this paper. The parameters of the proposed POI model are evaluated based on a total of 188 rupture incidents that occurred on onshore gas transmission pipelines in the U.S. between 2002 and 2014 as recorded in the pipeline incident database administered by the Pipeline and Hazardous Material Safety Administration (PHMSA) of the U.S. Department of Transportation. The product of the pipe internal pressure at the time of rupture and outside diameter squared is observed to be strongly correlated with POI and therefore adopted as the sole predictor in the POI model. The maximum likelihood method is employed to evaluate the model parameters. The 95% confidence interval and upper confidence bound on the POI model are also evaluated. The model is validated against an independent set of rupture incident data reported in the literature. The proposed POI model will facilitate the quantitative risk assessment of onshore natural gas transmission pipelines in the U.S.
Mode of heparin attachment to nanocrystalline hydroxyapatite affects its interaction with bone morphogenetic protein-2
Authors: Goonasekera Chandhi S. , Jack Kevin S. , Bhakta Gajadhar , Rai Bina , Luong-Van Emma , Nurcombe Victor , Cool Simon M. , Cooper-White Justin J. , Grøndahl Lisbeth
Published: October 2015

Heparin has a high affinity for bone morphogenetic protein-2 (BMP-2), which is a key growth factor in bone regeneration. The aim of this study was to investigate how the rate of release of BMP-2 was affected when adsorbed to nanosized hydroxyapatite (HAP) particles functionalized with heparin by different methods. Heparin was attached to the surface of HAP, either via adsorption or covalent coupling, via a 3-aminopropyltriethoxysilane (APTES) layer. The chemical composition of the particles was evaluated using X-ray photoelectron spectroscopy and elemental microanalysis, revealing that the heparin grafting densities achieved were dependent on the curing temperature used in the fabrication of APTES-modified HAP. Comparable amounts of heparin were attached via both covalent coupling and adsorption to the APTES-modified particles, but characterization of the particle surfaces by zeta potential and Brunauer–Emmett–Teller measurements indicated that the conformation of the heparin on the surface was dependent on the method of attachment, which in turn affected the stability of heparin on the surface. The release of BMP-2 from the particles after 7 days in phosphate-buffered saline found that 31% of the loaded BMP-2 was released from the APTES-modified particles with heparin covalently attached, compared to 16% from the APTES-modified particles with the heparin adsorbed. Moreover, when heparin was adsorbed onto pure HAP, it was found that the BMP-2 released after 7 days was 5% (similar to that from unmodified HAP). This illustrates that by altering the mode of attachment of heparin to HAP the release profile and total release of BMP-2 can be manipulated. Importantly, the BMP-2 released from all the heparin particle types was found by the SMAD 1/5/8 phosphorylation assay to be biologically active.
Luminescence imaging of water during proton‐beam irradiation for range estimation
Authors: Yamamoto Seiichi , Toshito Toshiyuki , Okumura Satoshi , Komori Masataka
Published: October 2015

Purpose:

Proton therapy has the ability to selectively deliver a dose to the target tumor, so the dose distribution should be accurately measured by a precise and efficient method. The authors found that luminescence was emitted from water during proton irradiation and conjectured that this phenomenon could be used for estimating the dose distribution.

Methods:

To achieve more accurate dose distribution, the authors set water phantoms on a table with a spot scanning proton therapy system and measured the luminescence images of these phantoms with a high‐sensitivity, cooled charge coupled device camera during proton‐beam irradiation. The authors imaged the phantoms of pure water, fluorescein solution, and an acrylic block.

Results:

The luminescence images of water phantoms taken during proton‐beam irradiation showed clear Bragg peaks, and the measured proton ranges from the images were almost the same as those obtained with an ionization chamber. Furthermore, the image of the pure‐water phantom showed almost the same distribution as the tap‐water phantom, indicating that the luminescence image was not related to impurities in the water. The luminescence image of the fluorescein solution had ∼3 times higher intensity than water, with the same proton range as that of water. The luminescence image of the acrylic phantom had a 14.5% shorter proton range than that of water; the proton range in the acrylic phantom generally matched the calculated value. The luminescence images of the tap‐water phantom during proton irradiation could be obtained in less than 2 s.

Conclusions:

Luminescence imaging during proton‐beam irradiation is promising as an effective method for range estimation in proton therapy.
The Tacoma Narrows Bridge Collapse on Film and Video
Authors: Olson Don , Hook Joseph , Doescher Russell , Wolf Steven
Published: October 2015

This month marks the 75th anniversary of the Tacoma Narrows Bridge collapse. During a gale on Nov. 7, 1940, the bridge exhibited remarkable oscillations before collapsing spectacularly (Figs. 1–5). Physicists over the years have spent a great deal of time and energy studying this event. By using open-source analysis tools and digitized footage of the disaster, physics students in both high school and college can continue in this tradition. Students can watch footage of “Galloping Gertie,” ask scientific questions about the bridge's collapse, analyze data, and draw conclusions from that analysis. Students should be encouraged to pursue their own investigations, but the question that drove our inquiry was this: When physics classes watch modern video showing the oscillations and the free fall of the bridge fragments, are these scenes sped up, slowed down, or at the correct speed compared to what was observed by the eyewitnesses on Nov. 7, 1940?
Introducing Filters and Amplifiers Using a Two-Channel Light Organ
Authors: Zavrel Erik , Sharpsteen Eric
Published: October 2015

In an era when many students carry iPods, iPhones, and iPads, physics teachers are realizing that in order to continue to inspire and convey the amazing things made possible by a few fundamental principles, they must expand laboratory coverage of electricity and circuits beyond the conventional staples of constructing series and parallel arrangements of light bulbs and confirming Kirchhoff's laws. Indeed, physics teachers are already incorporating smartphones into their laboratory activities in an effort to convey concepts in a more contemporary and relatable manner. As part of Cornell's Learning Initiative in Medicine and Bioengineering (CLIMB), we set out to design and implement an engaging curriculum to introduce high school physics students to filters and amplifiers.
Moment of Inertia by Differentiation
Authors: Rizcallah Joseph A.
Published: October 2015

The calculation of the moment of inertia of an extended body, as presented in standard introductory-level textbooks, involves the evaluation of a definite integral—an operation often not fully mastered by beginners, let alone the conceptual difficulties it presents, even to the advanced student, in understanding and setting up the integral in the first place. We here use dimensional analysis along with elementary differentiation techniques to derive the moments of inertia of various extended bodies. The suggested method does not employ integrals and, in effect, is just a disguised application of elementary ordinary differential equations.
Bouncing Poppers
Authors: Vollmer Michael , Möllmann Klaus-Peter
Published: October 2015

Toys are known to attract interest in physics and they are therefore often used in physics teaching of various topics. The present paper deals with a simple toy, the so-called “hopper popper,” which, similar to superballs, can be used when teaching mechanics. We suggest some experiments and describe the basic physics of this toy, also providing background information for teachers.
The direction of acceleration
Authors: Wilhelm Thomas , Burde Jan-Philipp , Lück Stephan
Published: October 2015

Acceleration is a physical quantity that is difficult to understand and hence its complexity is often erroneously simplified. Many students think of acceleration as equivalent to velocity, a ∼ v. For others, acceleration is a scalar quantity, which describes the change in speed Δ|v| or Δ|v|/Δt (as opposed to the change in velocity). The main difficulty with the concept of acceleration therefore lies in developing a correct understanding of its direction. The free iOS app AccelVisu supports students in acquiring a correct conception of acceleration by showing acceleration arrows directly at moving objects.
Observations of backscatter from sand and gravel seafloors between 170 and 250 kHz
Authors: Weber Thomas C. , Ward Larry G.
Published: October 2015

Interpreting observations of frequency-dependence in backscatter from the seafloor offers many challenges, either because multiple frequencies are used for different observations that will later be merged or simply because seafloor scattering models are not well-understood above 100 kHz. Hindering the understanding of these observations is the paucity of reported, calibrated acoustic measurements above 100 kHz. This manuscript seeks to help elucidate the linkages between seafloor properties and frequency-dependent seafloor backscatter by describing observations of backscatter collected from sand, gravel, and bedrock seafloors at frequencies between 170 and 250 kHz and at a grazing angle of 45°. Overall, the frequency dependence appeared weak for all seafloor types, with a slight increase in seafloor scattering strength with increasing frequency for an area with unimodal, very poorly to moderately well sorted, slightly granular to granular medium sand with significant amounts of shell debris and a slight decrease in all other locations.
Identification and characterization of essential genes in the human genome
Authors: Wang Tim , Birsoy Kıvanç , Hughes Nicholas W. , Krupczak Kevin M. , Post Yorick , Wei Jenny J. , Lander Eric S. , Sabatini David M.
Published: October 2015

Zeroing in on essential human genes

More powerful genetic techniques are helping to define the list of genes required for the life of a human cell. Two papers used the CRISPR genome editing system and a gene trap method in haploid human cells to screen for essential genes (see the Perspective by Boone and Andrews). Wang
et al.
's analysis of multiple cell lines indicates that it may be possible to find tumor-specific dependencies on particular genes. Blomen
et al.
investigate the phenomenon in which nonessential genes are required for fitness in the absence of another gene. Hence, complexity rather than robustness is the human strategy.

Science
, this issue p.
1096
and p.
1092
; see also p.
1028
Making waves: The science and politics of ocean protection
Authors: Lubchenco Jane , Grorud-Colvert Kirsten
Published: October 2015

Mature science reveals opportunities for policy progress
Draft Genome Sequences of Three Strains of Geobacillus stearothermophilus Isolated from a Milk Powder Manufacturing Plant
Authors: Burgess Sara A. , Cox Murray P. , Flint Steve H. , Lindsay Denise , Biggs Patrick J.
Published: October 2015

Three strains of
Geobacillus stearothermophilus
(designated A1, P3, and D1) were isolated from a New Zealand milk powder manufacturing plant. Here, we describe their draft genome sequences. This information provided the first genomic insights into the nature of
G. stearothermophilus
strains present in the milk powder manufacturing environment.
Complete Genome Sequence of Kocuria palustris MU14/1
Authors: Calcutt Michael J. , Foecking Mark F.
Published: October 2015

Presented here is the first completely assembled genome sequence of
Kocuria palustris
, an actinobacterial species with broad ecological distribution. The single, circular chromosome of
K. palustris
MU14/1 comprises 2,854,447 bp, has a G+C content of 70.5%, and contains a deduced gene set of 2,521 coding sequences.
Draft Genome Sequence of Lactobacillus gorillae Strain KZ01
T
, Isolated from a Western Lowland Gorilla
Authors: Tsuchida Sayaka , Nezuo Maiko , Tsukahara Masatoshi , Ogura Yoshitoshi , Hayashi Tetsuya , Ushida Kazunari
Published: October 2015

Here, we report the draft genome sequence of
Lactobacillus gorillae
strain KZ01
T
isolated from a western lowland gorilla (
Gorilla gorilla gorilla
). This genome sequence will be helpful for the comparative genomics between human and nonhuman primate-associated
Lactobacillus
.
Genome Sequences of Two Bacillus cereus Group Bacteriophages, Eyuki and AvesoBmore
Authors: Erill Ivan , Caruso Steven M.
Published: October 2015

The genomes of two double-stranded DNA (dsDNA) bacteriophages isolated on
Bacillus thuringiensis
show similarity to previously sequenced phages and provide evidence of the mosaicism of phage genomes.
Genome Sequence of Acinetobacter baumannii Strain 5021_13, Isolated from Cerebrospinal Fluid
Authors: Kumar Sunil , Patil Prashant P. , Midha Samriti , Ray Pallab , Patil Prabhu B. , Gautam Vikas
Published: October 2015

We report here the 4.1-Mb draft genome sequence of
Acinetobacter baumannii
strain 5021_13, a cerebrospinal fluid isolate from northern India. This genome information will help studies toward understanding the epidemiology and pathogenicity of this important nosocomial pathogen.
Effectiveness of hand hygiene interventions in reducing illness absence among children in educational settings: a systematic review and meta-analysis
Authors: Willmott Micky , Nicholson Alexandra , Busse Heide , MacArthur Georgina J , Brookes Sara , Campbell Rona
Published: October 2015

Objective

To undertake a systematic review and meta-analysis to establish the effectiveness of handwashing in reducing absence and/or the spread of respiratory tract (RT) and/or gastrointestinal (GI) infection among school-aged children and/or staff in educational settings.

Design

Randomised-controlled trials (RCTs).

Setting

Schools and other settings with a formal educational component in any country.

Patients

Children aged 3–11 years, and/or staff working with them.

Intervention

Interventions with a hand hygiene component.

Main outcome measures

Incidence of RT or GI infections or symptoms related to such infections; absenteeism; laboratory results of RT and/or GI infections.

Results

Eighteen cluster RCTs were identified; 13 school-based, 5 in child day care facilities or preschools. Studies were heterogeneous and had significant quality issues including small numbers of clusters and participants and inadequate randomisation. Individual study results suggest interventions may reduce children's absence, RT infection incidence and symptoms, and laboratory confirmed influenza-like illness. Evidence of impact on GI infection or symptoms was equivocal.

Conclusions

Studies are generally not well executed or reported. Despite updating existing systematic reviews and identifying new studies, evidence of the effect of hand hygiene interventions on infection incidence in educational settings is mostly equivocal but they may decrease RT infection among children. These results update and add to knowledge about this crucial public health issue in key settings with a vulnerable population. More robust, well reported cluster RCTs which learn from existing studies, are required.
A paradoxical decline: intracranial lesions in two HIV-positive patients recovering from cryptococcal meningitis
Authors: Pettersen Kenneth D , Pappas Peter G , Chin-Hong Peter , Baxi Sanjiv M
Published: October 2015

Cryptococcal immune reconstitution inflammatory syndrome (C-IRIS) is an increasingly important manifestation among patients with HIV/AIDS, especially as the use of antiretroviral therapy (ART) is expanding worldwide.Cryptococcusand associated C-IRIS are common causes of meningitis. While intracranial lesions are common in HIV/AIDS, they are rarely due to cryptococcosis or C-IRIS. We describe two cases of paradoxical C-IRIS associated with the development of intracranial cryptococcomas in HIV/AIDS. Both patients had an initial episode of cryptococcal meningitis treated with antifungal therapy. At the time, they had initiated or modified ART with subsequent evidence of immune reconstitution. Two months later, they developed aseptic meningitis with intracranial lesions. After exhaustive work ups, both patients were diagnosed with paradoxical C-IRIS and biopsy confirmed intracranial cryptococcomas. We review the important clinical, diagnostic and therapeutic features of cryptococcomas associated with C-IRIS in HIV/AIDS.
Late quadriceps tendon rupture at the donor site following cruciate ligament reconstruction using central quadriceps tendon graft
Authors: Pandey Vivek , Madi Sandesh , Joseph Amy , Acharya Kiran
Published: October 2015

Central quadriceps tendon (CQT) graft has been successfully used as a viable autograft option in cruciate ligament reconstruction of the knee. The prime emphasis in the majority of the literature is given to surgical details of quadriceps graft harvesting and outcome of cruciate ligament reconstruction. There is less discussion about donor site morbidity in CQT graft, and it is less frequent as compared to that in bone patellar tendon bone graft. We report an extremely unusual case of late quadriceps tendon rupture at the donor site following anterior cruciate ligament reconstruction using CQT graft.
Effects of krill oil on endothelial function and other cardiovascular risk factors in participants with type 2 diabetes, a randomized controlled trial
Authors: Lobraico Jessika M , DiLello Lauren C , Butler Amber D , Cordisco Marie Elena , Petrini Joann R , Ahmadi Ramin
Published: October 2015

Objective

The purpose of this trial was to evaluate the effect of krill oil supplementation, a source of ω-3 fatty acids, on cardiovascular disease risk factors and blood glucose control among participants with type 2 diabetes.

Research design and methods

A randomized, double-blind controlled cross-over trial was employed. Outcomes assessed were: endothelial function, blood lipids, glucose, glycated hemoglobin, serum antioxidant level, C peptide, and calculated Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) scores. Participants were randomized to either krill oil or olive oil supplementation for 4 weeks, underwent a 2-week washout period, and then crossed to the other supplementation for 4 weeks. All participants were then offered an additional 17 weeks of krill supplementation. Testing occurred at 3 time points: baseline, after first supplementation, and after second supplementation. Testing also occurred after an optional 17 weeks of krill oil supplementation. Difference scores were calculated for each participant in both sequences (ie, differences in outcome measures in the first and second period of the sequence). The mean and SD of the scores in the 2 sequence groups were used to test for differences between treatment effects at a significance level of p<0.05.

Results

A total of 47 participants were included in the initial cross-over study. Participants who received krill oil for 4 weeks had an improvement in their endothelial function and a reduction in blood C peptide levels and HOMA scores as compared with the olive oil. A total of 34 participants completed the additional 17-week supplementation period. When compared with their respective baseline measures, these participants had a statistically significant improvement in endothelial function and blood high-density lipoprotein (HDL).

Conclusions

Krill oil may lead to moderate improvement of cardiovascular risks, specifically endothelial dysfunction and HDL in patients with type 2 diabetes.

Trial registration number

Registered with ClinicalTrials.gov:NCT02091193.
Preferred and actual place of death in haematological malignancy
Authors: Howell D A , Wang H I , Roman E , Smith A G , Patmore R , Johnson M J , Garry A , Howard M
Published: October 2015

Objectives

Home is considered the preferred place of death for many, but patients with haematological malignancies (leukaemias, lymphomas and myeloma) die in hospital more often than those with other cancers and the reasons for this are not wholly understood. We examined preferred and actual place of death among people with these diseases.

Methods

The study is embedded within an established population-based cohort of patients with haematological malignancies. All patients diagnosed at two of the largest hospitals in the study area between May 2005 and April 2008 with acute myeloid leukaemia, diffuse large B-cell lymphoma or myeloma, who died before May 2010 were included. Data were obtained from medical records and routine linkage to national death records.

Results

323 deceased patients were included. A total of 142 (44%) had discussed their preferred place of death; 45.8% wanted to die at home, 28.2% in hospital, 16.9% in a hospice, 5.6% in a nursing home and 3.5% were undecided; 63.4% of these died in their preferred place. Compared to patients with evidence of a discussion, those without were twice as likely to have died within a month of diagnosis (14.8% vs 29.8%). Overall, 240 patients died in hospital; those without a discussion were significantly more likely to die in hospital than those who had (p≤0.0001). Of those dying in hospital, 90% and 75.8% received haematology clinical input in the 30 and 7 days before death, respectively, and 40.8% died in haematology areas.

Conclusions

Many patients discussed their preferred place of death, but a substantial proportion did not and hospital deaths were common in this latter group. There is scope to improve practice, particularly among those dying soon after diagnosis. We found evidence that some people opted to die in hospital; the extent to which this compares with other cancers is of interest.
Effects of age and hindlimb immobilization and remobilization on fast troponin T precursor mRNA alternative splicing in rat gastrocnemius muscle
Authors: Ravi Suhana , Schilder Rudolf J. , Berg Arthur S. , Kimball Scot R.
Published: October 2015

Fast skeletal muscle troponin T (TNNT3) is an important component of the skeletal muscle contractile machinery. The precursor mRNA (pre-mRNA) encoding TNNT3 is alternatively spliced, and changes in the pattern of TNNT3 splice form expression are associated with alterations in thin-filament calcium sensitivity and force production during muscle contraction and thereby regulate muscle function. Interestingly, during aging, the muscle force/cross-sectional area is reduced, suggesting that loss of mass does not completely account for the impaired muscle function that develops during the aging process. Therefore, in this study, we tested the hypothesis that age and changes in muscle loading are associated with alterations in Tnnt3 alternative splicing in the rat gastrocnemius muscle. We found that the relative abundance of several Tnnt3 splice forms varied significantly with age among 2-, 9-, and 18-month-old rats and that the pattern correlated with changes in body mass rather than muscle mass. Hindlimb immobilization for 7 days resulted in dramatic alterations in splice form relative abundance such that the pattern was similar to that observed in lighter animals. Remobilization for 7 days restored the splicing pattern toward that observed in the nonimmobilized limb, even though muscle mass had not yet begun to recover. In conclusion, the results suggest that Tnnt3 pre-mRNA alternative splicing is modulated rapidly (i.e., within days) in response to changes in the load placed on the muscle. Moreover, the results show that restoration of Tnnt3 alternative splicing to control patterns is initiated prior to an increase in muscle mass.
Cellular and viral determinants of retroviral nuclear entry
Authors: Hamid Faysal Bin , Kim Jinsun , Shin Cha-Gyun
Published: October 2015

Retroviruses must integrate their cDNA into the host genome to generate proviruses. Viral DNA–protein complexes interact with cellular proteins and produce pre-integration complexes, which carry the viral genome and cross the nuclear pore channel to enter the nucleus and integrate viral DNA into host chromosomal DNA. If the reverse transcripts fail to integrate, linear or circular DNA species such as 1- and 2-long terminal repeats are generated. Such complexes encounter numerous cellular proteins in the cytoplasm, which restrict viral infection and protect the nucleus. To overcome host cell defenses, the pathogens have evolved several evasion strategies. Viral proteins often contain nuclear localization signals, allowing entry into the nucleus. Among more than 1000 proteins identified as required for HIV infection by RNA interference screening, karyopherins, cleavage and polyadenylation specific factor 6, and nucleoporins have been predominantly studied. This review discusses current opinions about the synergistic relationship between the viral and cellular factors involved in nuclear import, with focus on the unveiled mysteries of the host–pathogen interaction, and highlights novel approaches to pinpoint therapeutic targets.
Computational investigation on thermal conductivity behavior of Al 6061–SiC–Gr hybrid metal matrix composites
Authors: Krishna S. A. Mohan , Shridhar T. N. , Krishnamurthy L.
Published: October 2015

Metal matrix composites (MMCs) are regarded to be one of the most principal classifications in composite materials. The thermal characterization of hybrid MMCs has become increasingly important in a wide range of applications. Thermal conductivity is one of the most important properties of MMCs. Since nearly all MMCs are used in various temperature ranges, measurement of thermal conductivity as a function of temperature is necessary in order to know the behavior of the material. In the present research, evaluation of thermal conductivity has been accomplished for aluminum alloy (Al) 6061, silicon carbide (SiC) and graphite (Gr) hybrid MMCs from room temperature to [Formula: see text]C. Al-based composites reinforced with SiC and Gr particles have been prepared by stir casting technique. The thermal conductivity behavior of hybrid composites with different percentage compositions of reinforcements has been investigated using laser flash technique. The results have indicated that the thermal conductivity of the different compositions of hybrid MMCs decreases by the addition of Gr with SiC and Al 6061. Few empirical models have been validated concerning with the evaluation of thermal conductivity of composites. Using the experimental values namely density, thermal conductivity, specific heat capacity and enthalpy at varying temperature ranges, computational investigation has been carried out to evaluate the thermal gradient and thermal flux.
Mr Mawson's fossils
Authors: Maisey John G.
Published: October 2015

Joseph Mawson, a nineteenth-century British railway engineer and businessman in Brazil, discovered fossils from the Cretaceous of Bahia that were described by E. D. Cope and Arthur Smith Woodward. A biographical outline of Mawson is presented. Mawson's discoveries (especially the giant coelacanth fish
Mawsonia
, named after him by ASW) are interpreted today in the light of modern geological investigations.
Mawsonia
apparently lived in fluvial, lacustrine and brackish-water habitats in western Gondwana at the time South America separated from Africa. From the Late Jurassic until the Barremian,
Mawsonia
was widespread across western Gondwana, but its Aptian–Cenomanian records in South America are restricted to northeastern Brazil (including the Borborema tectonic province and adjacent areas to its north). In contrast,
Mawsonia
remained widespread in the Aptian–Cenomanian of Africa. Recently published data suggest that northeastern Brazil was still contiguous with Africa in the Aptian/Albian, although it was probably separated from the rest of South America by an epicontinental seaway that apparently followed an unconventional course across the Brazilian interior rather than along the present-day coastline. Aptian–Cenomanian records of
Mawsonia
and other non-marine taxa (including tetrapods) in northeastern Brazil may therefore represent ‘African’ rather than ‘South American’ biotas.
An Ecology of Sperm: Sperm Diversification by Natural Selection
Authors: Reinhardt Klaus , Dobler Ralph , Abbott Jessica
Published: October 2015

Using basic ecological concepts, we introduce sperm ecology as a framework to study sperm cells. First, we describe environmental effects on sperm and conclude that evolutionary and ecological research should not neglect the overwhelming evidence presented here (both in external and internal fertilizers and in terrestrial and aquatic habitats) that sperm function is altered by many environments, including the male environment. Second, we determine that the evidence for sperm phenotypic plasticity is overwhelming. Third, we find that genotype-by-environment interaction effects on sperm function exist, but their general adaptive significance (e.g., local adaptation) awaits further research. It remains unresolved whether sperm diversification occurs by natural selection acting on sperm function or by selection on male and female microenvironments that enable optimal plastic performance of sperm (sperm niches). Environmental effects reduce fitness predictability under sperm competition, predict species distributions under global change, explain adaptive behavior, and highlight the role of natural selection in behavioral ecology and reproductive medicine.
Constructing a Proto-Lexicon: An Integrative View of Infant Language Development
Authors: Johnson Elizabeth K.
Published: October 2015

Infants begin learning the phonological structure of their native language remarkably early and use this information to extract word-sized chunks from the speech signal. While acquiring the language-specific segmentation strategies appropriate for their native language, infants are simultaneously beginning to form word–object pairings and learning which sound contrasts are meaningful in the native language. They are also working out how to assign words to word classes, paying attention to the use and placement of function words, and learning how speakers of the language string words together to form sensible grammatical utterances. Amazingly, infants tackle all of these tasks simultaneously, with success in each of these domains dependent on success in the others. This review focuses on infants' discovery of word forms in speech, their construction of a proto-lexicon, and the development of linguistic knowledge during their first year and a half of life. By discussing the development of lexical knowledge in relation to other aspects of linguistic development, I demonstrate the advantages of an integrative approach to understanding early language acquisition.
Ocean Data Assimilation in Support of Climate Applications: Status and Perspectives
Authors: Stammer D. , Balmaseda M. , Heimbach P. , Köhl A. , Weaver A.
Published: October 2015

Ocean data assimilation brings together observations with known dynamics encapsulated in a circulation model to describe the time-varying ocean circulation. Its applications are manifold, ranging from marine and ecosystem forecasting to climate prediction and studies of the carbon cycle. Here, we address only climate applications, which range from improving our understanding of ocean circulation to estimating initial or boundary conditions and model parameters for ocean and climate forecasts. Because of differences in underlying methodologies, data assimilation products must be used judiciously and selected according to the specific purpose, as not all related inferences would be equally reliable. Further advances are expected from improved models and methods for estimating and representing error information in data assimilation systems. Ultimately, data assimilation into coupled climate system components is needed to support ocean and climate services. However, maintaining the infrastructure and expertise for sustained data assimilation remains challenging.
New Pharmacological Strategies to Increase cGMP
Authors: Buglioni Alessia , Burnett John C.
Published: October 2015

The intracellular nucleotide cyclic guanosine monophosphate (cGMP) is found in many human organ tissues. Its concentration increases in response to the activation of receptor enzymes called guanylyl cyclases (GCs). Different ligands bind GCs, generating the second messenger cGMP, which in turn leads to a variety of biological actions. A deficit or dysfunction of this pathway at the cardiac, vascular, and renal levels manifests in cardiovascular diseases such as heart failure, arterial hypertension, and pulmonary arterial hypertension. An impairment of the cGMP pathway also may be involved in the pathogenesis of obesity as well as dementia. Therefore, agents enhancing the generation of cGMP for the treatment of these conditions have been intensively studied. Some have already been approved, and others are currently under investigation. This review discusses the potential of novel drugs directly or indirectly targeting cGMP as well as the progress of research to date.
Liver Cancer: Connections with Obesity, Fatty Liver, and Cirrhosis
Authors: Marengo Andrea , Rosso Chiara , Bugianesi Elisabetta
Published: October 2015

The burden of hepatocellular carcinoma (HCC), the most common form of liver cancer, is steadily growing because obesity, type 2 diabetes, and nonalcoholic fatty liver disease (NAFLD) are replacing viral- and alcohol-related liver disease as major pathogenic promoters. The most worrisome aspects of these new risk factors are their large spread in the general population and their link with HCC arising in noncirrhotic livers. HCC may be the presenting feature of an asymptomatic nonalcoholic steatohepatitis (NASH), the progressive form of NAFLD. The HCC risk connected to metabolic factors has been underestimated so far, and a poorer surveillance has prevented an adequate treatment. Systemic and hepatic molecular mechanisms involved in obesity- and NAFLD-induced hepatocarcinogenesis as well as potential early markers of HCC are being extensively investigated. This review summarizes current evidence linking obesity, NAFLD and liver cancer, discusses its clinical impact and describes the main mechanisms underlying this complex relationship.
Prenatal Diagnosis Innovation: Genome Sequencing of Maternal Plasma
Authors: Wong Felix C.K. , Lo Y.M. Dennis
Published: October 2015

Noninvasive prenatal testing (NIPT) is accomplished by analysis of circulating cell-free fetal nucleic acids in maternal plasma. The advent of massively parallel sequencing (MPS) has enabled NIPT of chromosomal aneuploidies with unprecedented robustness, and these tests are now widely available for clinical use. Moreover, MPS-based NIPT of subchromosomal deletions/duplications and single-gene disorders has also been achieved, and the number of applications is growing. In addition to specific fetal genetic disorders, the whole fetal genome, transcriptome, and methylome have been revealed by deep sequencing of maternal plasma. The analysis of the fetal transcriptome and methylome may yield valuable information on fetal and maternal health. With continued improvement in sequencing technology and reduction in sequencing costs, the analysis of cell-free nucleic acids would play an increasingly important role in prenatal screening, diagnosis, monitoring, and risk stratification of fetal as well as maternal conditions.