Search

Staphylococcus aureus - both meticillin-resistant S. aureus (MRSA) and meticillin-susceptible S. aureus (MSSA) - is a major cause of neonatal infections. Infection control measures have not lowered the incidence of MSSA infections to the same degree as that of MRSA infections.To investigate the transmission pathway of MSSA in neonatal intensive care unit (NICU) using genetic analysis.Neonatal patients, their parents, and healthcare workers were swab-tested in the NICU at our hospital at the time of hospitalization and then every month thereafter from October 1There were 16 MSSA-positive patients. Four MSSA-positive patients shared strains from the same phylogenetic groups as those of healthcare workers. One presented the same strain as the parent. MSSA-positive twin neonates shared the same strain. Ten had sporadic strains; 32 of the 97 tested healthcare workers were MSSA positive.The findings of this study suggest that the route of transmission of MSSA in NICU may be through MSSA in the hospital environment in addition to horizontal transmission via healthcare workers. Along with hand hygiene with alcohol, thorough environmental maintenance and parental education are important for infection control in NICUs targeting MSSA.

Study question Does the post-thaw use of a GM-CSF-containing medium improve blastocyst transfer outcomes in all blastocysts in a frozen-thawed embryo transfer cycle? Summary answer The use of a GM-CSF-containing medium at post-thawing especially improves the live birth (LB) rate of morphologically poor blastocysts in a frozen-thawed embryo transfer cycle. What is known already GM-CSF, a cytokine secreted by the epithelial cells of the female reproductive tract, plays an important role in embryonic development, implantation, and subsequent development in humans and animals. In humans, GM-CSF increases the blastocyst developmental rate and decreases the chances of miscarriage. Previously, we reported that the use of a GM-CSF-containing medium for blastocyst recovery culture after thawing improves the clinical pregnancy (CP) rate in a frozen-thawed blastocyst transfer cycle (ESHRE, 2019). However, it is unclear whether GM-CSF improves embryo transfer outcomes in all blastocysts. In addition, it is necessary to accumulate information regarding its effects on neonatal outcomes. Study design, size, duration We performed a retrospective observational study to compare two groups: a GM-CSF group (GM-CSF-containing medium; SAGE-1step GM-CSF, Cooper Surgical) and a control group (GM-CSF-free medium; ONE STEP Medium, NAKA Medical). We analyzed 566 blastocyst transfer cycles in patients aged 30–39 years who underwent frozen-thawed single embryo transfer at Takahashi Women’s Clinic (Japan) from February 2018 to February 2019. Chromosomal analysis was not performed. Participants/materials, setting, methods We used a control medium for blastocyst culture and a Cryotop safety kit for blastocyst vitrification. After thawing, we cultured blastocysts in a GM-CSF-containing medium or control medium for 3–5 h until transfer. Embryo transfer outcomes were compared. We performed the multivariate logistic regression analysis(MVRA) to adjust confounding bias. A subgroup analysis was also performed of morphological grade according to Gardner’s criteria (excellent: ≥AA, good: blastocysts containing B, poor: blastocysts containing C). Main results and the role of chance There were no difference in patient background between the two groups. The CP and LB rates in the GM-CSF group and control group were 54.3% vs. 42.6% and 42.9% vs. 31.1%. The MVRA adjusted by confounding factors(patient age, BMI, basal AMH, blastocyst grade, day of vitrification, number of previous failed ETs, and assisted hatching) demonstrated that CP (p = 0.0193; adjusted odds ratio [aOR], 1.55) and LB rate (p = 0.0080; aOR, 1.67) were significantly higher in GM-CSF group than that of control group. Moreover, the CP and LB rates of the GM-CSF group and control group were: excellent-blastocysts at 62.0% vs. 58.8% (p = 0.5955; OR, 1.14), 52.7% vs. 45.6% (p = 0.2466, aOR:1.33), good-blastocysts 52.1% vs. 37.6% (p = 0.0561; OR, 1.80), 38.0% vs. 26.6% (p = 0.1072; OR, 1.69), and poor-blastocysts 38.9% vs. 17.9% (p = 0.0115; OR, 2.92), 25.9% vs. 9.0% (p = 0.0164; OR, 3.56). A GM-CSF-containing medium significantly improved the CP and LB rates of poor-grade blastocysts. There were no significant differences between the GM-CSF group and control group in the male ratio (52.7％ vs. 51.0%, p = 0.8057), pregnancy duration (38.8±1.4 weeks vs. 38.5±1.8 weeks, p = 0.2558), cesarean section rate (38.2% vs. 40.8%, p = 0.6979), birth weight (3133±466g vs. 3037±437g, p = 0.1281), and congenital anomaly rate (0.91% vs. 2.04％, p = 0.6026). Limitations, reasons for caution This was a single-center, retrospective study. Chromosomal abnormalities in embryos were not considered; however, the LB rate among babies was analyzed. The basic chemical composition of the culture medium (salt concentration, glucose concentration, etc.) used in the control group was different from that of the GM-CSF-containing medium. Wider implications of the findings We found that the use of a GM-CSF-containing medium improved the clinical pregnancy and live birth rates of poor-grade blastocysts without affecting the babies. This may be an effective therapeutic strategy for some patients as it may allow for the effective use of poor-grade euploid blastocysts. Trial registration number not applicable

Study question This study aimed to analyze whether hyaluronan as an alternative to polyvinylpyrrolidone (PVP) for sperm immobilization, aspiration, and injection into the ooplasm improves ICSI outcomes. Summary answer The use of hyaluronan solution as an alternative to PVP improves the blastocyst formation rate and good quality blastocyst formation rate compared to PVP. What is known already The PVP solution facilitates ICSI procedures, such as sperm immobilization, aspiration, and injection into the ooplasm. However, it has been reported that injection of a small amount of PVP along with the sperm into the ooplasm negatively affects subsequent embryo development. Hyaluronan is a natural component of the extracellular matrix of the cumulus-oocyte complex. Balaban et al. (2003) reported that hyaluronan can replace PVP during ICSI procedures in the early embryo transfer cycle without adversely affecting pregnancy outcomes. This study analyzed whether using hyaluronan-based solution for the ICSI procedure would improves blastocyst development compared with ICSI using PVP. Study design, size, duration This retrospective study analyzed clinical medical reports at Takahashi Women’s Clinic, Japan. We included 4002 oocytes retrieved from 411 patients under 39 years of age who underwent ICSI using autologous oocytes between December 2019 and August 2021. Of the oocytes used for ICSI, 1909 underwent sperm aspiration and injection into the ooplasm with hyaluronan (Sperm Slow; Origio), and 2093 oocytes with 7% PVP (NakaMedical). We did not perform preimplantation genetic testing-aneuploidy for any cycles. Participants/materials, setting, methods We used PVP droplets for sperm selection under 400× magnification in both groups. In hyaluronan-ICSI, the selected sperm were transferred to a hyaluronan droplet and washed three times. The sperm was then aspirated with hyaluronan, and ICSI was performed. In PVP-ICSI, all procedures were performed using PVP. The ICSI and embryo transfer outcomes were compared between hyaluronan-ICSI and PVP-ICSI by logistic regression analysis considering patient age, BMI, and basal level of anti-mullerian hormone. Main results and the role of chance Normal fertilization rates were 74.3% (1556/2093) in PVP-ICSI and 75.5% (1442/1909) in hyaluronan-ICSI. There was no significant difference in the normal fertilization rate between PVP-ICSI and hyaluronan-ICSI groups (p = 0.437, aOR:1.06, 95% CI: 0.92–1.22). We cultured 1323 2PN embryos in PVP-ICSI and 1237 2PN embryos in hyaluronan-ICSI until the blastocyst stage. Blastocyst formation rates were 48.1% for PVP-ICSI and 52.3% for hyaluronan-ICSI, and this difference was statistically significant (aOR, 1.20; 95% CI: 1.02–1.40; p = 0.024). Moreover, the good grade (Gardner criteria ≧BB) blastocyst formation rates were significantly higher in the hyaluronan-ICSI group (36.9% and 41.0%, aOR: 1.21, 95% CI: 1.03–1.42, p = 0.022). During the study period, we performed 163 and 169 cryo-thawed blastocyst transfer cycles in PVP-ICSI and hyaluronan-ICSI, respectively. The clinical pregnancy rate (50.9% vs. 54.4%, aOR: 1.19, 95% CI: 0.77–1.83, p = 0.443) and miscarriage rate (19.3% vs. 13.0%, aOR: 0.66, 95% CI: 0.3–1.44, p = 0.295) after embryo transfer were not significantly different between PVP-ICSI and hyaluronan-ICSI. Limitations, reasons for caution The study was conducted at a single IVF center, and the oocytes included in this study were collected from patients aged < 39 years. Embryo transfer result is based on ongoing pregnancy, while the live birth data for all pregnancies are not yet available. Wider implications of the findings Hyaluronan facilitates ICSI procedures such as sperm immobilization, aspiration, and injection. Moreover, the hyaluronan improves blastocyst development. The present study indicates that using hyaluronan as an alternative to PVP during the ICSI procedure is recommended. Trial registration number not applicable

Background/Introduction Smoking is known to induce systemic vascular damage, leading to cardiovascular diseases. Recent studies demonstrated that central blood pressure has a greater impact on cardiovascular events than brachial blood pressure. Purpose We investigated influences of habitual smoking on central systolic blood pressure (CSBP) in hypertensive subjects. Methods A total of 5630 subjects (male = 2622, 51.7±12.0 year-old at baseline), who visited our hospital for a physical check-up at least twice during the last 10 years and underwent CSBP measurement at each visit, were enrolled, and they were divided into three groups; normotensive (n=4634), non-treated hypertensive (n=91) and treated hypertensive subjects (n=905). Then, the influences of smoking on the average and yearly changes of CSBP (median follow-up 5 years) were analyzed. Brachial blood pressure (oscillometer) and radial artery pressure waveforms (tonometer) were recorded using an automated device, and the pressure corresponding to the second systolic peak of radial pressure waveforms was taken as CSBP (HEM-9000AI, Omron Healthcare, Kyoto). Hypertension was defined as brachial BP ≥140/90mmHg or the use of antihypertensive medications. A yearly change in CSBP was calculated in each subject by linear regression analysis using longitudinal data. Results The average CSBP was higher in habitual smokers than in non-smokers when analyzed in normotensive (109.1±11.7 vs. 107.6±12.8 mmHg, p Conclusions Habitual smoking increases CSBP, however, antihypertensive medications counteract the unfavorable effects of smoking on CSBP. These results imply a new pathway underlying the development of cardiovascular diseases in smokers. Unfavorable changes in the cardiovascular system caused by smoking may quite slowly progress that short period of observation in the present study could not have detected enhanced yearly increases of CSBP by smoking. Funding Acknowledgement Type of funding sources: None.

Background The current system of HeartFlow fractional flow reserve derived from computed tomography (FFRCT) is not available for stented coronary arteries. However, the latest version of HeartFlow FFRCT has the potential of rendering an accurate assessment for stented coronary arteries. Objectives To evaluate the feasibility of FFRCT for the stented coronary arteries. Methods We retrospectively enrolled patients with a history of coronary stent implantation who underwent invasive fractional flow reserve (FFR) for the stented coronary arteries within 3 months after coronary computed tomographic angiography (cCTA). As a subgroup analysis, we analyzed optical coherence tomography (OCT) images in patients who underwent OCT for stented vessels. OCT was performed as a part of the Kobe University Hospital OCT registry, which is a single-centre registry of consecutive patients who underwent OCT for the coronary arteries. The diagnostic performance of HeartFlow FFRCT for stented vessels was evaluated by comparing with that of cCTA alone. Minimum lumen area (MLA) within stent segments derived from cCTA was also compared with MLA derived from optical coherence tomography (OCT). Results A total of 30 vessels in 23 patients were studied. The diagnostic accuracy, sensitivity, specificity, positive and negative predictive value of FFRCT for myocardial ischemia using invasive FFR as a reference standard was 73.3%, 88.9%, 67.7%, 53.3% and 93.3%, respectively. FFRCT provided superior diagnostic performance than cCTA alone (p=0.016). FFRCT was significantly correlated with the invasive FFR (r=0.620, p Conclusions The latest version of the HeartFlow FFRCT has the potential to be available for stented coronary arteries. Further investigation is required to elaborate our results. Funding Acknowledgement Type of funding sources: None. Figure 1Figure 2

Study question Can a scoring model based on morphokinetic data developed to predict pregnancy rates of day–5 blastocyst transfers (KIDSCORE™D5) predict pregnancy rates of day–6 blastocyst transfers? Summary answer KIDSCORE™D5 was able to predict the clinical pregnancy rates of embryo transfers done on day 6 with an area under the curve (AUC) of 0.72. What is known already KIDSCORE™D5 is a scoring model based on morphokinetic data developed to predict the pregnancy rates of day–5 blastocysts. In 2019, Regnier et al. reported that the AUC of KIDSCORE™D5 for predicting clinical pregnancy rates of day–5 blastocyst transfers was 0.6. However, as KIDSCORE™D5 is constructed based on morphological characteristics and developmental dynamics of day–5 blastocysts, it is unclear whether KIDSCORE™D5 can predict pregnancy rates of day–6 blastocyst transfers. Since there are many cases of day–6 blastocyst transfers, it is important to know if KIDSCORE™D5 can predict pregnancy rates of day–6 blastocyst transfers. Study design, size, duration This retrospective single-center study, which included 162 day–5 and 72 day–6 blastocyst transfers, respectively, was conducted at Takahashi Women’s clinic from January to December 2019. Blastocysts derived from 146 patients who underwent intracytoplasmic sperm injection. All blastocysts were cryopreserved and were transferred singly. Participants/materials, setting, methods We used EmbryoScope+™ (Vitrolife) for in-vitro culture and calculated KIDSCORE™D5 (ver.3) using Embryoviewer™ (Vitrolife). Blastocyst scoring was done from 1.0 to 9.9. Clinical pregnancy was defined as the presence of a gestational sac confirmed by transvaginal ultrasonography. Statistical analysis was performed with JMP Pro 15.00 (SAS). The relationship between KIDSCORE™D5 and clinical pregnancy was evaluated by the AUC using ROC curve analysis and multivariate analysis adjusted for patient age. Main results and the role of chance The mean KIDSCORE™D5 of day–5 and day–6 blastocysts was 7.1±1.7 and 3.7±1.5, respectively. KIDSCORE™D5 of day–6 blastocysts was significantly lower than that of day–5 blastocysts (p Limitations, reasons for caution This study had a small sample size, and it was a retrospective single-center study. In addition, the relationship between KIDSCORE™D5 and clinical pregnancy rates may vary among facilities. Therefore, a prospective multicenter validation is necessary. Wider implications of the findings: Our study results indicated that KIDSCORE™D5 predicted clinical pregnancy and that morphokinetic parameters related to clinical pregnancy were similar between day–5 and day–6 blastocysts. Hence, morphokinetic evaluation can serve as a criterion for deciding which of multiple day–6 blastocysts can be transferred. Trial registration number Not applicable

Kapuas River in West Kalimantan with over 1,143 km is the largest river in Indonesia. It serves as a main refuge for high potential biodiversity. Oxbow lakes along the Kapuas River are of high ecological essential due to the number and the diversity of habitats they provide. In addition, oxbow lakes are critical components of the floodplain systems of lowland rivers. The objective of this study was to explore the diversity of oxbow lakes and their connectivity to the main river. We conducted fieldwork to measure water quality and ecological components at 12 oxbow lakes along the Kapuas River and two lakes in the Sentarum complex in January - February 2020. We measured the environmental parameters including water depth, water temperature, Secchi/transparency, pH, dissolved oxygen concentration, chlorophyll-a concentration, total nitrogen, and total phosphorus concentrations. Aquatic biota, including phytoplankton and zooplankton community structures, were also observed at 12 oxbow lakes along the Kapuas River and two lakes in the Sentraum complex. The sampling points represented both permanent and non-permanent connectivity of the oxbow lakes to the main river. The result indicates the variability of environmental characteristics between the lakes, based on water quality and biota analysis; for example, water acidity, as indicated by pH, was likely to seem like the main variable determining the oxbow lake biota. Also, the habitat connectivity of oxbow lakes to the main river has significantly influenced the biotic composition.

This paper presents the implementation of the physicomimetics framework in governing the behavior of a swarm of quadrotors. Each quadrotor uses only local information about itself and the neighboring quadrotors to determine its own movement by applying the principles of physicomimetics. Through these localized and relatively simple interactions, the swarm of quadrotors was able to organize itself into various structures and exhibit different swarm behaviors such as aggregation, obstacle avoidance, lattice formation, and dispersion.

Background: EMT is thought to contribute to metastasis in patients with breast cancer, leading to their poor prognosis. Pivotal phase III trials have demonstrated that eribulin improved overall survival in patients with triple negative metastatic breast cancer (MBC). Preclinical studies have shown that eribulin suppressed EMT and this phenomenon could be one of reason for an improved prognosis of MBC patients treated with eribulin. However, there is no direct clinical data on the effect of eribulin treatment on EMT in tumors of MBC patients. We designed a prospective study to clarify if eribulin treatment suppresses EMT in tumors of MBC patients. Patients and methods: Patients with recurrent or MBC were treated with eribulin (1.4 mg/m2 intravenously on days 1 and 8 of a 21-day cycle). Dose reductions were allowed according to eribulin's prescribing information. Treatment continued until disease progress, unacceptable toxic effects, or discontinuation requests from patients or physicians. Breast cancer tissue samples were obtained from all patients before and on day 15±4 of 1st cycle of eribulin treatment. The quantitative analysis of mRNA levels of EMT markers (E-cadherin, cytokelatin18, cytokelatin19, N-cadherin, vimentin, ZEB1, Slug, Snail, and Twist) were carried out by qPCR. Primary outcome measure was to assess the change from baseline to day 15±4 in mRNA levels of EMT related markers in tumor tissue. This study was approved by the Ethic Committee of Fujita Health University. Results: Eleven patients were enrolled. Median age of the patients was 63 years old (44-72). Of the 11 tumors, 6 were luminal B and 5 were triple negative (TN). Median number of prior chemotherapy regimen for recurrent or metastatic disease was 0 (0-3). Four patients were treated with dose reduced eribulin (1.1 mg/m2) and administration of eribulin on day 8 during 1st cycle of the treatment were skipped in 2 patients. To identify meaningful EMT markers, differences in expression levels of each EMT marker were investigated between TN and luminal B tumors. At baseline mRNA levels of N-cadherin and vimentin were higher in TN tumors than in luminal B tumors, 8.12±10.78 vs 1.02±0.68, 5.13±4.50 vs 0.88±0.47, respectively. After the treatment, a decrease of expression of N-cadherin and vimentin was more frequent in TN tumors (100% and 80%, respectively) than in luminal B tumors (33.3% and 16.7%, respectively). Frequency of a decrease of expression of ZEB1, Slug, Snail, and Twist in TN tumors and luminal B tumors were 80% (TN) vs 83.3% (luminal B), 80% vs 16.7%, 40% vs 66.7%, and 100% vs 50%, respectively. Conclusions: This is the first prospective study to investigate the effect of eribulin treatment on expression of EMT markers in tumors of MBC patients. We demonstrated that eribulin treatment suppressed EMT in tumors. Our results suggested that eribulin showed antitumor effect by improving the tumor microenvironment. In our study, eribulin seems to have different effects on EMT pathway in individual cases. Our findings may provide a light to a scientific basis for solving underlying mechanisms for improvement of overall survival of patients with MBC treated with eribulin. Citation Format: Utsumi T, Hayashi T, Kobayashi N, Hikichi M, Ushimado K, Ri Y, Nakano S, Fujii K, Ando T. Eribulin mesylate (eribulin) showed inhibitory effects on epithelial-mesenchymal transition (EMT) in tumors of metastatic breast cancer patients. -First preliminary report of a prospective study- [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-15-10.

To ensure the reliability of multi-stage centrifugal pumps, the prediction of axial thrust is an important issue for the design of balancing device and selection of thrust bearing. However, it is known that the fluid forces acting on rotor could be sensitively affected by the geometrical relations between rotor and stator especially at the low flow rate. Among them, the effect of axial offset of rotor has not been studied sufficiently though the axial offset is easily caused by accumulation of manufacturing tolerances and assembling errors. In this study, experimental/numerical investigations on the effect of axial rotor offset in a final stage model of a three-stage centrifugal pump are carried out. The axial offset is intentionally given to shaft system to the both of discharge/suction side. As a result, the axial thrust is significantly affected by the axial offset in the flow rate range below 50% of the design. It is shown by CFD analysis that this effect of axial offset is caused by the interaction between the back flow from the diffuser and the main flow.

We have carried out a powder X-ray diffraction investigation on antiferromagnetic Kondo semiconductorsCeRu2Al10 and CeOs2Al10 at low temperatures and under high pressures as well as the structural investigationon single crystal of these compounds. The results of powder X-ray studies of CeRu2Al10 and CeOs2Al10 indicatethat these compounds do not have structural transition at its antiferromagnetic ordering temperature. The resultsof single crystal structural refinement indicate that the b-axis of this crystal structure is insensitive not only topressure but also to temperature and that the effect of cooling to Ce–Ce distance for CeRu2Al10 is the same asthat for CeOs2Al10.

The Dst index has a long-term variation that is not associated with magnetic storms. We estimated the long-term non-storm component of the Dst variation by removing the short-term variation related to magnetic storms. The results indicate that the variation of the non-storm component includes not only a seasonal variation but also an irregular variation. The irregular long-term variation is likely to be due to an anti-correlation with the long-term variation of solar-wind activity. In particular, a clear anti-correlation is observed between the non-storm component of Dst and the long-term variation of the solar-wind dynamic pressure. This means that in the long term, the Dst index tends to increase when the solar-wind dynamic pressure decreases. We interpret this anti-correlation as an indication that the long-term non-storm variation of Dst is influenced by the tail current variation. The long-term variation of the solar-wind dynamic pressure controls the plasma sheet thermal pressure, and the change of the plasma sheet thermal pressure would cause the non-storm tail current variation, resulting in the non-storm variation of Dst.

Because of unique plasmonic features, nanostructured graphene such as graphene nanoribbons (GNRs) and quantum dots (GQDs) is attracting much interests. In this work, we investigated real-space characterization of surface plasmon polariton (SPP) in GQDs on SiC substrate by utilizing a scattering-type scanning near-field optical microscope (s-SNOM) in the mid-infrared (MIR) band. Nanoscale near-field images revealed that the SPP in the GQDs was excited at the wavenumber of 929.02 cm−1, where the SPP in two-dimensional (2D) graphene has not been reported. The present findings provide not only a deeper understanding of the SPP in graphene nanostructures, but also a first step for exploring new plasmonic functionalities impossible with conventional 2D graphene.

IAU Commission 6 “Astronomical Telegrams” had a single business meeting during Honolulu General Assembly of the IAU. It took place on Tuesday, 11 August 2015. The meeting was attended by Hitoshi Yamaoka (President), Daniel Green (Director of the Central Bureau for Astronomical Telegrams, CBAT, via Skype), Steven Chesley (JPL), Paul Chodas (JPL), Alan Gilmore (Canterbury University), Shinjiro Kouzuma (Chukyo University), Paolo Mazzali (Co-Chair of the Supernova Working Group), Elena Pian (Scuola Normale Superiore di Pisa), Marion Schmitz (chair IAU Working Group Designations + NED), David Tholen (University of Hawaii), Jana Ticha (Klet Observatory), Milos Tichy (Klet Observatory), Giovanni Valsecchi (INAF\slash Italy), Gareth Williams (Minor Planet Center). Apologies: Nikolai Samus (General Catalogue of Variable Stars, GCVS).

Unmanned aerial vehicle that is moving from one place to another needs to have a real-time obstacle avoidance controller to prevent collisions in the obstacles around it. In this paper, the concept of artificial potential field is proposed to implement obstacle avoidance in swarm of quadrotors. This is based on the assumptions that the target and obstacle will introduce a certain force that will direct the robot to its destination. The effectiveness of this method was tested in a computer simulation and verified using real quadrotors.

In this study, the possibility of using π-conjugated organic semiconducting polymers as real-time radiation detectors was explored. Polyaniline (PAni) was used to fabricate radiation sensors because of its relative long-term stability in air. Each fabricated sensor was then subjected to irradiation by α- and β-particles, and the real-time response was measured. The multichannel analyzer (MCA) data of the response signal for each irradiation was acquired and the detection efficiency, relative to the electrode bias voltage of the detector, was extracted.

Stereotactic body radiotherapy (SBRT) is a treatment option for patients with early stage lung cancer. Treatment duration can be >30 minutes per fraction with non-coplanar 3D-conformal radiotherapy (3D-CRT). Whilst this is generally well tolerated, faster delivery techniques are desirable. Volumetric modulated arc therapy (VMAT) allows for fast delivery of radiation treatment. The purpose of this planning study was to compare SBRT with 3D-CRT and VMAT, with VMAT plans generated using both single arc and 3 non-coplanar partial arcs. Ten patients who previously underwent SBRT (48 Gy in 4 fractions) with 3D-CRT were selected. VMAT plans were generated to treat the PTV while limiting doses to organs at risk. Cumulative dose volume histogram (DVH) parameters were compared between the 3 techniques using the Wilcoxon matched pairs test. Treatment delivery time was also assessed. Both VMAT techniques covered target volumes more conformally than 3D-CRT with a mean V48/VPTV of 1.21 for 3D-CRT, 1.03 for 3 arc plans and 1.01 for single arc plans (ρ = 0.005). Dose constraints to organs at risk were met using all three techniques. Mean lung doses were 2.93 Gy for 3D-CRT, 2.87 Gy for single arc and 2.73 Gy for the 3 arc technique (3-arc vs. 3D-CRT: ρ = 0.009). Lung V20 for 3D-CRT, 1 arc and 3 arcs were 3.24%, 2.89% and 2.73%, respectively (3-arc vs. 3D-CRT: ρ = 0.028). Mean time to deliver a single fraction was 13 minutes for 3D-CRT, 9.2 minutes for 3 arcs and 5.5 minutes for 1 arc. VMAT resulted in improved conformality compared to 3D-CRT. The 3 arc technique appears to have the lowest dose to lung although the magnitude is unlikely to be clinically significant. The main advantage of VMAT over 3D-CRT is faster treatment delivery time. Shortened treatment times are anticipated to improve tolerability of this treatment and reduce the chance of error due to intra-fraction motion.

The friction and wear properties of Si3N4–8mass% Al2O3–6mass% Y2O3, AISI H13 steel, AISI 52100 steel, Inconel 600, ZrO2–3 mol% Y2O3, WC-6mass% Co and BN-50mass% Ni disk specimens sliding against aluminum alloy 5052 were examined at 823 K in air. The AISI H13 steel, AISI 52100 steel and BN–50mass% Ni disk specimens exhibited relatively stable friction coefficients as low as 0.4–0.5, although the AISI 52100 steel and BN-50mass% Ni disk specimens exhibited the largest volume increase and the highest specific wear rates, respectively. On the other hand, the AISI H13 steel, ZrO2–3 mol% Y2O3 and WC-6mass% Co disk specimens exhibited much smaller volume changes than AISI 52100 steel, Inconel 600 and BN-50mass% Ni disk specimens. However, the ZrO2–3 mol% Y2O3 and WC-6mass% Co disk specimens exhibited unstable friction coefficients and the friction coefficients as high as 0.6, respectively. SEM-EDS analyses revealed large amount of Al and oxygen on the worn surfaces of the Si3N4–8mass% Al2O3–6mass% Y2O3, AISI H13 steel, AISI 52100 steel and ZrO2–3 mol% Y2O3 disk specimens, while much smaller amount of Al and oxygen were observed on the worn surfaces of the Inconel 600, WC-6mass% Co and BN-50mass% Ni disk specimens. In addition, distinct oxygen peaks were observed on the worn surfaces of all the aluminum alloy pin specimens, but such oxygen peaks were hardly observed on the non-worn surfaces of all the pin specimens.

Many minimally invasive surgical procedures are now performed using teleoperated robotic systems. However, such commercially available systems do not provide significant force feedback to the surgeon. This reduces surgeon's dexterity and increases tissue trauma when performing the operation. In this paper, a compact and lightweight forceps' manipulator using pneumatic artificial muscles (PAMs) for minimally invasive surgery is presented, which allows for the perception of manipulation force without the usage of the force sensor. The main advantage of this concept is that no force sensor has to be integrated into surgical instruments and inserted into the patient's body. Rather, a disturbance observer is integrated into the slave-side controller for the estimation of the external force acting at the forcep's tip. This approach reduces costs and stabilizability demands for forceps' manipulator while enables haptic feedback to the surgeons. Results of force perception experiments and comparison with forceps' manipulator driven by pneumatic cylinders are presented to validate the concepts.

Swarm robotics is one of the novel approaches being explored in multiple quadrotor. It aims to mimic social behaviors of animals and insects. This paper presents the physical implementation of the swarm behavior aggregation in a quadrotor swarm. It is implemented over a quadrotor swarm testbed that makes use of external motion capture cameras. The completed algorithm makes use of the artificial potential function model with a linear attraction and bounded repulsion. Results show successful demonstration of the aggregation algorithm with minimal error in position. It is tested for an increasing number of quadrotors and errors are seen to increase with swarm size. Results show an error of 3.293 cm from the individual target position for aggregation. It also shows and average aggregation speed of 1.896 secs for all test while having an increase in aggregation speed of about 1.772 sec per increase in swarm size. The time in aggregate is seen to be at an average of 98.5405% of the time. All the tests show successful demonstration of the swarming behavior which can now mark the start of development of implementation of more complex swarming behaviors.