bluuebunny/crossref_metadata_2025 huggingface dataset:
Imaging Analysis of Onodi Cells on Cone-Beam Computed Tomography
Authors: Ali Ibrahim K. , Sansare Kaustubh , Karjodkar Freny , Saalim Mohd
Published: December 2019

Introduction Onodi cells are the most posterior ethmoid air cells, and extend superolaterally to the sphenoid sinus. The identification of Onodi cells is essential to because they can have some significant anatomic variations and relationships to vital adjacent structures, like the optic canal, the sphenoid sinus, and the internal carotid artery.

Objective The present study aimed to assess the prevalence of Onodi cells and their position with respect to sphenoid sinus. To the authors' best knowledge, this is the first study that uses cone-beam computed tomography (CBCT) to assess the prevalence and position of Onodi cells.

Methods We collected CBCT scan records from November 1st, 2016, to July 31st, 2017; the patients who fulfilled the eligibility criteria were included in the present study. The CBCT scans were reviewed by two independent observers. The descriptive statistics was performed using the Statistical Package for the Social Sciences (SPSS, SPSS, Inc., Chicago IL, US) software, version 17.0. A cross-tabulation of gender with the presence and position of Onodi cells was evaluated using the Chi-squared (χ2) test. The inter- and intraobserver agreements were evaluated using Kappa (κ) statistics.

Results Onodi cells were identified in 86 (42.8%) out of 201 patients. A subgroup analysis revealed that Onodi cells were present in 45 (43.3%) female and 41 (42.3%) male patients. The position of the Onodi cells was superior with respect to the sphenoid sinus in 43 (50%) of the patients, superolateral in 36 (41.9%), and lateral to the sphenoid sinus in 7 (8.1%) of the patients.

Conclusion The present study indicated a high prevalence of Onodi cells, with approximately equal distribution among males and females, and mostly superior in position in relation to the sphenoid sinus.
The Anatomy and Anatomical Variations of the Round Window Prechamber and Their Implications on Cochlear Implantation: An Anatomical, Imaging, and Surgical Study
Authors: Mehanna Ahmed Mohamed , Abdelnaby Moustafa Mohamed , Eid Mohamed
Published: December 2019

Introduction Over the last decades, there has been a tremendous increase in the number of cochlear implant recipients and, consequently, there is a recent increase of interest in the proper understanding of the anatomy of the round window (RW), which is the most important anatomical land mark during cochlear implant surgery.

Objectives The present study was undertaken to assess the detailed surgical and radiological anatomy of the RW prechamber; its shape, directions, measurements, common anatomic variations, and its relationships with different surrounding structures as related to cochlear implantation.

Methods A total of 20 cadaveric specimens of human temporal bone were microscopically dissected for the anatomical assessment of the measurements of the RW and its relation to surrounding structures in the tympanum. A total of 20 patients were subjected to cochlear implantation, and a radiological and surgical assessment of the anatomy of their RW prechambers was performed.

Results The distances between the RW and the facial canal (FC), the jugular fossa (JF), the carotid canal (CC), and the oval window (OW) were measured. Among the cases subjected to cochlear implantation, the infracochlear tunnel was studied radiologically; the lengths of the anterior and posterior pillars were assessed, and the relation with the direction at which the RW faces was statistically analyzed.

Conclusions Proper understanding of the topographic anatomy of the RW, including its direction of opening and the distances from different adjacent structures in the tympanum, is essential for a successful cochlear implantation surgery, since it can help decision-making before the surgery and is useful to avoid many complications, such as misplaced electrode and iatrogenic injury to the surrounding structures.
Importance of Facial Plastic Surgery Education in Residency: A Resident Survey
Authors: Curti Steven A. , Jordan J. Randall
Published: December 2019

Introduction Facial plastic and reconstructive surgery (FPRS) is a key part of the curriculum for otolaryngology residents. It is important to gain an understanding of the breadth of exposure and level of competence residents feel with these concepts during their residency.

Objective To determine the level of FPRS exposure and training otolaryngology residents receive during their residency.

Methods A survey was emailed to all Accreditation Council for Graduate Medical Education (ACGME) accredited otolaryngology residents. The survey aimed to find the level of exposure to FPRS procedures otolaryngology residents get and how confident they feel with their training in cosmetic FPRS.

Results A total of 213 residents responded to the survey for an overall response rate of 13.4%. There was an even mixture of residents from all postgraduate year (PGY) levels, with 58% of respondents being male. Almost all (98%) of the residents felt FPRS was important to otolaryngology residency training. Exposure to procedures varied with 57% performing or assisting with cosmetic minor procedures, 81% performing or assisting with cosmetic major procedures, and 93% performing or assisting with reconstructive procedures. Only 49% of residents felt their programs either very or somewhat adequately prepared them in cosmetic facial plastic surgery.

Conclusion There was a wide variability in the FPRS procedure exposure. Most residents felt procedures were a vital part of otolaryngology residency training, but not all were able to participate in them. Only half of the residents felt well-prepared in cosmetic procedures.
An 86-Year-Old Female with Mitral Regurgitation and Significant Pectus Excavatum
Authors: Tasar Raphael , Tkebuchava Sophie , Diab Mahmoud , Doenst Torsten
Published: December 2019

Background We report the case of minimally invasive mitral valve repair in an 86-year-old female with symptomatic structural mitral regurgitation and severe pectus excavatum.

Case Description The case summarizes four areas of repetitive heart team discussions. First, should an 86-year-old patient still be treated invasively? Second, if so, should treatment be interventional or surgical? Third, if surgical, should we replace or repair at that age and fourth which surgical access is best with respect to her chest deformation?

Conclusion We chose to surgically repair the valve using a minimally invasive approach. The patient was extubated 3 hours after surgery and discharged after 7 days.
Biomechanical Comparison of Two Locking Plate Constructs for the Stabilization of Feline Tibial Fractures
Authors: Hottmann Natasha M. , Johnson Matthew D. , Banks Scott A. , Tuyn David , Lewis Daniel D.
Published: December 2019

Objectives The aim of this study was to compare the biomechanical characteristics of locking compression plate (LCP) and conical coupling plate (CCP) constructs for the stabilization of experimentally induced gap fractures in cat tibiae.

Materials and Methods Pelvic limbs were harvested from eight cat cadavers. Paired tibiae were stripped of all soft tissues, and randomly assigned to the LCP or CCP stabilization group. An eight-hole 2.7 mm LCP or a six-hole 2.5 mm CCP was applied to the medial surface of each tibia. A 1-cm segment of the tibia was excised centrally beneath the plate. The specimens were potted, then tested in non-destructive four-point craniocaudal and mediolateral bending, followed by non-destructive axial compression. Each construct was subsequently loaded to failure in axial compression. Bending and axial stiffness, yield load and failure load were calculated for each specimen.

Results The LCP constructs were significantly stiffer than the CCP constructs when subjected to non-destructive bending and axial loading. Craniocaudal bending stiffness was significantly greater than mediolateral bending stiffness for both constructs. Yield load and failure load were significantly greater for LCP constructs compared with CCP constructs.

Clinical Significance LCP may be a more suitable implant for stabilizing complex diaphyseal tibial fractures in cats. Additional supplemental fixation should be considered when using CCP to stabilize unreconstructed diaphyseal tibial fractures in cats. Further clinical investigation of both implants is recommended.
High-Risk Pregnancies and Their Impact on Neonatal Primary Hemostasis
Authors: Politou Marianna , Mougiou Vasiliki , Kollia Maria , Sokou Rozeta , Kafalidis Georgios , Iliodromiti Zoi , Valsami Serena , Boutsikou Theodora , Iacovidou Nicoletta
Published: December 2019

Primary hemostasis, similar to other systems in the adjusting and transitioning neonate, undergoes developmental adaptations in the first days of life. Although platelets of neonates do not differ quantitatively compared with those of adults, they functionally present with major differences, thus supporting the theory of a “hypofunctional” phenotype that is counterbalanced by high hematocrit and more potent von Willebrand factor multimers. No clinical effect of bleeding tendency has hence been established so far for healthy term neonates. However, discrepancies in functionality have been noted, associated with gestational age, with more pronounced platelet hyporesponsiveness in preterm neonates. Multiple methods of in vitro platelet function evaluation such as PFA-100/200, platelet aggregometry, flow cytometry, and cone and platelet analyzer have been used for assessment of neonatal primary hemostasis. Several pregnancies are characterized as “high-risk” when risk factors preexist in maternal history or evolve during pregnancy. These pregnancies require specialized observation as they may have unpredictable outcome. High-risk pregnancies include clinical entities such as preeclampsia, pregnancy-induced smoking during pregnancy, gestational diabetes mellitus (GDM), autoimmune diseases, and other maternal hematological conditions. In some cases, like systemic lupus erythematosus, antiphospholipid antibody syndrome, and maternal immunologically based thrombocytopenia, neonatal thrombocytopenia is regarded as a prominent hemostasis defect, while in others, like pregnancy-induced hypertension and preeclampsia, both quantitative and qualitative disorders of neonatal platelets have been reported. In other pathologies, like GDM, neonatal primary hemostasis remains vastly unexplored, which raises the need for further investigation. The extent to which primary hemostasis is affected in neonates of high-risk pregnancies is the main objective of this narrative review.
The Association of Paternal Race and Ethnicity with Adverse Pregnancy Outcomes in a Contemporary U.S. Cohort
Authors: Palatnik Anna , Garacci Emma , Walker Rebekah J. , Ozieh Mukoso N. , Williams Joni S. , Egede Leonard E.
Published: December 2019

Objective Maternal racial and ethnic disparities exist in obstetric outcomes. The contribution of paternal race and ethnicity toward obstetric outcomes has been less well documented. The objective of this study was to investigate the association between paternal race and ethnicity and several adverse pregnancy outcomes.

Study Design This was a retrospective cohort of birth data from the CDC National Vital Statistics, years 2013—2017. All singleton live births were included in the analysis. Records with missing paternal race and ethnicity were excluded. The primary dependent variables were the following adverse maternal and perinatal outcomes: gestational diabetes, hypertensive disorder of pregnancy, preterm birth <37 weeks, cesarean delivery, low birth weight <2,500 g, 5-minute Apgar's score <7, admission to neonatal intensive care unit (NICU), and assisted ventilation at > 6 hours of life. The main exposure was paternal race and ethnicity, which was grouped into non-Hispanic white, non-Hispanic black, Hispanic, and other. Other race and ethnicity category included: American Indian, Alaskan Native, Asian, Native Hawaiian, or other Pacific Islander. Univariable and multivariable analyses were done to determine whether paternal race and ethnicity was independently associated with adverse pregnancy outcomes.

Results A total of 16,482,745 births were included. In univariable analysis, all adverse obstetric outcomes were significantly associated with paternal race and ethnicity. In multivariable analysis, controlling for maternal and paternal demographic characteristics and maternal clinical factors, paternal race and ethnicity remained significantly associated with the majority of the adverse pregnancy outcomes. The strongest association was seen with: (1) paternal non-Hispanic black race and ethnicity, and higher rates of LBW and preterm birth (Odds ratio [OR] = 1.25, 95% CI: 1.24–1.27 and OR = 1.14, 95% CI: 1.13–1.15, respectively); (2) paternal Hispanic race and ethnicity and lower rates of 5-minute Apgar's score <7, and assisted ventilation at >6 hours of life (OR = 0.78, 95% CI: 0.77–0.79, and OR = 0.77, 95% CI: 0.75–0.78, respectively); and (3) other paternal race and ethnicity and higher rates of gestational diabetes, but lower rates of hypertensive disorder of pregnancy and assisted ventilation >6 hours of life (OR = 1.26, 95% CI: 1.25–1.27; OR = 0.79, 95% CI: 0.78–0.80; and OR = 0.80, 95% CI: 0.78–0.82, respectively). All associations were in comparison to paternal non-Hispanic white race and ethnicity.

Conclusion Paternal race and ethnicity has an independent association with adverse obstetric outcomes. The pathway and the extent of the paternal racial influence are not fully understood and deserve additional research.
The Distance between the Pectoralis Major Tendon Insertion and the Top of the Humeral Head is a Reliable Landmark: An Anatomic Study
Authors: Sahu Dipit , Jagiasi Jairam D. , Valavi Anisha S. , Ubale Tushar
Published: December 2019

Purpose This study aimed to analyze the distance between the superior edge of the pectoralis major and the top of the humeral head and evaluate whether this distance is a consistent measurement.

Methods Twenty-two shoulders in eleven cadavers were dissected and the attachment of the pectoralis major tendon was preserved. Two distances were recorded with the help of digital vernier caliper: the distance between the upper edge of pectoralis major and tangent to the top of humeral head (PM–T) and the distance between the superomedial tip of greater tuberosity (GT) and the upper edge of the pectoralis major tendon (PM–G; ± standard error of the means).

Results The mean PM–T distance was 53.8 mm (±0.8 mm) and the mean PM–G distance was 46.8 mm (±0.9 mm). The distance between the top of humeral head and tip of the GT was 7 mm. The PM–T distance was a significant outlier in three shoulders as it inserted high on the humerus.

Conclusion We can conclude that the PM–T and PM–G distances were a consistent measurement.

Clinical Relevance The distance between the pectoralis major tendon and top of the humeral head was measured in this study as a reliable method that can be used intraoperatively to decide the height of the humerus prosthesis in comminuted fractures of the proximal humerus.
Dry needling of the gastrocnemius muscle. Overlap between trigger point area and the presence of blood vessels
Authors: P. Velasco Fernández , F. Valera Garrido
Published: December 2019

Aims To evaluate the anatomic variability of the gastrocnemius venous system using ultrasound and the overlap of the same with myofascial trigger points (MTrPs 1 and 2) clinically located in this muscle.

Material and Methods In total, 82 legs of 41 healthy adults were studied, belonging to 26 men and 15 women aged between 22 and 50 years. The blood vessels located below MTrP1 and MTrP2, described by Travell and Simons were observed, and each image was analyzed by sectors (medial, central and lateral) to quantify the number of blood vessels, their distribution and overlap with the MTrPs described at this level.

Results Examination of the 164 heads of 82 gastrocnemius muscles revealed that at least one vessel exists for each section analyzed. The number of veins per head varied between 1 and 8. The most common pattern in the medial gastrocnemius was three vessels (41.5%) and two vessels (49%) in the lateral gastrocnemius. In 100% of the cases the localization of the veins coincided with the clinical localization of the MTrPs.

Conclusions The venous pattern of the proximal gastrocnemius is highly variable among subjects regarding the number of blood vessels and their distribution. There is a complete overlap between the clinical localization of the gastrocnemius MTrPs and the presence of blood vessels.
Application of ultrasound-guided percutaneus neuromodulation (PNM) in women with anterior knee pain
Authors: P. García-Bermejo , M. Albornoz-Cabello , B. De la Cruz-Torres
Published: December 2019

Background Anterior knee pain (AKP) is one of the most common pathologies of the lower limb, with an incidence that is 2.2% greater in women than in men. Electric currents have been used as an effective treatment for pain in many pathologies, however, the percutaneous application of the same has represented a particularly great advancement. In the field of physical therapy, ultrasound-guided percutaneous neuromodulation (US-guided PNM), is a technique that is being developed with promising results, however there is still a scarcity of studies concerning this technique.

Aim To evaluate the improvement in chronic anterior knee pain symptoms after the application of US-guided PNM on the femoral nerve of the affected side or the healthy side, in a population of women.

Material and Methods The sample comprised 15 women with chronic unilateral AKP, who were randomly divided into two groups: experimental group 1 (n = 8), who received US-guided PNM upon the femoral nerve, on the leg of the affected side, and an experimental group 2 (n = 7), who received US-guided PNM on the femoral nerve of the non-affected side. The intervention was performed using a needle measuring 0.3 × 40mm on the motor fibers of the femoral nerve under ultrasound guidance and using a monopolar electrode, with a frequency of 10 Hz and a phase duration of 250 microseconds, during 1.5 minutes. We registered active ROM in both knees, pain according to the Visual Analog Scale (VAS) and functionality using the VISA-P questionnaire and the Kujala scale. All variables were evaluated pre-intervention, post-intervention and after 24 hours.

Results No statistically significant differences were found in both groups between the pre and post intervention measurements. However, statistically significant changes were found in both groups between the pre and post intervention at 24 hours, regarding increased ROM and functionality and a decrease in pain (p < 0.05). Nonetheless, the between-group comparison did not obtain a significant difference in any of the variables studied (p > 0.05). The measurement of the effect size obtained a large clinical effect between both groups and between the pre-intervention measurement and the assessment at 24 hours.

Conclusion Treatment of chronic AKP in women, using US-guided PNM, leads to an improvement of symptoms and functionality, 24 hours after application of the same, regardless of whether it is applied on the femoral nerve of the affected leg or on that of the healthy leg.
Infrared thermography: usefulness in treatment with percutaneous needle electrolysis in cesarean section treatment. A case study
Authors: D. Álvarez Prats , O. Carvajal Fernández , S. Jiménez Sánchez
Published: December 2019

Background and Aim In Spain, one out of every four births is a cesarean delivery and in most cases complications occur such as adhesions. Adhesions may cause functional problems, as well as psychological and esthetic problems, such as pain and itchiness.

A correct scarring restores connections and replaces the lost tissue, preserving esthetics and functionality. The final change in tissue tone will be responsible for the correct reestablishment of the vascular network. If this does not occur correctly, we may encounter situations with a high level of hypervascularization (hypothermic areas) and the probability of generating fibrosis. Infrared thermography (IT) is a complementary imaging test which is able to capture the infrared radiation emitted by the human body and transform this information into a thermal image. There is proportionality between skin temperature and skin blood flow, therefore, the thermal images provide us with information on skin blood flow. These data are then used to identify the areas of hypervascularization or local inflammation.

Aims The aim of this study was to evaluate whether scar tissue has a different temperature to the surrounding tissue, also to detect areas of hyperthermia (hipervascularization) and apply percutaneous needle electrolysis (PNE) using thermography as a tool for assessment and monitoring.

Material and Methods A case study of a woman aged 34 years with two cesarean section scars, the last of which took place 6 months before.

Four sessions of PNE were performed using IT as a method to identify treatment points, with a time interval of 21 days between each application. Via infrared thermography, the scar area was assessed and the points where a greater temperature was registered were marked. Subsequently, the PNE technique was applied, performing 3 impacts with a duration of 3 seconds and with an intensity of 4 mA in each point marked. The intervention procedure was performed under ultrasound guidance, based on a transverse section of the scar and positioning the needle on the long axis, at a 45° tilt from the skin. The Visual Analog Scale (VAS) was registered in the first and last session.

Results After the performance of PNE on the hyperthermic points of the scar, the VAS decreased from 5 points to 0 and both the mean scar temperature in relation to the surrounding tissue improved, also, there was a reduction of the hyperthermic points.

Conclusion Infrared thermography may be a complementary imaging tool for finding alterations in the mean temperature of a scar tissue and identifying hyperthermic points which are a therapeutic target in the treatment with PNE. Besides, it could become a follow-up tool to monitor the evolution of the temperature of the scar, and therefore the effectiveness of the treatment applied. Despite the results obtained in this case, further studies are required.
Effect of ultrasound-guided percutaneous neuromodulation in ankle instability: a case study
Authors: M. Rodríguez Rosal , A. Sánchez Sixto , F. Álvarez Barbosa , A. Yáñez Álvarez
Published: December 2019

Background and Aims Ankle proprioception can be tested in many ways. Some studies have found improvements in individuals with chronic ankle instability after receiving treatment and training proprioceptive acuity and speed. Currently, there is a scarcity of evidence concerning percutaneous neuromodulation. The first findings were reported in the post-surgical stage after total knee arthroplasty and in neural improvements and symptoms in patients with hyperactive bladder.

Aim To evaluate the effectiveness of percutaneous neuromodulation on the tibial nerve for the improvement of various proprioception parameters in patients with chronic ankle instability.

Material and Methods Five men (age: 24.8 ± 4.9 years; height: 1.78 ± 0.08 m; weight: 86 ± 9.8 kg) with chronic ankle instability, who regularly practiced sports activities participated in the present study. People who had undergone an injury in the previous three months were excluded from the speed. Currently, there is a scarcity of evidence concerning test before and immediately after percutaneous neuromodulation. A single leg balance test was performed with eyes open and closed, maintaining the single-legged position on a force plate during 30 seconds (Accupower; AMTI, Watertown, MA) registering 1000 Hz. The displacement of the center of pressure (DOT) was determined based on the distances of its antero-posterior axes (DOT_AP) and medio-lateral (DOT_ML). Furthermore, the amplitudes of anteroposterior and mediolateral displacement were evaluated (ACPap and ACPml). The posterior tibial nerve was stimulated under ultrasound guidance using a 100 Vpp current, with a pulse width of 250 μs and a repetition frequency of 2 to 10 Hz. The process was performed on three occasions during 30 seconds, with an intensity that was acknowledged by the patient but which did not go beyond a score of 3 in the visual analog scale (VAS). The means and standard deviations were calculated for all variables. The effect size was calculated establishing the confidence interval at 90% and the probability of the change being significant was qualitatively calculated.

Results A decrease was found in the ACPap (Pre-test eyes open: 5.42 ± 0.62 and eyes closed: 15.99 ± 0.60; Post-test eyes open 4.05 ± 0.36 and eyes closed 10.33 ± 0.49) after the neuromodulation intervention on the tibial nerve. This was a significant change and a “possible” effect size was found in the closed eyes condition (-0.54; ± 0.72), according to Hopkins. For the remaining variables, no significant differences were observed.

Conclusions A decreased displacement of the center of mass was found in the antero-posterior axis after performing the neuromodulation technique on the tibial nerve in patients with chronic ankle instability.
Pain pressure thresholds for evaluating myofascial pain in the equine brachiocephalicus muscle
Authors: M. Calatayud-Bonilla , M. Resano-Zuazu , E. Segura-Ortí
Published: December 2019

Introduction Myofascial pain is one of the most common musculoskeletal pathologies in humans, with the presence of myofascial trigger points (MTrPs). A MTrP is defined as a hyperirritable nodule in a taut band of musculoskeletal fibers. The pain pressure threshold is a tool for the assessment of pain used in humans with proven reliability, however there is no evidence of the same in the study of MTrPs in horses.

Aims The aim of this study was to evaluate the reliability of the measurement of pressure pain sensitivity in horses with MTrPs in the brachiocephalicus muscle. A second aim was to calculate the minimum detectable change (MDC) for this result.

Material and Methods Twenty horses were evaluated, aged between five and fifteen years old. All without pathology or previous pharmacological treatment. The cranial angle of the scapula was taken as the anatomic reference. A first evaluator, whose reliability was already confirmed, performed a manual palpation of the distal aspect of the brachiocepalicus muscle. A MTrP was located in all animals included in the study. The anatomic reference and the MTrP were marked. The pain pressure threshold of the MTrP was measured using a pressure algometer (Wagner Instruments, EE.UU., kg/cm2). The same evaluator applied the tip of the algometer parallel to the neck and transversal to the muscle fibers, gradually increasing pressure until the ‘jump sign’ or facial expressions of pain were detected by a second operator who also recorded the measurements. The measurements were repeated consecutively twice in this manner. The first operator was blind to the measurements. The intraclass correlation index (ICC) was calculated to evaluate reliability.

Results The mean thresholds of pain pressure sensitivity registered for the first and second measurement were 3.29 (1.0) kg/cm2 and 3.31 (0.9) kg/cm2. The ICC was 0.86 (95% CI: 0.68 to 0.95). The MDC was 0.9 kg/cm2 (95% CI: 0.6 to 1.4).

Conclusions Acceptable reliability was found for the measurement of the pain pressure threshold in horses with MTrPs in the brachiocephalicus muscle.
Responsibility in dealing with genetic risk information
Authors: Wöhlke Sabine , Perry Julia
Published: December 2019

Predictive testing information raises questions about risk communication, health responsibility, and about how to deal with the gap between knowledge of risks and options to act on this knowledge. For some diseases identified by predictive testing, specific treatments or interventions are available, while other diseases, thus far, remain untreatable or unpreventable; this triggers different forms of responsibility. Gender also often intersects with moral responsibility, regarding risk communication but also responsibilities of care which may become necessary with a family member’s onset of disease. The aim of the study was to analyze laypeople’s attitudes towards predictive testing with a special focus on forms of responsibility arising while dealing with uncertainty of risk information. We conducted seven focus groups with laypeople (n = 43) in four German cities in 2016. Participants were provided with different genetic testing scenarios (breast cancer, early-onset Alzheimer’s disease, pharmacogenetics in rectal cancer) for discussing their responsibilities and risk perceptions. We identified three different forms of responsibility: self-responsibility and self-care, family responsibility and care for others, and professional responsibility. For laypeople, the decision for predictive genetic testing seems voluntary and free from external constraint; however, both family and professional conditions influence an individual’s decision.
Characteristics of miniature pulsed penning ion source: Experiment and PIC simulation
Authors: Mamedov N. V. , Rohmanenkov A. S. , Zverev V. I. , Maslennikov S. P. , Solodovnikov A. A. , Uzvolok A. A. , Yurkov D. I.
Published: December 2019

In the present work, the results of the experimental and particle in cell (PIC) simulation studies of the discharge combustion modes in a miniature Penning ion source (PIS) under the pulse-periodic power supply conditions are presented. Dynamics of discharge ignition and discharge operation mode at a pulsed anode voltage supply are investigated for different values of anode voltage and gas pressure in various magnetic field configurations. Typical examples of current pulse waveforms are shown. Also, numerical simulations of the PIS were performed using 3D PIC combined with Monte Carlo collisions in the code VSim. Temporal dependencies of electron, ion, and potential distributions in the Penning cell are simulated. Differences between the numerical and experimental results are discussed.
Subgrid-scale model for large-eddy simulation of transition and turbulence in compressible flows
Authors: Zhou Hao , Li Xinliang , Qi Han , Yu Changping
Published: December 2019

This article focuses on a subgrid-scale (SGS) eddy viscosity model based on helicity which is derived from our previous research [Yu et al., “Subgrid-scale eddy viscosity model for helical turbulence,” Phys. Fluids 25, 095101 (2013)] for large-eddy simulation of transition and turbulence in compressible flows. Based on the character of the compressible boundary layer over a flat plate, we obtain from theoretical analysis that this model can automatically distinguish laminar flow and turbulence and can also simulate turbulence well. Meanwhile, an a priori test using direct numerical simulation (DNS) data of a spatially developing flat-plate boundary layer at Ma = 2.25 shows that the helicity model can clearly differentiate laminar, transitional, and turbulent regions. Comparing the numerical simulation results with DNS and other SGS models in the spatially developing boundary-layer over a flat plate, we find that the suggested model could precisely predict the onset of transition, transition peak, skin-friction coefficient, mean velocity profile, mean temperature profile, and turbulence intensities. In the case of a compression ramp, the model can well simulate the bypass-type transition, the separated and reattached points, and the size of the separation bubble in the corner region. Furthermore, the prominent advantage of the proposed model can predict transitional flow exactly with no explicit filtering or dynamic procedure.
Preliminary design of diagnostic system for negative neutral beam injector at ASIPP
Authors: Xu Yongjian , Hu Chundong , Liang Lizhen , Xie Yahong , Jiang Caichao , Wei Jianglong , Tao Ling , Xie Yuanlai
Published: December 2019

According to the latest physics design of the China Fusion Engineering Test Reactor (CFETR), two neutral beam injectors (NBIs), which deliver a total of 40 MW in not less than 3600 s with 1 MeV D0, are demanded to support current drive and plasma rotation. To minimize the risks and time to provide the CFETR with reliable NBIs, a negative NBI test facility will be developed at the Institute of Plasma Physics, Chinese Academy of Science. Its mission is to understand the characteristics of the RF driven ion source and negative ion generation and extraction and to improve RF efficiency and beam quality. In order to achieve this goal, a set of diagnostic tools will be used in this test facility. For source diagnostics, optical emission spectroscopy, cavity ring-down spectroscopy, laser absorption spectroscopy, and electrostatic probes are planned to be used. Beam emission spectroscopy, W-wire calorimeters, 1D carbon fiber composite diagnostic calorimeters, beam dump with thermocouples, and water-flow calorimetry are used to assess the beam properties. The design of the diagnostic system is presented.
Using repetitive paired-pulse transcranial magnetic stimulation for evaluation motor cortex excitability
Authors: Torii Tetsuya , Sato Aya , Iwahashi Masakuni , Iramina Keiji
Published: December 2019

In this study, we investigated the effects of repetitive paired-pulse transcranial magnetic stimulation (TMS) on the motor cortex excitability. The interstimulus intervals (ISIs) between the conditioning (first) stimulus and test (second) stimulus were 1,000, 200 and 100 ms. A total of 20 stimuli were delivered to the primary motor cortex using paired-pulse TMS at 10 s intervals, and the intensity of the magnetic stimulus was 110% of the resting motor threshold for each subject. For all ISIs, there was no significant correlation between the number of stimuli and the motor evoked potential (MEP) amplitude. However, there was slight correlation between the number of stimuli and the MEP amplitude in the 200 and 100 ms ISIs (200 and 100 ms ISIs: approximately r = −0.40; 1,000 ms ISI: r = −0.17). In addition, MEP amplitude increased during the second paired pulse stimulation when an ISI of 200 ms was used, but it decreased dramatically when an ISI of 100 ms was used. In contrast, MEP amplitude did not change significantly when a 1,000 ms ISI was employed. Therefore, 10 consecutive paired-pulse TMS stimuli with a 1,000 ms ISI may not have a cumulative effect on cortical excitability. Previous studies used a long duration (e.g., 6 minutes or longer by 0.1 Hz magnetic stimulation) of magnetic stimulation to evaluate cortical excitability. In evaluating cortical excitability by magnetic stimulation, it is important to shorten the period to reduce the subject’s burden and to prevent body movement. Thus, our present findings suggest that repetitive paired-pulse TMS with an ISI of 1,000 ms is suitable for the rapid evaluation of cortical excitability.
The impact of nano-bubbles on the laser performance of hafnia films deposited by oxygen assisted ion beam sputtering method
Authors: Harthcock C. , Qiu S. R. , Negres R. A. , Hammons J. A. , Voisin T. , Guss G. , Martin A. A. , Stolz C. J. , Menor M. G. , Bhowmik G. , Huang M.
Published: December 2019

Hafnia is a high refractive index material used in the manufacturing of dielectric coatings for next generation lasers. The formation of defects during deposition is the major barrier to realizing high laser-damage resistant coatings for future high energy density laser applications. Understanding the precursors responsible for laser-induced damage in hafnia is therefore critical. In this work, we investigate the mechanism of laser-induced damage in 90-nm thick hafnia films produced by an oxygen assisted dual ion beam sputtering (IBS) process. Under pulsed, nanosecond ultraviolet laser exposure (355 nm, 8 ns), the laser-induced damage onset is found to be strongly dependent on the amount of argon and excessive oxygen entrapped in the nanobubbles within the hafnia films. The presence of nanobubbles is revealed and confirmed by small angle X-ray scattering and scanning/transmission electron microscopy coupled with high-angle annular dark-field. The damage onset is stable initially but decreases as the energy of oxygen goes beyond 100 eV. The damage initiation is ascribed to a laser-induced plasma generation within the nanobubbles through multiphoton ionization. The results reveal that nanobubbles formed in the IBS produced coatings are a potent precursor. Although nanobubbles are commonly present in IBS films, their negative impact on laser damage resistance of hafnia films has not been previously recognized. Our findings provide a fundamental basis for the development of potential mitigation strategies required for the realization of laser damage resistant hafnia films.
An apparatus based on an atomic force microscope for implementing tip-controlled local breakdown
Authors: St-Denis T. , Yazda K. , Capaldi X. , Bustamante J. , Safari M. , Miyahara Y. , Zhang Y. , Grutter P. , Reisner W.
Published: December 2019

Solid-state nanopores are powerful tools for sensing of single biomolecules in solution. Fabrication of solid-state nanopores is still challenging, however; in particular, new methods are needed to facilitate the integration of pores with larger nanofluidic and electronic device architectures. We have developed the tip-controlled local breakdown (TCLB) approach, in which an atomic force microscope (AFM) tip is brought into contact with a silicon nitride membrane that is placed onto an electrolyte reservoir. The application of a voltage bias at the AFM tip induces a dielectric breakdown that leads to the formation of a nanopore at the tip position. In this work, we report on the details of the apparatus used to fabricate nanopores using the TCLB method, and we demonstrate the formation of nanopores with smaller, more controlled diameters using a current limiting circuit that zeroes the voltage upon pore formation. Additionally, we demonstrate the capability of TCLB to fabricate pores aligned to embedded topographical features on the membranes.
Study of static and dynamic properties of planar dumbbell shaped structure of Ni80Fe20
Authors: Khanal Shankar , Sherpa Pemba , Spinu Leonard
Published: December 2019

In this work, planar symmetric (Dot) and non-symmetric (Nanowire) structures were combined to fabricate the modulated planar structures (Dumbbell) of Ni80Fe20. Four set of samples were fabricated on top of the signal line of coplanar waveguides with dumbbell’s axis along and perpendicular to it using methods of photolithography, electron beam lithography and liftoff. The diameter of the dots was varied to study the effect on both static and dynamic properties of modulated structures. The static magnetization reversal was investigated by NanoMOKE measurements, whereas broadband ferromagnetic resonance spectroscopy was carried out to probe the dynamic properties in GHz range. Micromagnetic simulations were performed to comprehend the experimental results in detail.
Magnetic characterization change by solvents of magnetic nanoparticles in liquid-phase magnetic immunoassay
Authors: Jinno Katsuya , Hiramatsu Bunta , Tsunashima Kenta , Fujimoto Kayo , Sakai Kenji , Kiwa Toshihiko , Tsukada Keiji
Published: December 2019

Liquid-phase magnetic immunoassay (MIA) using magnetic nano-particles (MNPs) has been studied as a more rapid method compared to optical methods for inspecting proteins and viruses. MIA can estimate the number of conjugated antibodies without being washed differently from conventional optical immunoassay. However, in the case of the liquid phase, it is considered that the magnetic properties of MNPs are affected by physical properties such as viscosity and impurity substances such as biological substances contained in the blood. In this study, the effect of sodium chloride (NaCl) in buffer and serum solution was evaluated to reveal the effect of serum because the sodium (Na+) and chloride (Cl-) ions in the serum dominate ion balance of blood. The measurement results of AC magnetic susceptibility and a dynamic light scattering (DLS) showed that the aggregation of MNPs was largely affected by the concentration of NaCl. This effect of the NaCl could be explained by shielding of the surface charge of MNPs by ions in the solution. Although the concentrations of NaCl in the buffer and serum solution were almost same, we found that MNPs were aggregated more in their size for those in the serum solution because of other impurities, such as proteins. These results suggest evaluation of effects of the contaminants in serum and optimization of polymer coatings of MNPs could be important factors to realize measurements of magnetic immunoassay with high accuracy.
Tape in the cloud—Technology developments and roadmaps supporting 80 TB cartridge capacities
Authors: Fontana R. E. , Biskeborn R. G. , Lantz M. , Decad G. M.
Published: December 2019

Tape, which is the storage of magnetic bits on flexible 0.5” wide media, provides critical data storage needs for the Cloud as evidenced by continued growth in exabyte shipments of tape products. This paper outlines the present storage landscape environment for tape, HDD, and NAND flash, describes the tape roadmap for capacity improvements, and presents recording data on narrow track, 32 channel, TMR tape heads spanning read sensor widths from 1.0 μm to 0.20 μm illustrating the potential for 80 TB cartridge operation. Critically, future improvements in tape areal density and tape cartridge capacity are expected to be achieved from evolutionary developments in head/media technology, not requiring revolutionary developments, such as energy assisted magnetic recording technologies required by HDD strategies.
Investigation of the Dyakonov-Shur instability for THz plasma waves in quantum gated cylindrical FET
Authors: Li Dongao , Zhang Liping , Su Junyan
Published: December 2019

Plasma waves may become unstable in the channel of field effect transistors (FETs) with asymmetric boundary conditions on source and drain, which is known as Dyakonov-Shur instability. In this letter, we extend the Dyakonov-Shur instability to the quantum gated cylindrical FET and obtain the dispersion equations describing unstable terahertz (THz) plasma waves using quantum cylindrical hydrodynamic equations. Research results show that the length of the channel and the wave vector of the circumferential direction inhibit the instability increment; however, the quantum effect, the radius of the channel, and the electron temperature enhance the instability increment. The oscillation frequency increases with the increase in the quantum effect, the wave vector of the circumferential direction, and the electron temperature, but the oscillation frequency increases with the decrease in the length and radius of the channel. Compared with the one-dimensional rectangular FET, THz plasma waves in the two-dimensional cylindrical FET have a higher oscillation frequency.
Randomness at large numbers: Experimental proof in coin toss and prime number
Authors: Kim Yeseul , Weon Byung Mook
Published: December 2019

Randomness is a central concept to statistics and physics. Here, we conduct experimental investigations with a coin toss and prime number to show experimental evidence that tossing coins and finding last digits of prime numbers are statistically identical with respect to equally likely outcomes. The range of frequency of an outcome (R) is normalized by the total number of repetitions (N) to be the range of relative frequency (R/N). We find that R/N has a power-law scaling R/N ∼ N−0.6, which is valid for large numbers in both cases of a coin toss and the last digit of a prime number. This analysis, indicating R/N → 0 at N → ∞, confirms that randomness and equally likely outcomes can be valid for large numbers.
Effects of the diploidisation process upon the 5S and 35S rDNA sequences in the allopolyploid species of the Dilatata group of Paspalum (Poaceae, Paniceae)
Authors: Vaio Magdalena , Mazzella Cristina , Guerra Marcelo , Speranza Pablo
Published: December 2019

The Dilatata group of Paspalum includes species and biotypes native to temperate South America. Among them, five sexual allotetraploids (x = 10) share the same IIJJ genome formula: P. urvillei Steud, P. dasypleurum Kunze ex Desv., P. dilatatum subsp. flavescens Roseng., B.R. Arrill. & Izag., and two biotypes P. dilatatum Vacaria and P. dilatatum Virasoro. Previous studies suggested P. intermedium Munro ex Morong & Britton and P. juergensii Hack. or related species as their putative progenitors and donors of the I and J genome, respectively, and pointed to a narrow genetic base for their maternal origin. It has not yet been established whether the various members of the Dilatata group are the result of a single or of multiple allopolyploid formations. Here, we aimed to study the evolutionary dynamics of rRNA genes after allopolyploidisation in the Dilatata group of Paspalum and shed some light into the genome restructuring of the tetraploid taxa with the same genome formula. We used double target fluorescence in situ hybridisation of 35S and 5S rDNA probes and sequenced the nrDNA internal transcribed spacer (ITS) region. A variable number of loci at the chromosome ends were observed for the 35S rDNA, from 2 to 6, suggesting gain and loss of sites. For the 5S rDNA, only one centromeric pair of signals was observed, indicating a remarkable loss after polyploidisation. All ITS sequences generated were near identical to the one found for P. intermedium. Although sequences showed a directional homogeneisation towards the putative paternal progenitor in all tetraploid species, the observed differences in the number and loss of rDNA sites suggest independent ongoing diploidisation processes in all taxa and genome restructuring following polyploidy.
The morphological characteristics and germination of grassland forb species after simulated digestion by sheep in the Tianshan Mountains, China
Authors: Che Z. B. , Wang S. L. , Lu W. H. , Jin S. F. , Chen Y. S. , Li N. N. , Sun H. R.
Published: December 2019

Viable seeds from dry-fruited forbs growing in the Tianshan Mountains of China are often found in livestock dung. However, the effect of ingestion on their morphological characteristics and germination remains unclear. This research assessed the germination of 15 forbs after simulated ingestion (insertion through a rumen fistula) by Kazakh sheep. Seed accessory structures (such as wings, trichomes and mucilage) were digested. Seed length, width and thickness were negatively correlated with digestion time, and 100-seed mass was negatively (but not significantly) correlated with digestion time. The means of seed morphological traits (except for the seed shape index) and germination generally decreased. Germination was negatively correlated with digestion time. Germination of Rumex acetosa, Leontice incerta and Lonicera hispida initially increased and then decreased with increased digestion time, while germination of the other 12 seeds all significantly decreased with increased digestion time. Germination of Plantago depressa, Alyssum desertorum, Lachnoloma lehmannii, Tulipa gesneriana, Tauscheria lasiocarpa and Calligonum rubicundum decreased to zero after 24h digestion, whereas the other nine seeds still had some level of vigour. Seeds of several forbs survived rumen digestion, indicating the potential for endozoochorous seed dispersal, a dispersal mechanism known to enhance survival in dynamic and harsh desert habitats.