Future tracking detectors have to be both space and time measuring devices at the single pixel level. This is strongly motivated by the extremely high interaction intensities foreseen at collider ...experiments of the next couple of decades and possibly beyond. Presently, no satisfactory technical solutions are available and important development programs have started in this direction. Minimal system requirements are: the capability to sustain fluences greater than some 1016 1 MeV neutron equivalent/cm2 and radiation doses of some Grad; space resolutions around 10μm and time resolutions below 50 ps. 3D silicon sensors have already found application for their very high radiation hardness and have intrinsic characteristics which can be exploited for fast response. Recently, tests have been made by the TIMESPOT collaboration on 55μm pitch 3D-trench sensor prototypes, expressly designed for timing applications, which give important results in terms of time resolution. The tests have been performed both in the laboratory under a 1030 nm pulsed laser beam and under minimum ionizing particle beam. The tests yield values of time resolution below 30 ps. Such results indicate that, as of today, these devices are possibly the only ones capable to satisfy the complete set of system requirements for a vertex detector of the next generation and can be considered as a very interesting solution to be further developed and finalized. This paper will describe the characteristics of the developed sensors, the kind of measurements performed and will discuss the results obtained.
Cutaneous leishmaniasis (CL) is a chronic skin infection caused by Leishmania parasites, causing single or multiple skin nodules and ulcers on the exposed body locations. Healing of lesions is ...followed by scar formation. Active and healed CL lesions may affect patient's health related quality of life (HRQL). The aim of this study was to determine whether the body location of the leishmaniasis lesions affects the HRQL of localized CL patients in Suriname. The HRQL of 163 patients with CL was assessed by Skindex-29 and EQ-5D/VAS questionnaires. Forty-six patients out of the total study population also participated in a qualitative anthropological study involving in depth interviews. All patients were allocated in 4 groups in the following hierarchy: head and face, upper limbs, lower limbs and trunk. Patients with lesions on the lower limbs had significantly higher Skindex-29 scores, indicating worse HRQL, in the symptom scale compared to lesions on head/face and trunk. The lower limb group was more likely to report problems in the dimensions self-care, mobility, daily activities and pain/discomfort of the EQ-5D. Little to no social stigma was reported in the in-depth interviews. The findings of this study indicate that Surinamese patients with CL lesions located on the lower limbs had more impairment in HRQL than on other body locations. Stigma related to CL seems to be virtually absent in Suriname.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Video‐based flipped class instruction can strengthen the learning motivation of students. The effectiveness of flipped class instruction on teaching effectiveness and subject satisfaction has been ...evaluated previously. The present study aims to examine the impact of two aspects of subject reading motivation. A total of 100 secondary school students were recruited from 4 classes of 25 students (ie, video‐based flipped Mathematics class, traditional Mathematics class, video‐based flipped Liberal Studies (LS) class and traditional LS class) in two local secondary schools. The same teachers taught both the traditional and video‐based flipped classes in their subject. The students filled in questionnaires which measured: motivation for general reading; motivation for subject reading; academic subject satisfaction and perceived teaching effectiveness of the teachers. Analysis of covariance controlling for motivation for general reading revealed that students in the flipped classes reported significantly lower motivation for subject reading including reading curiosity, reading importance and reading compliance (t (1,98) = 10.52, p < 0.001; t (1,98) = 7.68, p < 0.001; t (1,98) = 20.39, p < 0.001, respectively). However, students in the flipped classes reported significantly higher satisfaction and teaching effectiveness than those in the traditional classes (t (1,98) = −15.61. p < 0.001; t (1,98) = −11.98, p <0.001, respectively). A partial correlation controlling for motivation for general reading indicated that motivation for subject reading was negatively associated with academic subject satisfaction and perceived teaching effectiveness of teachers (rs ranged from −0.51 to −0.62, p < 0.001). Video‐based flipped class instruction was not only related to increased academic subject satisfaction and teaching effectiveness but also associated with lower motivation for subject reading. These findings suggest that video‐based flipped class instruction had limited capability to strengthen the learning motivation of students.
Air ionizers and 222-nm krypton-chlorine (KrCl) excilamp have proven to be effective disinfection apparatus for bacteria and viruses with limited health risks. We determined inactivation efficiencies ...by operating them individually and in combined modules. Gram-positive and gram-negative bacteria, non-enveloped dsDNA virus, and enveloped dsRNA virus were examined in a designed air disinfection system. Our results showed that the bioaerosols were inactivated efficiently by negative ionizers and far-UVC (222-nm), either used individually or in combination. Among which the combined modules of negative ionizers and KrCl excilamp had the best disinfection performance for the bacteria. The aerosolized virus P22 and Phi 6 were more susceptible to 222-nm emitted by KrCl excilamp than negative air ions. Significant greater inactivation of bacterial bioaerosols were identified after treated by combined treatment of negative air ion and far-UVC for 2 minutes (Escherichia coli, 6.25 natural log (ln) reduction; Staphylococcus epidermidis, 3.66 ln reduction), as compared to the mean sum value of inactivation results by respective individual treatment of negative ionizers and KrCl excilamp (Escherichia coli, 4.34 ln; Staphylococcus epidermidis, 1.75 ln), indicating a synergistic inactivation effect. The findings provide important baseline data to support the design and development of safe and high-efficient disinfection systems.
Display omitted
•The bacteria and bacteriophage were effectively inactivated by far-UVC (222-nm) and negative air ions.•Synergistic effect on bacterial inactivation was observed when combining far-UVC and negative air ions.•The combined treatment of far-UVC and negative air ions could enhance efficiency by 37–116 %.•This air disinfection system produced a very low ozone concentration.
Skeletal muscle thickness is a valuable indicator of several aspects of a muscle's functional capabilities. We used computational analysis of ultrasound images, recorded from 10 humans walking and ...running at a range of speeds (0.7-5.0 m s
), to quantify interactions in thickness change between three ankle plantar flexor muscles (soleus, medial and lateral gastrocnemius) and quantify thickness changes at multiple muscle sites within each image. Statistical analysis of thickness change as a function of stride cycle (1d statistical parametric mapping) revealed significant differences between soleus and both gastrocnemii across the whole stride cycle as they bulged within the shared anatomical space. Within each muscle, changes in thickness differed between measurement sites but not locomotor condition. For some of the stride, thickness measures taken from the distal-mid image region represented the mean muscle thickness, which may therefore be a reliable region for these measures. Assumptions that muscle thickness is constant during a task, often made in musculoskeletal models, do not hold for the muscles and locomotor conditions studied here and researchers should not assume that a single thickness measure, from one point of the stride cycle or a static image, represents muscle thickness during dynamic movements.
Bioaerosols play a significant role in the transmission of many infectious diseases, especially in enclosed indoor environments. Ultraviolet (UV) disinfection has demonstrated a high efficacy in ...inactivating microorganisms suspended in the air. To develop more effective and efficient UV disinfection protocols, it is necessary to evaluate and optimize the effectiveness of UV disinfection against aerosolized bacteria and viruses across the entire UV spectrum. In this study, we evaluated the performance of UV disinfection across the UV spectrum, ranging from 222 to 365 nm, against aerosolized bacteria and viruses, including Escherichia coli, Staphylococcus epidermidis, Salmonella enterica, MS2, P22, and Phi6. Six commonly available UV sources, including gas discharge tubes and light-emitting diodes with different emission spectra, were utilized, and their performance in terms of inactivation efficacy, action spectrum, and energy efficiency was determined. Among these UV sources, the krypton chloride excilamp emitting at a peak wavelength of 222 nm was the most efficient in inactivating viral bioaerosols. A low-pressure mercury lamp emitting at 254 nm performed well on both inactivation efficacy and energy efficiency. A UV light-emitting diode emitting at 268 nm demonstrated the highest bacterial inactivation efficacy, but required approximately 10 times more energy to achieve an equivalent inactivation level compared with that of the krypton chloride excilamp and low-pressure mercury lamp. This study provides insights into UV inactivation on bioaerosols, which can guide the development of effective wavelength-targeted UV air disinfection technologies and may significantly help reduce bioaerosol transmission in public areas.
Abstract
BACKGROUND
The differentiation between intracranial atherosclerotic stenosis (ICAS) and intracranial embolism as the immediate cause of acute ischemic stroke requiring endovascular therapy ...is important but challenging. In cases of ICAS, we often observe a phenomenon we call the microcatheter “first-pass effect,” which is temporary blood flow through the occluded intracranial artery when the angiographic microcatheter is initially advanced through the site of total occlusion and immediately retrieved proximally.
OBJECTIVE
To evaluate whether this microcatheter first-pass effect can be used to differentiate ICAS from intracranial embolism.
METHODS
A total of 61 patients with acute ischemic stroke resulting from large intracranial artery occlusion and in whom recanalization was achieved by endovascular treatment were included in the study. The microcatheter first-pass effect was tested in these patients. The sensitivity, specificity, positive predictive values (PPV), and accuracy of the microcatheter first-pass effect for prediction of ICAS were assessed.
RESULTS
The microcatheter first-pass effect was more frequently observed in patients with ICAS than in those with intracranial embolism (90.9% vs 12.8%, P < .001). For identifying ICAS, sensitivity, specificity, PPV, and accuracy of the microcatheter first-pass effect were 90.9%, 87.2%, 80.0%, 88.5%, respectively.
CONCLUSION
The sensitivity and PPV of the microcatheter first-pass effect are high for prediction of ICAS in patients with acute symptoms.
The PANDA Strip ASIC: PASTA Lai, A.
Journal of instrumentation,
01/2018, Letnik:
13, Številka:
1
Journal Article
Recenzirano
PASTA is the 64 channel front-end chip, designed in a 110 nm CMOS technology to read out the strip sensors of the Micro Vertex Detector (MVD) of the PANDA experiment. This chip provides high ...resolution timestamp and deposited charge information by means of the time-over-threshold technique. Its working principle is based on a predecessor, the TOFPET ASIC, that was designed for medical applications. A general restructuring of the architecture was needed, in order to meet the specific requirements imposed by the physics programme of PANDA, especially in terms of radiation tolerance, spatial constraints, and readout in absence of a first level hardware trigger. The first revision of PASTA is currently under evaluation at the Forschungszentrum Jülich, where a data acquisition system dedicated to the MVD prototypes has been developed. This paper describes the main aspect of the chip design, gives an overview of the data acquisition system used for the verification, and shows the first results regarding the performance of PASTA.
Metal-assisted chemical etching (MACE) is a versatile anisotropic etch for silicon although its mechanism is not well understood. Here we propose that the Schottky junction formed between metal and ...silicon plays an essential role on the distribution of holes in silicon injected from hydrogen peroxide. The proposed mechanism can be used to explain the dependence of the etching kinetics on the doping level, doping type, crystallographic surface direction, and etchant solution composition. We used the doping dependence of the reaction to fabricate a novel etch stop for the reaction.
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