Oral History Interview: Verona A. Clarke

This interview is one of series conducted concerning Oral Histories of African-American women who taught in West Virginia public schools. Verona Clarke\u27s daughter Bobbi Jean Clarke participated in this interview. Verona A. Clarke began teaching at Genoa Elementary School in Genoa, West Virginia. She gives us detailed information about her family throughout the interview, including family life, a relative who was a slave, much information about her husband and medical organizations her husband belonged to (he was a dentist), as well as her daughter Bobbi Jean Clarke. Her childhood is another topic, and she discusses childhood social activities. Education is a large topic as well, and she discusses it in depth. She attended Liberty High School, Bluefield State College, and Ohio State University. She was also a part of the Delta sorority (Delta Sigma Theta?), and also tells the interviewers about her friends during school and after. She discusses her employment history, including work outside of teaching (such as a school cafeteria and a tobacco field). She taught home economics at the Appalachian Power Company (for the Department of Agriculture?) and also at Williamson High School, both of which she discusses. Race relations is another big topic, and she gives us information about segregation in businesses and schools, the desegregation of schools, Martin Luther King, Jr., and the Civil Rights Movement. Some other topics include: church and religion in her life; organizations she belonged to; her views on education in general; thoughts on her life in general; as well as other subjects. She ends with more information about her family.https://mds.marshall.edu/oral_history/1572/thumbnail.jp

The biology and treatment of acute long-bones diaphyseal fractures: Overview of the current options for bone healing enhancement

Diaphyseal fractures represent a complex biological entity that could often end into impaired bone-healing, with delayed union and non-union occurring up to 10% of cases. The role of the modern orthopaedic surgeon is to optimize the fracture healing environment, recognize and eliminate possible interfering factors, and choose the best suited surgical fixation technique. The impaired reparative process after surgical intervention can be modulated with different surgical techniques, such as dynamization or exchange nailing after failed intramedullary nailing. Moreover, the mechanical stability of a nail can be improved through augmentation plating, bone grafting or external fixation techniques with satisfactory results. According to the “diamond concept”, local therapies, such as osteoconductive scaffolds, bone growth factors, and osteogenic cells can be successfully applied in “polytherapy” for the enhancement of delayed union and non-union of long bones diaphyseal fractures. Moreover, systemic anti-osteoporosis anabolic drugs, such as teriparatide, have been proposed as off-label treatment for bone healing enhancement both in fresh complex shaft fractures and impaired unions, especially for fragility fractures. The article aims to review the biological and mechanical principles of failed reparative osteogenesis of diaphyseal fractures after surgical treatment. Moreover, the evidence about the modern non-surgical and pharmacological options for bone healing enhancement will discussed

Photo-physical properties of He-related color centers in diamond

Diamond is a promising platform for the development of technological applications in quantum optics and photonics. The quest for color centers with optimal photo-physical properties has led in recent years to the search for novel impurity-related defects in this material. Here, we report on a systematic investigation of the photo-physical properties of two He-related (HR) emission lines at 535 nm and 560 nm created in three different diamond substrates upon implantation with 1.3 MeV He+ ions and subsequent annealing. The spectral features of the HR centers were studied in an "optical grade" diamond substrate as a function of several physical parameters, namely the measurement temperature, the excitation wavelength and the intensity of external electric fields. The emission lifetimes of the 535 nm and 560 nm lines were also measured by means of time-gated photoluminescence measurements, yielding characteristic decay times of (29 +- 5) ns and (106 +- 10) ns, respectively. The Stark shifting of the HR centers under the application of an external electrical field was observed in a CVD diamond film equipped with buried graphitic electrodes, suggesting a lack of inversion symmetry in the defects' structure. Furthermore, the photoluminescence mapping under 405 nm excitation of a "detector grade" diamond sample implanted at a 1x1010 cm-2 He+ ion fluence enabled to identify the spectral features of both the HR emission lines from the same localized optical spots. The reported results provide a first insight towards the understanding of the structure of He-related defects in diamond and their possible utilization in practical applicationsComment: 9 pages, 3 figure

Complications and Intraoperative Fractures in Reverse Shoulder Arthroplasty: A Systematic Review

Introduction: The reverse shoulder arthroplasty is nowadays a treatment option for a variety of shoulder problems. As its incidence rose, also the number of complications increased, including intraoperative fractures. Significance: We performed a systematic review and critical analysis of the current literature following the PRISMA guidelines. Our purpose was to: 1) determine incidence, causes, and characteristics of intraoperative fractures; 2) evaluate their current treatment options, possible related complications, reoperation rates, and the patients’ outcome; and 3) determine the overall incidence of each complication related to reverse shoulder arthroplasty. The articles were selected from PubMed medical database in April 2020 using a comprehensive search strategy. Rayyan software was used to support the selection process of the records. A descriptive and critical analysis of the results was performed. Results: The study group included a total of 13,513 reverse shoulder arthroplasty procedures. The total number of complications was 1647 (rate 12.1%). The most common complication was dislocation (340 cases, rate 2.5%). Forty-six studies reported a total of 188 intraoperative fractures among the complications (rate 1.4%). The intraoperative fracture rate was 2.9% and 13.6% in primary and revision settings, respectively. There were 136 humeral fractures, 60% of them occurred in revision RSAs, during the removal of the previous implant, and involved the shaft in the majority of cases (39%). Glenoid fractures were 51 and occurred mostly during the reaming of the glenoid. We observed 7 further related complications (rate of 4%) and 3 reoperations (rate of 1.5%). The outcome was satisfactory in the majority of cases. Conclusions: A comprehensive review on intraoperative fractures in reverse shoulder arthroplasties is presented. Results suggest favorable outcomes for all treatment methods, with a modest further complication rate. This investigation may aid in the treatment decision-making for these complications

Dedicated multichannel readout ASIC coupled with single crystal diamond for dosimeter application

This paper reports on the tests of a low-noise, multi-channel readout integrated circuit used as a readout electronic front-end for a diamond multi-pixel dosimeter. The system is developed for dose distribution measurement in radiotherapy applications. The first 10-channel prototype chip was designed and fabricated in a 0.18 um CMOS process. Every channel includes a charge integrator with a 10 pF capacitor and a double slope A/D converter. The diamond multi-pixel detector, based on CVD synthetic single crystal diamond Schottky diodes, is made by a 3 × 3 sensor matrix. The overall device has been tested under irradiation with 6 MeV radio therapeutic photon beams at the Policlinico ``Tor Vergata'' (PTV) hospital. Measurements show a 20 fA RMS leakage current from the front-end input stage and a negligible dark current from the diamond detector, a stable temporal response and a good linear behaviour as a function of both dose and dose rate. These characteristics were common to each tested channel

On the measurement uncertainty of microdosimetric quantities using diamond and silicon microdosimeters in carbon-ion beams

Purpose: The purpose of this paper is to compare the response of two different types of solid-state microdosimeters, that is, silicon and diamond, and their uncertainties. A study of the conversion of silicon microdosimetric spectra to the diamond equivalent for microdosimeters with different geometry of the sensitive volumes is performed, including the use of different stopping power databases. Method: Diamond and silicon microdosimeters were irradiated under the same conditions, aligned at the same depth in a carbon-ion beam at the MedAustron ion therapy center. In order to estimate the microdosimetric quantities, the readout electronic linearity was investigated with three different methods, that is, the first being a single linear regression, the second consisting of a double linear regression with a channel transition and last a multiple linear regression by splitting the data into odd and even groups. The uncertainty related to each of these methods was estimated as well. The edge calibration was performed using the intercept with the horizontal axis of the tangent through the inflection point of the Fermi function approximation multi-channel analyzer spectrum. It was assumed that this point corresponds to the maximum energy difference of particle traversing the sensitive volume (SV) for which the residual range difference in the continuous slowing down approximation is equal to the thickness of the SV of the microdosimeter. Four material conversion methods were explored, the edge method, the density method, the maximum-deposition energy method and the bin-by-bin transformation method. The uncertainties of the microdosimetric quantities resulting from the linearization, the edge calibration and the detectors thickness were also estimated. Results: It was found that the double linear regression had the lowest uncertainty for both microdosimeters. The propagated standard (k = 1) uncertainties on the frequency-mean lineal energy y¯F${\bar{y}}_{\rm{F}}$ and the dose-mean lineal energy y¯D${\bar{y}}_{\rm{D}}$ values from the marker point, in the spectra, in the plateau were 0.1% and 0.2%, respectively, for the diamond microdosimeter, whilst for the silicon microdosimeter data converted to diamond, the uncertainty was estimated to be 0.1%. In the range corresponding to the 90% of the amplitude of the Bragg Peak at the distal part of the Bragg curve (R90 ) the uncertainty was found to be 0.1%. The uncertainty propagation from the stopping power tables was estimated to be between 5% and 7% depending on the method. The uncertainty on the y¯F${\bar{y}}_{\rm{F}}$ and y¯D${\bar{y}}_{\rm{D}}$ coming from the thickness of the detectors varied between 0.3% and 0.5%. Conclusion: This article demonstrate that the linearity of the readout electronics affects the microdosimetric spectra with a difference in y¯F${\bar{y}}_{\rm{F}}$ values between the different linearization methods of up to 17.5%. The combined uncertainty was dominated by the uncertainty of stopping power on the edge

Lateral IBIC characterization of single crystal synthetic diamond detectors

In order to evaluate the charge collection efficiency (CCE) profile of single-crystal diamond devices based on a p-type/intrinsic/metal configuration, a lateral Ion Beam Induced Charge (IBIC) analysis was performed over their cleaved cross sections using a 2 MeV proton microbeam. CCE profiles in the depth direction were extracted from the cross-sectional maps at variable bias voltage. IBIC spectra relevant to the depletion region extending beneath the frontal Schottky electrode show a 100% CCE, with a spectral resolution of about 1.5%. The dependence of the width of the high efficiency region from applied bias voltage allows the constant residual doping concentration of the active region to be evaluated. The region where the electric field is absent shows an exponentially decreasing CCE profile, from which it is possible to estimate the diffusion length of the minority carriers by means of a drift-diffusion model. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Array of time-of-flight diamond detectors for particle discrimination in laser driven p-11B fusion experiments

The detection of radiation emission in laser induced plasma experiments is an helpful method for gaining information on the physics of laser-matter interaction. Time-of-Flight (TOF) approach is a powerful and effective method to obtain timely spectra of particles accelerated from laser-generated plasma. To this respect, diamond-based detectors are very attractive due to their interesting features such as fast signal collection time, signal proportional to the energy deposited by the incident radiation, blindness to visible radiation, high radiation hardness and low leakage current at room temperature operation. Unfortunately, they cannot supply discrimination on the species of the incoming ions, but only their energies. This may be overcome using specific filtering foils to exploit the different stopping powers of ions of different species and energies. In this work we describe the method to distinguish particles using an array of TOF diamond detectors. A first prototype array, consisting of 2×2 diamond detectors, nominally identical and featuring by aluminum filters of different thicknesses, was developed and preliminary tested at PALS facility in Prague

A 3-dimensional interdigitated electrode geometry for the enhancement of charge collection efficiency in diamond detectors

In this work, a single crystal CVD diamond film with a novel three-dimensional (3D) interdigitated electrode geometry has been fabricated with the reactive ion etching (RIE) technique in order to increase the charge collection efficiency (CCE) with respect to that obtained by standard superficial electrodes. The geometrical arrangement of the electric field lines due to the 3D patterning of the electrodes results in a shorter travel path for the excess charge carriers, thus contributing to a more efficient charge collection mechanism. The CCE of the device was mapped by means of the ion beam induced charge (IBIC) technique. A 1MeV proton microbeam was raster-scanned over the active area of the diamond detector under different bias voltage conditions, enabling to probe the charge transport properties of the detector up to a depth of 8 ìm below the sample surface. The experimental results, supported by the numerical simulations, show a significant improvement in the 3D detector performance (i.e. CCE, energy resolution, extension of the active area) if compared with the results obtained by standard surface metallic electrodes