bluuebunny/crossref_metadata_2025 huggingface dataset:
Neurochemical Alterations Associated with Borderline Personality Disorder
Authors: Atmaca Murad , Karakoc Tevfik , Mermi Osman , Gurkan Gurok M. , Yildirim Hanefi
Published: April 2016

In neuroimaging on borderline personality disorder, prior studies focused on the hippocampus and amygdala, as mentioned above. However, no study investigated whether there were neurochemical changes in the patients with borderline personality disorder. Therefore, in the present study, we aimed to investigate neurochemical change of patients diagnosed with borderline disorder and hypothesized that neurochemicals would change in the hippocampus region of these patients. Seventeen patients and the same number of healthy control subjects were analyzed by using a 1.5 Tesla GE Signa Imaging System. N-acetylaspartate (NAA), choline compounds (CHO), and creatine (CRE) values of hippocampal region were measured. The mean NAA/CRE ratio in the hippocampus region was significantly reduced in the patients with borderline personality disorder compared to that of healthy control subjects, In addition, NAA/CHO ratio of the patients with borderline personality disorder was also significantly reduced when compared to that of healthy subjects. There was no difference in the ratio of CHO/CRE. In summary, we present evidence for reduced NAA in the patients with borderline personality disorder.
Current and Future Trends in Electronic Cigarette Use
Authors: Mcgraw Dan
Published: April 2016

The controversy regarding the use of electronic cigarettes as a possible modality for smoking cessation has grown in recent years. Epidemiologic surveys indicate that usage rates in both adults and adolescents have increased substantially as the popularity of these devices continues to rise. At present, there is a small but growing body of evidence studying the possible role that these “e-cigarettes” may have as a nicotine replacement tool. Much of the existing data are from observational studies and surveys which track the epidemiologic and demographic trends of e-cigarette users. More recently-published articles have begun to utilize randomized, experimental designs to directly compare the efficacy of e-cigarettes to active and passive controls in outcome measures such as conventional cigarette quit rates and time to relapse. Barriers to widespread adoption of e-cigarette use as a smoking cessation modality include a lack of long-term safety and toxicology data, a lack of standardization of devices, and a debate regarding whether devices can be marketed for both social nicotine use, as well as nicotine replacement. A possible role of e-cigarettes that has not yet been explored is in the primary prevention of conventional cigarette use among young adults that are smoking-naïve.
Ultrafiltration Therapy for Heart Failure: Balancing Likely Benefits against Possible Risks
Authors: Kazory Amir
Published: April 2016

Heart failure remains a major public health concern because of its high prevalence, morbidity, mortality, and financial burden. The poor clinical outcomes associated with acute decompensated heart failure, suboptimal efficacy and safety profile of conventional treatment regimens, and unsatisfactory experiences with the newer classes of pharmacologic therapy underlie the interest in the use of extracorporeal isolated ultrafiltration in this setting. In this article, selected mechanistic aspects of ultrafiltration therapy are briefly reviewed followed by a critical overview of the largest trials in this field. I will discuss the clinical relevance of renal dysfunction and decongestion as two commonly used end points of safety and efficacy in the ultrafiltration trials, with emphasis on the emerging pertinent notions that could challenge our conventional thinking. Finally, a number of practical recommendations (e.g., customization of ultrafiltration rates) are provided for ultrafiltration therapy in the setting of acute decompensated heart failure. Because of a paucity of evidence, universally accepted consensus guidelines cannot yet be generated. As such, when considering ultrafiltration therapy for acute decompensated heart failure, the likely benefits should be carefully balanced against the potential risks for an individual patient. A conceivable implication of the ultrafiltration trials is that collaborative heart failure programs benefiting from nephrology expertise and resources could improve the outcomes and reduce the cost.
Relationship Between the Temperament Trait of Sensory Processing Sensitivity and Emotional Reactivity
Authors: Jagiellowicz Jadzia , Aron Arthur , Aron Elaine N.
Published: April 2016

Sensory processing sensitivity (SPS) is a temperament trait found in around 20% of humans, which has been found to enhance responsiveness to diverse stimuli. In this study, we investigated for the first time the extent to which SPS, and its interaction with quality of parenting, predicts
positive and negative experiences in response to emotional stimuli. Participants (N = 96) from the upper and lower quartiles on the standard SPS measure (the Highly Sensitive Person Scale) rated the valence and their arousal level when viewing emotionally evocative and neutral pictures
selected from the International Affective Picture System. High (vs. low) SPS individuals rated pictures eliciting emotion, and especially positive ones, as significantly more valenced, and tended to respond faster to the positive pictures; also, high, vs. low, SPS individuals who had reported
having high-quality parenting reported greater arousal in response to positive pictures. Overall, results suggest that high SPS individuals respond more strongly to emotional stimuli—especially positive—without being more aroused unless they had especially high-quality parenting.
Cognitive Diversity, Alertness, and Team Performance
Authors: Liao Zhongju , Long Siying
Published: April 2016

As a vital driver of team performance, cognitive diversity is of central interest to managers; however, the way in which cognitive diversity promotes superior team performance remains unclear. In this paper, we present a formal model that suggests the existence of the mediating effect
of alertness in this relationship. A quantitative method with multiple mediation models was applied to a sample of 1,020 members from 191 teams in China. Our results suggested that cognitive diversity had a significantly positive effect on team performance. Moreover, the mediating effects
of the 3 dimensions of alertness (information accumulation, information transformation, and information selection) were verified via a Sobel test. The implications of our findings, the limitations thereof, and possible directions for future research are discussed.
Effect of Interns' Learning Willingness on Mentors' Knowledge-sharing Behavior
Authors: Dong Mingyuan , Deng Dasong
Published: April 2016

We examined the effect of interns' learning willingness on the mentors' knowledge-sharing behavior, and examined organizational incentives and mentors' personality traits of openness and conscientiousness as moderators in this relationship. Participants were 180 mentor-intern dyads
at 10 teaching hospitals in China. We found that interns' willingness to learn had a significant positive effect on the knowledge-sharing behavior of mentors. The effect of organizational incentives on this relationship was dependent on the mentor's personality, such that when mentors were
low in either openness or conscientiousness, organizational incentives strengthened the relationship. Theoretical and managerial implications and directions for further research are discussed.
Can Implicit Attitudes Toward Other Countries be Changed?
Authors: Gao Xuchen , Lu Zheng , Liang Ningjian
Published: April 2016

We aimed to determine whether or not implicit attitudes toward other countries can be changed by priming with friend/enemy identification manipulations. Participants comprised 60 Chinese adult men whose implicit attitudes toward India and South Korea were measured with the Implicit
Association Test (IAT). They were then randomly assigned to 1 of 2 groups: pro-India, in which participants read a short article indicating that India was a friend and South Korea was an enemy, and pro-South Korea, in which the opposite primes were used. Participants then wrote a short paper
to support the assigned identity, and completed the IAT a second time. Repeated measures analyses of variance of IAT effects revealed a significant interaction between test time and groups, showing that implicit attitudes had been significantly changed by the 2 identification primes.
The Role of Parenting Behavior in Adolescents' Problematic Mobile Game Use
Authors: Jang YeiBeech , Ryu SeoungHo
Published: April 2016

With the rapid growth of smartphone use, problematic mobile game use among youth has become an increasingly salient social concern in South Korea. In this study, we empirically explored the relationship between parenting behavior and adolescents' problematic mobile game use. On the
basis of the developmental perspective, we focused on students in 3 different age groups (N = 1,018: elementary school, n = 401; middle school: n = 333; high school, n = 284) and observed noticeable differences according to age group. According to the hierarchical
multiple regression results, overexpectation was positively related to problematic mobile game use in all 3 age groups. However, affection was negatively related to problematic mobile game use only in the elementary school group, and monitoring was negatively related to problematic mobile
game use only in the high school group. Implications of the findings are discussed.
Conformity Behavior During a Fire Disaster
Authors: Duo Qi , Shen Huizhang , Zhao Jidi , Gong Xiaomin
Published: April 2016

A fire disaster can involve severe personal injury, and individuals may take various actions to respond to such threats—in particular, following others' behavior when trying to escape. In this experimental study, 114 participants watched a video about escaping from a fire, then
prepared an emotional-experience report and decided which of 2 or 4 options they would choose in a situation. Results revealed that individuals exposed to a fire situation experienced a significantly higher level of fear activation, inferior decision-making performance, and higher conformity
tendency than did those exposed to a nonemergency situation. Further, the number of choices offered for making an escape was negatively related to conformity behavior, and decision-making performance was found to be a dual mediator both between the level of fear activation and conformity behavior
and between the number of choices and conformity behavior.
The role of contact and perceived attitudes of surroundings in children’s acceptance of “different” peers
Authors: Maricic Jelena , Mihalj Marko
Published: April 2016

This study was conducted with Croatian fourth grade students (N=691) that
were divided into two groups. The characters presented in vignettes had some
type of stigmatizing feature (e.g., Roma nationality, wheelchair usage, or
being overweight) in the experimental group, while these features were left
out in the comparison group. The first goal was to examine the impact of each
stigmatizing feature on the non-acceptance of the described characters. The
second goal was to analyze the relationship between the non-acceptance of the
stigmatized character and children?s established contact with people with
similar features, as well as the relationship between the afore-mentioned and
the perceived attitudes of parents and friends. Roma ethnicity had a
significant influence on non-acceptance of the character, while contact was
related to an increase in the level of non-acceptance of the Roma character.
Negative perceived opinions of friends regarding individuals with
stigmatizing features (regardless of the type) were related to a lower level
of acceptance of that character.
Determinants and Consequences of Nonprofit Debt Ratings
Authors: Gaver Jennifer J. , Harris Erica E. , Im S. Mary
Published: April 2016

SYNOPSIS

We use a comprehensive sample of over 400 nonprofit organizations that received a bond rating from Moody's or S&P between 1997 and 2010 to investigate the types of nonprofits that purchase a rating and the association between ratings and donations. Compared to organizations without ratings, our results indicate that bond ratings are purchased by larger organizations and those with more debt. We also find evidence that donors' use of information provided by bond ratings is limited to hospitals and universities. This result likely occurs because donors to hospitals and universities are more aware of debt ratings than donors to other nonprofit organizations. An implication is that nonprofits in other industries should consider disseminating bond rating information directly to potential donors as part of their fundraising efforts.
Narrow gap laser welding for potential nuclear pressure vessel manufacture
Authors: Feng Jiecai , Guo Wei , Francis John , Irvine Neil , Li Lin
Published: April 2016

High power density electron beam and laser beam welding show their unique advantages in the welding of thick-section steels for potential nuclear pressure vessel manufacture. Compared with traditional submerged arc welding or newly developed narrow-gap submerged arc welding, electron beam welding and laser beam welding techniques offer high welding speeds, low heat inputs, lower levels of residual stresses and distortion, while consuming less filler material and power. As a part of the new nuclear manufacturing EPSRC Program, this study aimed to develop narrow gap laser welding procedures and parameters for joining 30–130 mm thick ferritic steels for potential application to pressure vessel manufacture in civil nuclear power plants. The results showed that high quality welded joints in 30 mm thick steels had been achieved with a combination of an autogenous root pass and multipass narrow gap (4–5 mm parallel grooves) welding with a defocused laser beam welding and filler wire addition, at laser powers of 7.5–8 kW, a welding velocity of 0.4 m/min, a diameter of the laser spot of 6 mm, and wire feed rates of 4–6 m/min. The results also showed that cracking, lack of sidewall fusion, and porosity were the main defects in multiple pass narrow gap laser welds in thick-section ferritic steels if the welding parameters were not optimized. The microhardness of the multipass weld was lower than that of the autogenous weld as tempered martensite was achieved in multipass welding.
Hardware-in-the-loop control of additive manufacturing processes using temperature feedback
Authors: Devesse Wim , De Baere Dieter , Hinderdael Michaël , Guillaume Patrick
Published: April 2016

Laser-based additive manufacturing is a technology for the production of freeform metallic parts. In order to produce parts with high quality, it is important for the manufacturing processes to be controllable with a high degree of precision. Current additive manufacturing systems attempt to reach this goal by carefully tuning the operational parameters, often in combination with a feedback control system. These systems are based on low order, empirical models of the process, which may limit the performance that can be achieved. This paper introduces a control system based on a high order physical heat conduction model of the melt pool dynamics. The control system serves as a framework which can be applied to many laser material processes in which high precision is required such as laser cladding and selective laser melting. The controller is able to regulate the melt pool size by modulating the laser power using a number of surface temperature measurements as the feedback signal. A hardware-in-the-loop (HIL) system was built to enable safe and cost-effective testing of the controller hardware in different simulation environments. The HIL setup includes a real-time image processing module for extracting the required temperature information from hyperspectral data generated by detailed numerical simulations of the melt pool dynamics. Hyperspectral measurements are performed on a laser cladding system to validate the simulation results.
Influence of moisture content in fiber reinforced polyetherimide on laser weld seam quality
Authors: Wippo Verena , Mangold Johannes , Jaeschke Peter , Suttmann Oliver , Overmeyer Ludger
Published: April 2016

Fiber reinforced materials are present in a wide field of industrial applications, due to their good strength-weight-ratio. This is especially true for thermoplastic composites, which have the advantage of high impact tolerances, quick forming processing capability, and weldability. These materials can be joined, for example, by laser transmission welding. For several thermoplastics, the weld seam quality is affected by the moisture content of the joining members. During laser transmission welding, the welding members are heated up and water in the composite evaporates, causing cavities in the weld seam. For reliable joining connections between thermoplastic parts with high moisture content, it is necessary to determine the effect of moisture on the weld seam quality. Therefore, the influence of the moisture content on the weld seam quality was investigated. The joining members consisted of endless glass fiber reinforced polyetherimide and endless carbon fiber reinforced polyetherimide, which were conditioned in three different ways. Afterward, lap shear and cross section samples were prepared and analyzed.
Effect of optical parameters on fiber laser welding of ultrahigh strength steels and weld mechanical properties at subzero temperatures
Authors: Salminen Antti , Farrokhi Farhang , Unt Anna , Poutiainen Ilkka
Published: April 2016

The recently developed direct-quenched ultrahigh strength steels have a combination of high tensile strength and toughness properties at subzero temperatures down to −80 °C. The low carbon content of the material is beneficial for weldability. Modern high power lasers provide an excellent opportunity to modify the focal point diameter by changing the feeding fiber diameter, collimation and focal length, and thus modify the beam intensity and heat input in actual welding process. In this study, butt joints of Optim 960 QC direct-quenched ultrahigh strength steel with a thickness of 8 mm were welded with 10 kW fiber laser with various different optical setups in order to evaluate the characteristics of the joints within the range of low to high heat inputs possible for this welding process. The mechanical properties of the joints were studied by subjecting the specimens to a number of destructive tests of mechanical properties. The weld metal hardness and tensile strength was tested. It was found that high quality butt joints with superior tensile strength could be obtained. However, having a high level of all these properties in the joint narrows, the process parameters' window and the heat input needs to be strictly controlled.
Effect of the welding process and filler material on the fatigue behavior of 960 MPa structural steel at a butt joint configuration
Authors: Siltanen Jukka , Skriko Tuomas , Björk Timo
Published: April 2016

Ultrahigh-strength steels are being used more and more frequently in the engineering industry. Normally, the welding of these steels is more demanding. The welding requires a controlled heating and cooling rate. In this study, the S-N curves were determined for the laser, the laser-gas metal arc hybrid (Laser-GMA hybrid welding, LHW) and the gas metal arc welding (GMAW) welded joints according to the recommendations of the International Institute of Welding (IIW) by using a constant amplitude loading and a stress ratio of R = 0.1. The frequency of loading varied between 4 and 10 Hz. The tested material was direct quenched steel with a yield strength of 960MPa and a thickness of 6 mm. The total amount of tested specimens was 51. The fatigue test results have proven to be close to the IIW recommendations and the differences between various welding processes were minor. Instead of welding process or filler material, the main factor influencing the fatigue behavior was the geometry of the weld. Consequently, the proper welding parameters should be applied in every welding process in order to achieve a smooth joint geometry and, thus, a high fatigue resistance.
Visualization of flow separation inside cut kerf during laser cutting of thick sections
Authors: Zhang Chi , Wen Peng , Yao Zhaohui , Yuan Yueming , Fan Xuejun
Published: April 2016

The behavior of oxygen gas not only determines the oxidation heat input but also affects the removal of molten metal during laser-oxygen cutting. Flow separation inside the cut kerf is the major problem for the deterioration of cut ability and cut quality, especially for cutting thick steel sections, because it significantly weakens the shear stress on molten slag and changes the pressure gradient along the cut front. There have been some researches on flow separation using numerical simulation and model kerf. However, many experimental details and results are unclear, and the numerical simulation is questionable due to lack of experimental verification. In this paper, a model kerf is set up based on the previous results of observation and cutting trials. High resolution and high speed Schlieren visualization is used to observe the formation of flow separation in the model kerf. Stand-off distance, inlet pressure, cut front slope, nozzle displacement, kerf width, and nozzle tilting angle are used as variables for Schlieren visualization of flow separation for both a conical subsonic and a minimum length nozzle supersonic nozzle. The effect of the above parameters on the position and the pattern of flow separation is discussed based on the gas dynamic theory. It is found that nozzle displacement, kerf width, and nozzle tilting angle are the key factors for flow separation. Possible strategies for controlling flow separation are also proposed for both subsonic and supersonic nozzles.
Modifications of surface properties of beta Ti by laser gas diffusion nitriding
Authors: Ng Chi-Ho , Chan Chi-Wai , Man Hau-Chung , Waugh David , Lawrence Jonathan
Published: April 2016

β-type Ti-alloy is a promising biomedical implant material as it has a low Young's modulus and is also known to have inferior surface hardness. Various surface treatments can be applied to enhance the surface hardness. Physical vapor deposition and chemical vapor deposition are two examples of this but these techniques have limitations such as poor interfacial adhesion and high distortion. Laser surface treatment is a relatively new surface modification method to enhance the surface hardness but its application is still not accepted by the industry. The major problem of this process involves surface melting which results in higher surface roughness after the laser surface treatment. This paper will report the results achieved by a 100 W continuous wave (CW) fiber laser for laser surface treatment without the surface being melted. Laser processing parameters were carefully selected so that the surface could be treated without surface melting and thus the surface finish of the component could be maintained. The surface and microstructural characteristics of the treated samples were examined using x-ray diffractometry, optical microscopy, three-dimensional surface profile and contact angle measurements, and nanoindentation test.
Analysis of the physical processes occurring during deep penetration laser welding under reduced pressure
Authors: Fabbro Remy , Hirano Koji , Pang Shengyong
Published: April 2016

Recent published experimental results obtained on deep penetration laser welding realized under reduced ambient pressure have shown very interesting results: resulting weld seams have geometrical characteristics that are similar to those obtained with electron beams. They show an increased penetration depth that can reach a factor two compared to atmospheric experiments, a larger aspect ratio with narrow and parallel sides of the weld seam. Also some humps around the rim of the keyhole appear. Of course, these modifications depend on the ambient pressure, but one also observes that these interesting improvements become independent of the ambient pressure below some critical pressure and also disappear at high welding speeds. Moreover, it is also observed that this critical pressure, below which these improvements do not vary, increases with the welding speed. In these previous publications, all these different characteristic results have not been explained. It is therefore the purpose of this paper to explain these different results. This has been obtained by using 3D numerical simulations of deep penetration laser welding and by studying the corresponding variation of physical parameters inside the keyhole (temperature, recoil pressure, and hydrodynamics of the vapor plume). An explanation for the evolution of these resulting weld seam geometries, as a function of the main operating parameters is proposed: ambient pressure, welding speed, and laser beam parameters (power and beam spot diameter). It is then possible to estimate this characteristic critical pressure, which is compared favorably with the corresponding previous experimental results. As a consequence, this analysis allows to define the optimum conditions for the improvement of the weld seam characteristics realized under reduced ambient pressure for an industrial environment.
Thermomechanical numerical analysis of hot cracking during laser welding of 6XXX aluminum alloys
Authors: Wei Haoyan , Chen J. S. , Wang Hui-Ping , Carlson Blair E.
Published: April 2016

The finite element method is applied to study the mechanisms inducing hot cracking during laser welding of 6xxx aluminum alloys. The welding process of a single-sheet plate is modeled by adopting a three dimensional fully coupled thermomechanical finite element formulation, where the energy distribution due to a fiber laser heat source and the motion trajectory of the moving laser beam are specified. The temperature dependent material behavior of aluminum alloys is described by a thermo-elastic-plastic constitutive law which assumes isotropic hardening, and the plastic strain history is reinitialized during the melting and solidification process. With this numerical model, the critical mechanical and thermal responses in the welded metal sheet are used to investigate potential hot cracking mechanisms. It is found that the heat flux vector field obtained through simulation is consistent with the grain orientation in the weld bead observed experimentally. The large tensile stress in the semisolid mushy zone near the fusion line is used as an indicator for identification of hot crack initiation, which is shown to be in the direction normal to the welding line. As the crack grows from the fusion line into the weld centerline, due to the high transverse tensile thermal stress developed inside the weld central region, the crack propagation then shifts to the weld line direction. Furthermore, the effects of several manufacturing process parameters on hot cracking susceptibility are investigated. The results reveal that a smaller weld line-to-edge distance would result in a higher tensile stress state near the fusion line in the mushy zone, and thus increase the possibility of crack formation which is consistent with the experimental observations. Preliminary results also suggest that higher laser power or slower welding speed could increase the hot cracking susceptibility.
Study on laser-MAG hybrid weaving welding characteristics for high-strength steel
Authors: Cai Chuang , Li Liqun , Chen Xinya , Feng Jiecai
Published: April 2016

To improve the inhomogeneous morphology and porosity defects of the laser-MAG hybrid welds, laser-MAG synchronized weaving welding and scanning laser-MAG hybrid welding were developed for the bead on plate welding of high-strength steel. Based on the mechanical motion of robot, the laser beam and arc torch synchronized weaving were realized during the laser-MAG synchronized weaving welding process. With respect to scanning laser-MAG hybrid welding, only laser beam weaving was performed using the scan head. The influences of weaving frequency on the weld formation and porosity defects were investigated. The mechanical properties, including the ultimate tensile strength and impact toughness, were comparatively discussed. The results indicate that the desired homogeneity and continuity of weld morphology could be obtained under the condition that the weaving frequency was no less than 6 Hz. Scanning laser-MAG hybrid welding is an alternative technique for weaving welding compared to laser-MAG synchronized weaving welding. The weld penetration decreased with the increasing weaving frequency. The maximum reduction of weld penetration was about 43.7% compared to that of laser-MAG hybrid welding. The optimal weaving frequency for the porosity defects suppression was 20 Hz. The welds of scanning laser-MAG hybrid welding with the weaving frequency of 20 Hz possessed better impact toughness, increased by about 31.4% than that of laser-MAG hybrid welding. The weld porosity defects were suppressed due to the stirring effect of laser beam to the molten pool. The formation of staggered columnar crystal in the weld prevented the crack propagation successfully during the impact testing process.
Laser localized coating of corrosion resistant metal over a steel weld bead
Authors: Gu Hongping , Van Gelder Aldo
Published: April 2016

Coated steel sheet is one of the most important raw materials for the automotive industry. The commonly used Al or Zn based coatings on steel sheet provide a physical barrier and/or galvanic protection, and thus prevents a corrosive attack of the steel substrate. In order to make complex component or assembly, several steel sheets of various sizes, shapes, or thicknesses are welded together before or after being formed. Unfortunately, the process of welding together the precoated steel sheet pieces results in the formation of a weld joint that is devoid of anticorrosion protection. Re-formation of the protective coating over the weld joint could greatly improve the final product's quality in terms of resistance to corrosion. In this investigation, recoating of aluminum-silicon over laser weld joints has been explored by laser beam heating and powder injection. Precise coating over the weld joint was achieved. The produced coating on the welding bead is smooth when proper processing parameters are employed.
Full penetration laser beam welding of thick duplex steel plates with electromagnetic weld pool support
Authors: Avilov Vjaceslav , Fritzsche André , Bachmann Marcel , Gumenyuk Andrey , Rethmeier Michael
Published: April 2016

Full penetration high power bead-on-plate laser beam welding tests of up to 20 mm thick 2205 duplex steel plates were performed in PA position. A contactless inductive electromagnetic (EM) weld pool support system was used to prevent gravity drop-out of the melt. Welding experiments with 15 mm thick plates were carried out using IPG fiber laser YLR 20000 and Yb:YAG thin disk laser TruDisk 16002. The laser power needed to achieve a full penetration was found to be 10.9 and 8.56 kW for welding velocity of 1.0 and 0.5 m min−1, respectively. Reference welds without weld pool support demonstrate excessive root sag. The optimal value of the alternating current (AC) power needed to completely compensate the sagging on the root side was found to be ≈1.6 kW for both values of the welding velocity. The same EM weld pool support system was used in welding tests with 20 mm thick plates. The laser beam power (TRUMPF Yb:YAG thin disk laser TruDisk 16002) needed to reach a full penetration for 0.5 m min−1 was found to be 13.9 kW. Full penetration welding without EM weld pool support is not possible—the surface tension cannot stop the gravity drop-out of the melt. The AC power needed to completely compensate the gravity was found to be 2 kW.
Photonic nanomanufacturing of high performance energy devices on flexible substrates
Authors: Hu A. , Li R. , Bridges D. , Zhou W. , Bai S. , Ma D. , Peng P.
Published: April 2016

The authors have investigated various photonic processing for various energy devices on flexible substrates with nanoinks. For printable electronics, different conducting nanoinks are developed, including silver nanowires, silver nanoplates, Cu-Ag core-shell nanoparticles, graphene oxide, and graphene. The authors showed that these inks are enabling for direct writing of antenna on paper for radio frequency (RF) energy harvesting, potentially for wireless charging application. For curing printed nanoinks and nanopastes, the authors compared four kinds of methods: chemical activated self-sintering, thermal sintering, photonic sintering with flash light, and athermal sintering with ultrafast fiber laser irradiation. The authors also developed an innovative and facile approach to fabricate supercapacitors on flexible substrates with femtosecond laser writing and photonic reduction. Au-reduced graphene oxide nanocomposite is used for electrical electrodes and collectors. Unlike previous studies, collectors are fabricated through conventional photolithography gold electrodes is directly written by femtosecond laser reduction of Au ions. The authors found that gold nanoparticles can be well sintered on the surface of reduced graphene. The reduced graphene also work as glues to bridge the electrical interconnection. The measured conductivity of Au/reduced graphene reaches 10% of that of bulk gold. By optimizing an interdigital structure, the areal capacitor is achieved as 1.5 mF/cm2.
Laser sealing of dissimilar polymers for manufacturing packaging products
Authors: Shukla Pratik , Lawrence Jonathan , Waugh David G.
Published: April 2016

Laser sealing of thin/dissimilar polymers has the potential to become a superior technique that could be applied to a range of general packaging products. Upon successfully applying laser sealing to such products could result to faster throughputs, shorter lead-times, lower energy consumption, and in turn, a competitive advantage for packaging product manufacturers. The work herein is focused on the physical laser-material interaction resulting from laser sealing a 42 μm high density linear polyethylene (HDLPE) film to a 1 mm polypropylene (PP) substrate. The paper also details a comparison of laser sealing with the conventional pressure/heat sealing process. The results showed that a 10.6 μm wavelength laser, the required parameters to produce an acceptable seal were: 60 W of laser power, 1.67 mm spot diameter, and a traverse speed of 300 mm/min using a double pass. Microstructural study showed sufficient bonding of the laser sealed region with an amorphous zone. Defects were also present in various areas when comparing the results of laser sealing to the conventional sealing process. Nonetheless, the peel strength tests showed laser sealing required up to 30% higher force than the conventionally sealed HDLPE film to PP substrate. A steady-state finite element model of the laser sealing process showed distribution of heat at the film/seal activation temperature. This confirmed the sealing temperature at the laser-polymer interaction zone to gain further understanding of the new process as a whole.
Patellofemoral Osteoarthritis: Are We Missing an Important Source of Symptoms After Anterior Cruciate Ligament Reconstruction?
Authors: Culvenor Adam G. , Crossley Kay M.
Published: April 2016

Anterior cruciate ligament (ACL) rupture is a well-established risk factor for knee osteoarthritis (OA). Fifty to ninety percent of individuals will develop radiographic tibiofemoral OA within a decade after ACL injury and anterior cruciate ligament reconstruction (ACLR). Although less well recognized, radiographic patellofemoral OA is present in approximately 50% of individuals at more than 10 years after ACLR. This early-onset OA and its associated pain and functional limitations pose a particular challenge to younger adults with OA compared to an older OA population. Targeted interventions need to be developed to reduce the burden of early-onset OA following ACLR. Emerging evidence suggests that such interventions should target both the patellofemoral and tibiofemoral joints.

J Orthop Sports Phys Ther 2016;46(4):232–234. doi:10.2519/jospt.2016.0603
Increased incidence of invasive meningococcal disease of serogroup C / clonal complex 11, Tuscany, Italy, 2015 to 2016
Authors: Stefanelli Paola , Miglietta Alessandro , Pezzotti Patrizio , Fazio Cecilia , Neri Arianna , Vacca Paola , Voller Fabio , D’Ancona Fortunato P. , Guerra Raniero , Iannazzo Stefania , Pompa Maria Grazia , Rezza Giovanni
Published: April 2016

We report an increase of serogroup C Neisseria meningitidis invasive meningococcal disease in Tuscany. From January 2015 to end February 2016, 43 cases were reported, among which 10 were fatal, compared to two cases caused by serogroup C recorded in 2014 and three in 2013. No secondary cases occurred. Thirty–five strains belonged to C:P1.5–1,10–8:F3–6:ST-11(cc11). Control measures have been adopted and immunisation campaigns implemented. Studies on risk factors and carriage are ongoing.
Masseteric–facial nerve neurorrhaphy: results of a case series
Authors: Biglioli Federico , Colombo Valeria , Rabbiosi Dimitri , Tarabbia Filippo , Giovanditto Federica , Lozza Alessandro , Cupello Silvia , Mortini Pietro
Published: April 2016

OBJECTIVE

Facial palsy is a well-known functional and esthetic problem that bothers most patients and affects their social relationships. When the time between the onset of paralysis and patient presentation is less than 18 months and the proximal stump of the injured facial nerve is not available, another nerve must be anastomosed to the facial nerve to reactivate its function. The masseteric nerve has recently gained popularity over the classic hypoglossus nerve as a new motor source because of its lower associated morbidity rate and the relative ease with which the patient can activate it. The aim of this work was to evaluate the effectiveness of masseteric–facial nerve neurorrhaphy for early facial reanimation.

METHODS

Thirty-four consecutive patients (21 females, 13 males) with early unilateral facial paralysis underwent masseteric–facial nerve neurorrhaphy in which an interpositional nerve graft of the great auricular or sural nerve was placed. The time between the onset of paralysis and surgery ranged from 2 to 18 months (mean 13.3 months). Electromyography revealed mimetic muscle fibrillations in all the patients. Before surgery, all patients had House-Brackmann Grade VI facial nerve dysfunction. Twelve months after the onset of postoperative facial nerve reactivation, each patient underwent a clinical examination using the modified House-Brackmann grading scale as a guide.

RESULTS

Overall, 91.2% of the patients experienced facial nerve function reactivation. Facial recovery began within 2–12 months (mean 6.3 months) with the restoration of facial symmetry at rest. According to the modified House-Brackmann grading scale, 5.9% of the patients had Grade I function, 61.8% Grade II, 20.6% Grade III, 2.9% Grade V, and 8.8% Grade VI. The morbidity rate was low; none of the patients could feel the loss of masseteric nerve function. There were only a few complications, including 1 case of postoperative bleeding (2.9%) and 2 local infections (5.9%), and a few patients complained about partial loss of sensitivity of the earlobe or a small area of the ankle and foot, depending on whether great auricular or sural nerves were harvested.

CONCLUSIONS

The surgical technique described here seems to be efficient for the early treatment of facial paralysis and results in very little morbidity.
Patterns of recurrence and survival in sporadic, neurofibromatosis Type 1–associated, and radiation-associated malignant peripheral nerve sheath tumors
Authors: Watson Kelsey L. , Al Sannaa Ghadah A. , Kivlin Christine M. , Ingram Davis R. , Landers Sharon M. , Roland Christina L. , Cormier Janice N. , Hunt Kelly K. , Feig Barry W. , Ashleigh Guadagnolo B. , Bishop Andrew J. , Wang Wei-Lien , Slopis John M. , McCutcheon Ian E. , Lazar Alexandar J. , Torres Keila E.
Published: April 2016

OBJECTIVE

Malignant peripheral nerve sheath tumors (MPNSTs) are an aggressive group of soft tissue sarcomas that can arise sporadically, in the context of neurofibromatosis Type 1 (NF1) or at a site of prior irradiation. Large series profiling the features and outcomes of sporadic, NF1-associated, and radiation-associated MPNSTs are limited. The goal of this study was to elucidate differences between MPNST etiologies in a large single-institution retrospective study.

METHODS

Patients (n = 317) were identified through the tumor registry of The University of Texas MD Anderson Cancer Center. Clinicopathological features were retrospectively collected. Features were compared among MPNST subtypes for patients who had sufficient clinical history (n = 289), and clinicopathological features were used to identify adverse predictors of recurrence and survival outcomes.

RESULTS

Five-year local recurrence-free survival (LRFS), distant recurrence-free survival (DRFS), and disease-specific survival (DSS) estimates were 56.6%, 49.6%, and 53.6%, respectively, for the high-grade MPNST cohort. Five-year DSS was lower in NF1-associated and radiation-associated MPNST than in sporadic MPNST (52%, 47%, and 67%, respectively, p = 0.140). Patients with radiation-associated MPNST had worse 5-year LRFS than those with the sporadic and NF1-associated subtypes (RT-associated vs sporadic, p = 0.010; RT-associated vs NF1-associated, p = 0.232). Truncally located tumors, positive surgical margins, local recurrence, and metastasis were predictors of adverse DSS in multivariate analysis.

CONCLUSIONS

Radiation-associated MPNSTs are associated with poorer local recurrence-free and disease-specific survival than sporadic and NF1-associated tumors. NF1-associated MPNSTs may have worse survival outcomes owing to large tumor size, compromising truncal location, and lower rate of negative resection margins compared with sporadic tumors.
Differential spatial regulation of BMP molecules is associated with single-suture craniosynostosis
Authors: Whitton Alaina , Hyzy Sharon L. , Britt Chelsea , Williams Joseph K. , Boyan Barbara D. , Olivares-Navarrete Rene
Published: April 2016

OBJECTIVE

The aim of this study was to examine messenger RNA (mRNA) levels of bone morphogenetic protein (BMP) ligands, receptors, and soluble inhibitors in cells isolated from single-suture synostoses from fused coronal, metopic, sagittal, and lambdoid sutures.

METHODS

Cells were isolated from bone collected from patients undergoing craniotomies at Children's Healthcare of Atlanta. Real-time polymerase chain reaction was used to examine mRNA levels in cells isolated from fused sutures or patent sutures in comparison with levels in normal bone from the same patient.

RESULTS

Cells isolated from fused sutures in cases of sagittal and coronal synostosis highly expressed BMP2, while cells isolated from fused metopic or lambdoid synostosis expressed high BMP4. Noggin, a BMP inhibitor, was lower in fused sutures and had high expression in patent sutures.

CONCLUSIONS

These results suggest that BMPs and inhibitors play a significant role in the regulation of suture fusion as well in the maintenance of patency in the normal suture.
Retirement-from-sport considerations following pediatric sports-related concussion: case illustrations and institutional approach
Authors: Ellis Michael J. , McDonald Patrick J. , Cordingley Dean , Mansouri Behzad , Essig Marco , Ritchie Lesley
Published: April 2016

The decision to advise an athlete to retire from sports following sports-related concussion (SRC) remains a persistent challenge for physicians. In the absence of strong empirical evidence to support recommendations, clinical decision making must be individualized and should involve a multidisciplinary team of experts in concussion and traumatic brain injury. Although previous authors have advocated for a more conservative approach to these issues in child and adolescent athletes, there are few reports outlining considerations for this process among this unique population. Here, the authors use multiple case illustrations to discuss 3 subgroups of clinical considerations for sports retirement among pediatric SRC patients including the following: those with structural brain abnormalities identified on neuroimaging, those presenting with focal neurological deficits and abnormalities on physical examination, and those in whom the cumulative or prolonged effects of concussion are suspected or demonstrated. The authors' evolving multidisciplinary institutional approach to return-to-play and retirement decision making in pediatric SRC is also presented.
Severe holocord syrinx in a child with megalencephaly-capillary malformation syndrome
Authors: Segal Devorah , Heary Robert F. , Sabharwal Sanjeev , Barry Maureen T. , Ming Xue
Published: April 2016

The authors present the case of a child with megalencephaly-capillary malformation syndrome who developed a rapidly progressive holocord syringomyelia that was treated surgically. A 3-year-old boy with megalencephaly-capillary malformation-polymicrogyria (MCAP) syndrome presented with several months of right leg weakness, worsening scoliosis, and increased seizures. An MRI study of the brain demonstrated a Chiari I malformation and massively dilated syringomyelia extending from C-2 to the conus medullaris. The patient underwent an urgent suboccipital craniectomy with C1–3 laminectomies to relieve the CSF outflow obstruction with significant clinical improvement. Surgery was complicated by bleeding from intracranial vascular malformations. This report describes a very rapidly developing, massive holocord syringomyelia related to CSF obstruction due to an unusual congenital brain malformation and associated vascular overgrowth at the site. Serial, premorbid MRI studies demonstrated the very rapid progression from no Chiari malformation, to progressively greater cerebellar tonsillar herniation, to holocord syrinx. This complication has never been reported in MCAP syndrome and should be considered in any affected MCAP patient with a progressive neurological decline, even if previous spine imaging findings were normal. Surgical complications due to hemorrhage also need to be considered in this vascular brain malformation.
The use of spine stereotactic radiosurgery for oligometastatic disease
Authors: Ho Jennifer C. , Tang Chad , Deegan Brian J. , Allen Pamela K. , Jonasch Eric , Amini Behrang , Wang Xin A. , Li Jing , Tatsui Claudio E. , Rhines Laurence D. , Brown Paul D. , Ghia Amol J.
Published: April 2016

OBJECTIVE

The authors investigated the outcomes following spine stereotactic radiosurgery (SSRS) for patients with oligometastatic disease of the spine.

METHODS

The study was a secondary analysis of 38 of 209 patients enrolled in 2 separate institutional Phase I/II prospective protocols and treated with SSRS between 2002 and 2011. Of these 38 patients, 33 (87%) were treated for a solitary spine metastasis, with no other history of metastatic disease. SSRS was prescribed to 24 Gy in 1 fraction (8%), 18 Gy in 1 fraction (18%), 16 Gy in 1 fraction (11%), 27 Gy in 3 fractions (53%), 30 Gy in 5 fractions (8%), or 20 Gy in 5 fractions (3%). Seventeen patients (45%) received prior conventional external beam radiation therapy.

RESULTS

The median overall survival (OS) was 75.7 months, and the 2- and 5-year OS rates were 84% and 60%, respectively. In multivariate analysis, patients who had prior spine surgery and a better Karnofsky Performance Scale score had an improved OS (HR 0.16, 95% CI 0.05–0.52, p < 0.01, and HR 0.33, 95% CI 0.13%–0.84%, p = 0.02, respectively), and those who had undergone prior radiation therapy had a worse OS (HR 3.6, 95% CI 1.2%–10%, p = 0.02). The 1-, 2-, and 5-year local progression-free survival rates were 85%, 82%, and 78%, respectively. The median time to systemic therapy modification was 41 months. Two patients (5%) experienced late Grade 3–4 toxicity.

CONCLUSIONS

Patients with oligometastatic disease of the spine treated with SSRS can experience long-term survival and a long time before needing a modification in systemic therapy. In addition, SSRS leads to excellent local control and minimal late toxicity.