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https://www.readbyqxmd.com/read/28340385/experimental-study-of-polyethylene-pyrolysis-and-combustion-over-hzsm-5-husy-and-mcm-41
#1
Que Huang, Changcheng Liu, Ruichao Wei, Jian Wang
The effects of temperatures, catalysts, and catalyst contents on polyethylene (PE) pyrolysis were investigated by using single-photon ionization time-of-flight mass spectrometry (SPI-TOFMS). The mass spectra of pyrolyzed PE and PE/catalysts from 300°C to 800°C illustrate that the pyrolysis reactions were apparently promoted and varied by introducing HZSM-5, HUSY, and MCM-41. As microporous catalysts, HZSM-5 and HUSY were found to accelerate the BTX formation at 400°C, which could not be observed for pure PE until 800°C...
March 14, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28340296/ultra-low-surface-recombination-velocity-in-passivated-ingaas-inp-nanopillars
#2
Aura Higuera-Rodriguez, Bruno Romeira, Simone Birindelli, Lachlan E Black, Barry Smalbrugge, Peter J van Veldhoven, Wilhelmus Erwin M M Kessels, Meint K Smit, Andrea Fiore
The III-V semiconductor InGaAs is a key material for photonics since it provides optical emission and absorption in the 1.55 μm telecommunication wavelength window. However, InGaAs suffers from pronounced non-radiative effects associated with its surface states, which affect the performance of nanophotonic devices for optical interconnects, namely nanolasers and nanodetectors. This work reports the strong suppression of surface recombination of undoped InGaAs/InP nanostructured semiconductor pillars using a combination of ammonium sulfide, (NH4)2S, passivation and silicon oxide, SiOx, coating...
March 24, 2017: Nano Letters
https://www.readbyqxmd.com/read/28339240/single-photon-thermal-ionization-of-c_-60
#3
Klavs Hansen, Robert Richter, Michele Alagia, Stefano Stranges, Luca Schio, Peter Salén, Vasyl Yatsyna, Raimund Feifel, Vitali Zhaunerchyk
We report on experiments which show that C_{60} can ionize in an indirect, quasithermal boiloff process after absorption of a single photon. The process involves a large number of incoherently excited valence electrons and yields electron spectra with a Boltzmann distribution with temperatures exceeding 10^{4}  K. It is expected to be present for other molecules and clusters with a comparatively large number of valence electrons. The astrophysical consequences are briefly discussed.
March 10, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28338814/korean-pediatric-and-adult-head-computational-phantoms-and-application-to-photon-specific-absorbed-fractions-calculations
#4
Daphnée Villoing, Dayton McMillan, Kwang Pyo Kim, Il Park, Ae-Kyoung Lee, Hyung-do Choi, Choonsik Lee
In recent decades, applications of single photon emission computed tomography and positron emission tomography in clinical neuroimaging have markedly increased. In this study, we developed a series of Korean computational head phantoms with detailed cranial substructures for 6-, 9-, 12- and 15-year-old children and adult by non-uniformly adjusting a template head phantom to match the Korean standard head dimensions. The Korean head phantoms were coupled with a Monte Carlo transport code to calculate age-dependent specific absorbed fraction (SAF) for the combination of 10 source and target regions and mono-energetic photons ranging from 0...
February 23, 2017: Radiation Protection Dosimetry
https://www.readbyqxmd.com/read/28338640/metal-based-psma-radioligands
#5
REVIEW
Eleni Gourni, Gjermund Henriksen
Prostate cancer is one of the most common malignancies for which great progress has been made in identifying appropriate molecular targets that would enable efficient in vivo targeting for imaging and therapy. The type II integral membrane protein, prostate specific membrane antigen (PSMA) is overexpressed on prostate cancer cells in proportion to the stage and grade of the tumor progression, especially in androgen-independent, advanced and metastatic disease, rendering it a promising diagnostic and/or therapeutic target...
March 24, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28337725/comparison-of-diagnostic-performance-of-four-software-packages-for-phase-dyssynchrony-analysis-in-gated-myocardial-perfusion-spect
#6
Koichi Okuda, Kenichi Nakajima, Shinro Matsuo, Soichiro Kashiwaya, Hiroto Yoneyama, Takayuki Shibutani, Masahisa Onoguchi, Mitsumasa Hashimoto, Seigo Kinuya
BACKGROUND: Phase analysis of gated myocardial perfusion single-photon emission computed tomography (SPECT) for assessment of left ventricular (LV) dyssynchrony was investigated using the following dedicated software packages: Corridor4DM (4DM), cardioREPO (cREPO), Emory Cardiac Toolbox (ECTb), and quantitative gated SPECT (QGS). The purpose of this study was to evaluate the normal values of 95% histogram bandwidth, phase standard deviation (SD), and entropy and to compare the diagnostic performance of the four software packages...
December 2017: EJNMMI Research
https://www.readbyqxmd.com/read/28337724/i-123-iomazenil-single-photon-emission-computed-tomography-for-detecting-loss-of-neuronal-integrity-in-patients-with-traumatic-brain-injury
#7
Kagari Abiko, Katsunori Ikoma, Tohru Shiga, Chietsugu Katoh, Kenji Hirata, Yuji Kuge, Kentaro Kobayashi, Nagara Tamaki
BACKGROUND: Traumatic brain injury (TBI) causes brain dysfunction in many patients. Using C-11 flumazenil (FMZ) positron emission tomography (PET), we have detected and reported the loss of neuronal integrity, leading to brain dysfunction in TBI patients. Similarly to FMZ PET, I-123 iomazenil (IMZ) single photon emission computed tomography (SPECT) is widely used to determine the distribution of the benzodiazepine receptor (BZR) in the brain cortex. The purpose of this study is to examine whether IMZ SPECT is as useful as FMZ PET for evaluating the loss of neuronal integrity in TBI patients...
December 2017: EJNMMI Research
https://www.readbyqxmd.com/read/28336741/differences-between-determinants-of-in-hospital-mortality-and-hospitalisation-costs-for-patients-with-acute-heart-failure-a-nationwide-observational-study-from-japan
#8
Noriko Sasaki, Susumu Kunisawa, Hiroshi Ikai, Yuichi Imanaka
OBJECTIVES: Although current case-mix classifications in prospective payment systems were developed to estimate patient resource usage, whether these classifications reflect clinical outcomes remains unknown. The efficient management of acute heart failure (AHF) with high mortality is becoming more important in many countries as its prevalence and associated costs are rapidly increasing. Here, we investigate the determinants of in-hospital mortality and hospitalisation costs to clarify the impact of severity factors on these outcomes in patients with AHF, and examine the level of agreement between the predicted values of mortality and costs...
March 22, 2017: BMJ Open
https://www.readbyqxmd.com/read/28335193/facile-synthesis-of-gd-functionalized-gold-nanoclusters-as-potential-mri-ct-contrast-agents
#9
Wenjun Le, Shaobin Cui, Xin Chen, Huanhuan Zhu, Bingdi Chen, Zheng Cui
Multi-modal imaging plays a key role in the earlier detection of disease. In this work, a facile bioinspired method was developed to synthesize Gd-functionalized gold nanoclusters (Gd-Au NCs). The Gd-Au NCs exhibit a uniform size, with an average size of 5.6 nm in dynamic light scattering (DLS), which is a bit bigger than gold clusters (3.74 nm, DLS), while the fluorescent properties of Gd-Au NCs are almost the same as that of Au NCs. Moreover, the Gd-Au NCs exhibit a high longitudinal relaxivity value (r1) of 22...
April 9, 2016: Nanomaterials
https://www.readbyqxmd.com/read/28333040/rigid-motion-correction-of-dual-opposed-planar-projections-in-single-photon-imaging
#10
Georgios I Angelis, William Ryder, John Gillam, Frederic Boisson, Andre Kyme, Roger Fulton, Steven Meikle, Peter Kench
Awake and/or freely moving small animal single photon emission imaging allows the continuous study of molecules exhibiting slow kinetics without the need to restrain or anaesthetise the animals. Estimating motion free projections in freely moving small animal planar imaging can be considered as a limited angle tomography problem, except that we wish to estimate the 2D planar projections rather than the 3D volume, where the angular sampling in all three axes depends on the rotational motion of the animal. In this study, we hypothesise that the motion corrected planar projections estimated by reconstructing an estimate of the 3D volume using an iterative motion compensating reconstruction algorithm and integrating it along the projection path, will closely match the true, motion-less, planar distribution regardless of the object motion...
March 23, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28333011/utility-of-deep-inspiration-breath-hold-for-left-sided-breast-radiation-therapy-in-preventing-early-cardiac-perfusion-defects-a-prospective-study
#11
Timothy M Zagar, Orit Kaidar-Person, Xiaoli Tang, Ellen E Jones, Jason Matney, Shiva K Das, Rebecca L Green, Arif Sheikh, Amir H Khandani, William H McCartney, Jorge Daniel Oldan, Terence Z Wong, Lawrence B Marks
PURPOSE: To evaluate early cardiac single photon computed tomography (SPECT) findings after left breast/chest wall postoperative radiation therapy (RT) in the setting of deep inspiration breath hold (DIBH). METHODS AND MATERIALS: We performed a prospective single-institution single-arm study of patients who were planned for tangential RT with DIBH to the left breast/chest wall (± internal mammary nodes). The DIBH was done by use of a controlled surface monitoring technique (AlignRT, Vision RT Ltd, London, UK)...
April 1, 2017: International Journal of Radiation Oncology, Biology, Physics
https://www.readbyqxmd.com/read/28332488/parkinson-disease
#12
REVIEW
Werner Poewe, Klaus Seppi, Caroline M Tanner, Glenda M Halliday, Patrik Brundin, Jens Volkmann, Anette-Eleonore Schrag, Anthony E Lang
Parkinson disease is the second-most common neurodegenerative disorder that affects 2-3% of the population ≥65 years of age. Neuronal loss in the substantia nigra, which causes striatal dopamine deficiency, and intracellular inclusions containing aggregates of α-synuclein are the neuropathological hallmarks of Parkinson disease. Multiple other cell types throughout the central and peripheral autonomic nervous system are also involved, probably from early disease onwards. Although clinical diagnosis relies on the presence of bradykinesia and other cardinal motor features, Parkinson disease is associated with many non-motor symptoms that add to overall disability...
March 23, 2017: Nature Reviews. Disease Primers
https://www.readbyqxmd.com/read/28331948/erratum-to-diagnostic-imaging-of-dementia-with-lewy-bodies-by-susceptibility-weighted-imaging-of-nigrosomes-versus-striatal-dopamine-transporter-single-photon-emission-computed-tomography-a-retrospective-observational-study
#13
Koji Kamagata, Tomoya Nakatsuka, Ryuji Sakakibara, Yohei Tsuyusaki, Tomohiro Takamura, Kanako Sato, Michimasa Suzuki, Masaaki Hori, Kanako K Kumamaru, Tsutomu Inaoka, Shigeki Aoki, Hitoshi Terada
No abstract text is available yet for this article.
March 22, 2017: Neuroradiology
https://www.readbyqxmd.com/read/28331022/effect-of-non-pharmacological-intervention-for-apathy-response-to-one-on-one-reminiscence-based-intervention
#14
Akira Okada, Tetsuya Ueda
Apathy has adverse consequences for patients and caregivers. However, the therapeutic approach remains uncertain. Here, we present the case of a man aged 67 years who only developed apathy after surgery for oesophageal cancer. He showed no response to intervention with donepezil, a 'brain training' video game and psychoeducation for apathy. Subsequently, we implemented a programme designed to facilitate recall of 2 themes (editorial content and television shows during the week) once a week. After 3 months, the scores of 2 apathy scales rated by the patient's wife, psychological test scores and brain perfusion single-photon emission CT data improved compared with those obtained before intervention...
March 22, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/28330661/association-between-high-sensitivity-cardiac-troponin-levels-and-myocardial-ischemia-during-mental-stress-and-conventional-stress
#15
Muhammad Hammadah, Ibhar Al Mheid, Kobina Wilmot, Ronnie Ramadan, Ayman Alkhoder, Malik Obideen, Naser Abdelhadi, Shuyang Fang, Ijeoma Ibeanu, Pratik Pimple, Heval Mohamed Kelli, Amit J Shah, Brad Pearce, Yan Sun, Ernest V Garcia, Michael Kutner, Qi Long, Laura Ward, J Douglas Bremner, Fabio Esteves, Paolo Raggi, David Sheps, Viola Vaccarino, Arshed A Quyyumi
OBJECTIVES: This study sought to investigate whether patients with mental stress-induced myocardial ischemia will have high resting and post-mental stress high-sensitivity cardiac troponin I (hs-cTnI). BACKGROUND: Hs-cTnI is a marker of myocardial necrosis, and its elevated levels are associated with adverse outcomes. Hs-cTnI levels may increase with exercise in patients with coronary artery disease. Mental stress-induced myocardial ischemia is also linked to adverse outcomes...
March 10, 2017: JACC. Cardiovascular Imaging
https://www.readbyqxmd.com/read/28329376/comparison-of-the-prognostic-value-of-negative-non-invasive-cardiac-investigations-in-patients-with-suspected-or-known-coronary-artery-disease-a-meta-analysis
#16
Martijn W Smulders, Caroline Jaarsma, Patricia J Nelemans, Sebastiaan C A M Bekkers, Jan Bucerius, Tim Leiner, Harry J G M Crijns, Joachim E Wildberger, Simon Schalla
Aims: To compare the prognostic value of negative non-invasive cardiac investigations (coronary computed tomographic angiography [CCTA], cardiovascular magnetic resonance [CMR], exercise electrocardiographic testing [EET], positron emission tomography [PET], stress-echocardiography [SE], and single-photon emission tomography [SPECT]) in patients with suspected or known coronary artery disease (CAD) and to explore the effect of adjustment for population event risk and presence of CAD. Methods and results: MEDLINE/PubMed database, EMBASE and Cochrane Library were searched from January-1990 to April-2015 for studies reporting annual event rates (AER) of myocardial infarction (MI) and cardiac death...
February 27, 2017: European Heart Journal Cardiovascular Imaging
https://www.readbyqxmd.com/read/28327190/primary-pain-generator-identification-by-ct-spect-in-a-patient-with-low-back-pain-a-case-report
#17
Gabriel Tender, Adriana Constantinescu, Andrew Conger, Anthony DiGiorgio
BACKGROUND: Chronic low back pain is one of the most common conditions encountered in the middle-age population. Identifying the primary pain generator is notoriously difficult. The computed tomography-single-photon emission computed tomography (CT-SPECT) is emerging as a new diagnostic modality for this purpose. CASE PRESENTATION: This 68-year-old Caucasian male presented with intractable low back pain refractory to maximal conservative treatment, including medication and extensive physical therapy...
March 21, 2017: BMC Research Notes
https://www.readbyqxmd.com/read/28320195/combined-use-of-dopamine-transporter-imaging-dat-spect-and-123-i-metaiodobenzylguanidine-mibg-myocardial-scintigraphy-for-diagnosing-parkinson-s-disease
#18
Fumihito Yoshii, Masafuchi Ryo, Yasuhiko Baba, Takashi Koide, Jun Hashimoto
BACKGROUND: To examine whether combined use of (123)I-FP-CIT dopamine transporter single photon emission computed tomography (DAT-SPECT) and (123)I-MIBG myocardial scintigraphy (MIBG) is superior to either modality alone for diagnosing Parkinson's disease (PD). METHODS: Patients with probable PD (n=120) who underwent both DAT-SPECT and MIBG myocardial scintigraphy within short intervals were enrolled. Specific binding ratio (SBR) of DAT-SPECT images and heart-to-mediastinum (H/M) ratio of MIBG images were used as quantitative measures...
April 15, 2017: Journal of the Neurological Sciences
https://www.readbyqxmd.com/read/28317908/determination-of-low-loss-in-isotopically-pure-single-crystal-28-si-at-low-temperatures-and-single-microwave-photon-energy
#19
Nikita Kostylev, Maxim Goryachev, Andrey D Bulanov, Vladimir A Gavva, Michael E Tobar
The low dielectric losses of an isotopically pure single crystal (28)Si sample were determined at a temperature of 20 mK and at powers equivalent to that of a single photon. Whispering Gallery Mode (WGM) analysis revealed large Quality Factors of order 2 × 10(6) (dielectric loss ~5 × 10(-7)) at high powers, degrading to 7 × 10(-5) (dielectric loss ~1.4 × 10(-6) at single photon energy. A very low-loss narrow line width paramagnetic spin flip transition was detected with extreme sensitivity in (28)Si, with very small concentration below 10(10) cm(-3) (less than 10 parts per trillion) and g-factor of 1...
March 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28317651/clinical-validity-of-presynaptic-dopaminergic-imaging-with%C3%A2-123-i-ioflupane%C3%A2-and-noradrenergic-imaging-with-123-i-mibg-in-the-differential-diagnosis-between-alzheimer-s-disease-and-dementia-with-lewy-bodies-in-the-context-of-a-structured-5-phase-development
#20
REVIEW
Ida Sonni, Osman Ratib, Marina Boccardi, Agnese Picco, Karl Herholz, Flavio Nobili, Andrea Varrone
The use of biomarkers (BMs) for accurate diagnosis of Alzheimer's disease (AD) has been proposed by recent diagnostic criteria; however, their maturity is not sufficient to grant implementation in the clinical routine. A proper diagnostic process requires not only confirmation of the disease but also the exclusion of similar disorders entering differential diagnosis, like dementia with Lewy bodies (DLB). This review is aimed at evaluating the clinical validity of (123)I-ioflupane brain single photon emission tomography and (123)I-MIBG cardiac scintigraphy as imaging BMs for DLB...
April 2017: Neurobiology of Aging
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