Porous Nitinol with a three-dimensional anisotropic interconnective open pore structure has been successfully produced by the combustion synthesis (CS) of elemental Ni and Ti powders. The resulting ...product can be tailored to closely match the stiffness of cancellous bone to minimize stress shielding. The average elastic modulus was approximately 1 GPa for a porosity of 60 vol% and the average pore size of 100-500 µm. The low elastic modulus meets the basic demand for orthopedic bone ingrowth applications. Furthermore, porous Nitinol was composed of cubic (austenitic) and monoclinic (martensitic) NiTi compounds without the presence of Ni metal or Ni-rich phases. The resulting product exhibits excellent corrosion resistance with breakdown potentials above 750mV. An ovine study in cortical sites of the tibia demonstrated rapid osseointegration into the porous strucutre as early as two weeks and complete bone growth across the implant at six weeks. A separate ovine study showed complete through-growth of bone at four months using a lumbar interbody fusion model, substantiating the use of porous Nitinol as an implant material for applications in the spine. Porous Nitinol is thus a promising biomaterial with proven biocompatibility and exceptional osseointegration performance which may enhance the healing process and promote long-term fixation, making it a strong candidate for a wide range of orthopedic implant applications.
Video capsule endoscopy has been established in diagnosis of small-bowel disease and has been evaluated for esophageal pathology and recently for colorectal diagnostics. Gastric capsule endoscopy has ...not hitherto been feasible due to the stomach's large surface area and volume. We present the first application of a magnetically navigated capsule in the human stomach.
29 volunteers and 24 patients (men 42, women 11; mean age 47.5 years) were included in a feasibility study. Low-level magnetic fields were used to maneuver the double-sensor video capsule within the human stomach with an air-water interface provided by ingestion of 1300 ml water within 1 hour before examination. Visualization of all parts of the stomach was attempted; time for visualization was recorded, and a subjective assessment of completeness of visualization was documented.
There was technical failure in one individual; thus technical success rate was 98 %. In the 52 remaining cases, examiners assessed that the antrum, body, fundus, and cardia were fully visualized in 98 %, 96 %, 73 % and 75 %, respectively. Mean duration of examinations was 30 minutes (range 8 - 50), with a longer time (mean 37 minutes) for volunteers for study reasons. In total, 30 findings were identified: 14 were detected by both gastroscopy and capsule, 10 lesions were identified by guided capsule examination only, 6 by gastroscopy only. No significant capsule-related adverse events occurred.
Magnetically navigated video capsule endoscopy appears to be feasible and sufficiently accurate for gastric examination. It may permit endoscopic examinations that are more patient-friendly and without sedation. Comparative studies are under way.
Michel parameters are kinematic values defined as bilinear combinations of the coupling terms in the general matrix element of the Fermi interaction where all possible Lorentz-invariant scalar, ...vector and tensor terms are included. The leptonic τ decays provide an excellent laboratory in which to measure the Michel parameters. Any deviation of these parameters from the Standard Model expectation would indicate New Physics. Two Michel parameters, η¯ and ξκ, can only be measured in the radiative leptonic decay. These parameters have previously been measured in the radiative decay of the muon but as yet have not been measured in τ decays. We report the results of a feasibility study of the measurement of η¯ and ξκ in radiative leptonic τ decays at Belle and Belle II.
Site-specific DNA recombination is important for basic cellular functions including viral integration, control of gene expression, production of genetic diversity and segregation of newly replicated ...chromosomes, and is used by bacteriophage lambda to integrate or excise its genome into and out of the host chromosome. lambda recombination is carried out by the bacteriophage-encoded integrase protein (lambda-int) together with accessory DNA sites and associated bending proteins that allow regulation in response to cell physiology. Here we report the crystal structures of lambda-int in higher-order complexes with substrates and regulatory DNAs representing different intermediates along the reaction pathway. The structures show how the simultaneous binding of two separate domains of lambda-int to DNA facilitates synapsis and can specify the order of DNA strand cleavage and exchange. An intertwined layer of amino-terminal domains bound to accessory (arm) DNAs shapes the recombination complex in a way that suggests how arm binding shifts the reaction equilibrium in favour of recombinant products.
A scintillation counter consisting of a pure CsI crystal and avalanche photodiodes (Hamamatsu APD S8664-55 and S8664-1010) has been studied for the upgrade of the end cap electromagnetic calorimeter ...of Belle II detector. An essential increase of the light output was achieved with wavelength shifters based on nanostructured organosilicon luminophores.
•A scintillation counter consisting of a pure CsI crystal and avalanche photodiodes has been studied.•The equivalent noise charge and equivalent noise energy of the counter have been measured.•An essential increase of the light output was achieved with wavelength shifters.
To identify the precise molecular processes to induce DNA lesions, we attempt a novel spectroscopy of X-ray induced luminescence (XIL) using soft X-ray synchrotron radiation, which is a ...non-destructive analysis of the reaction intermediates in the elementary reaction pathway of damage induction and self-organized restoration. Using a liquid micro-jet technique to introduce aqueous samples in a vacuum chamber, we measure UV-visible luminescence from nucleotide solution as a function of the soft X-ray energy from the nitrogen to oxygen K-edge region. The XIL intensities for the nucleotide solutions are significantly enhanced in the soft X-ray region (410-530 eV) which is ascribed to the K-shell excitation/ionization of nitrogen atoms in the nucleobases. Furthermore, the XIL spectra do not show any signature of X-ray absorption near-edge structure (XANES) of the nucleobases. This is because the luminescence intensities collected from the integral area of the micro-jet only reflect the quantum yield of luminescence of the absorbed X-ray into UV-visible light irrespective of the absorption cross sections, i.e. of XANES. Thus the present result is the first evidence of luminescence as a result of X-ray absorption of aqueous nucleotides.
Introduction: In our former study, we had validated the previously developed predictive model for in-hospital falls (Saga fall risk model) using eight simple factors (age, sex, emergency admission, ...department of admission, use of hypnotic medications, history of falls, independence of eating, and Bedriddenness ranks BRs), proving its high reliability. We found that only admission to the neurosurgery department, history of falls, and BRs had significant relationships with falls. In the present study, we aimed to clarify whether each of these three items had a significant relationship with falls in a different group of patients. Methods: This was a single-center based, retrospective study in an acute care hospital in a rural city of Japan. We enrolled all inpatients aged 20 years or older admitted from April 2015 to March 2018. We randomly selected patients to fulfill the required sample size. We performed multivariable logistic regression analysis using forced entry on the association between falls and each of the eight items in the Saga fall risk model 2. Results: A total of 2932 patients were randomly selected, of whom 95 (3.2%) fell. The median age was 79 years, and 49.9% were men. Multivariable analysis showed that female sex (odds ratio OR 0.6, 95% confidence interval CI 0.39-0.93, p = 0.022), having a history of falls (OR 1.9, 95% CI 1.16-2.99, p = 0.010), requiring help with eating (OR 1.9, 95% CI 1.12-3.35, p = 0.019), BR of A (OR 6.6, 95% CI 2.82-15.30, p < 0.001), BR of B (OR 7.5, 95% CI 2.95-19.06, p < 0.001), and BR of C (OR 4.1, 95% CI 1.53-11.04, p = 0.005 (were significantly associated with falls. Conclusion: History of falls and BRs were independently associated with in-hospital falls. Keywords: bedridden, Bedriddenness ranks, fall, predictive model, validation, Saga fall risk model 2
The educational effects of a hands-on clinical clerkship on medical students at the Department of General medicine of Japanese university hospitals remain to be clarified. This study aimed to ...determine how such education affects medical students' self-evaluation of their clinical skills.
We enrolled 5th-year-grade students at the Department of General Medicine, Saga University Hospital, Japan in 2017. The students were divided into those who were going to have Japanese traditional-style observation-based training mainly in the outpatient clinic (Group O) and those in the 2018, new-style, hands-on clinical clerkship as one of the group practice members in outpatient and inpatient clinics (Group H). A questionnaire survey using the 4-point Likert scale for self-evaluation of the students' clinical skills at the beginning and the end of their training was conducted in both groups. The pre- and post-training scores of each item in both groups were compared and analyzed using the Mann-Whitney test.
All 99 students in Group O and 121 of 123 students in Group H answered the questionnaires. The response rate was 99%. Two items regarding the abilities of "can perform a systemic physical examination quickly and efficiently" and "can clearly explain the current medical condition, therapeutic options, or risks associated with treatment, and discuss the process for obtaining informed consent" showed higher scores in the post-training survey in Group H than in Group O. There were no differences in these scores in the pre-training survey between the two groups.
A hands-on clinical clerkship at the Department of General medicine in a university hospital in Japan provided medical students with higher self-confidence in their skills of performing a physical examination and better understanding of patients' treatment options and the process of informed consent than observation-based training.
Background: It is unclear how much effort Japanese university general medicine (GM) departments, which teach basic medical skills and have a high affinity for clinical practice, devote to medical ...education, particularly undergraduate education. This study aimed to clarify the contribution of GM departments of Japanese universities to medical education. Patients and Methods: This was a questionnaire-based descriptive study of GM departments of Japanese universities. We sent the questionnaire created using Google Forms by email, and the universities responded by Internet. The department chairperson of the universities' main hospital was responsible for completing the questionnaire. It covered the number of staff, inpatients over the previous 3 years, affiliated hospitals, classroom lectures, and practical training sessions per year for each academic year in medical faculty and students accepted for clinical clerkship. Items also included the effort for clinical training, research, and education and the effort for undergraduate, initial clinical residency, and specialty program training. Results: In all, 46 of 71 universities responded, and we included 43 in our analysis. The median number of medical staff was 7; the median number of inpatients over the previous 3 years was 76. The median number of classroom lectures of the GM department was 1 for 1st-year, 5 for 3rd-year, 9 for 4th-year, and 0 for 2nd-, 5th-, and 6th-year students. The median total number of accepted students for clinical clerkship was 120. The median educational effort of the GM department was 30. With total educational effort set at 100, the median effort for undergraduate education was 45, for postgraduate residency 30, and for specialty program training 20. Conclusion: The undergraduate medical education by GM departments of Japanese universities was provided mainly in clinical settings for almost all medical students. A focus on exposing students to GM in early academic years would improve the educational environment. Keywords: clinical clerkship, general medicine, medical education, specialty program, university
PDF
