Considerations for an Extended Framework for Interactive Epoch-Era Analysis

AbstractEpoch-Era Analysis (EEA) is a framework that supports narrative and computational scenario planning and analysis for both short run and long run futures. Currently EEA is being applied to frame problems faced by the DoD's Engineered Resilient Systems (ERS) efforts. Because of the large amount of data that must be analyzed when extending EEA to large-scale problems, such as those posed by DoD, a “big data” problem is introduced. This motivates the need for extensions to EEA methods that overcome the computational and human cognition issues that arise as a result. The research presented here describes exploratory development of Interactive Epoch-Era Analysis (IEEA) methods, including human interface and reasoning considerations for epoch and era characterizations, as well as single and multi- epoch and era analyses. Visualization techniques and methods for mitigating computational resource restrictions that facilitate improved decision-making are also presented

The role of shear heating in producing crystal-poor obsidian

The reasons for obsidian's lack of phenocrysts (2 vol%) contain plagioclase and sanidine but sometimes lack quartz. Crystal-poor samples contain dominantly rounded phenocrysts indicative of resorption, whereas phenocrysts in crystal-rich samples contain sharp, defined corners. Thermal models of ascending, high-silica magma were run using COMSOL Multiphysics to assess temperature increases caused by shear heating, which could potentially resorb crystals. Models show large (>300 K) temperature increases at the conduit edges capable of resorbing crystals. Though model dike geometry is unrealistic, obsidian mineralogy and thermal modeling are consistent with shear heating-induced resorption during ascent of high-silica magmas.Master of Scienc

Early adoption of transoral robotic surgical program: preliminary outcomes.

OBJECTIVE: The objective of this study is to demonstrate the feasibility and safety of establishing a transoral robotic surgical (TORS) program in the post-Food and Drug Administration (FDA) approval setting. Early outcomes are compared with the previously reported results of pioneering centers. STUDY DESIGN: Clinical data from a prospective TORS study. SETTING: Academic university institution. SUBJECTS AND METHODS: Sixty-one patients treated with 63 TORS procedures. Main outcome measures: intraoperative times, margin status, complications, time to diet, and percutaneous endoscopic gastrostomy (PEG) tube retention rate. The authors also report oncologic outcomes on their first 30 patients. RESULTS: The spectrum of subsites included tongue base, tonsil, parapharyngeal space, retromolar trigone, supraglottis, and posterior pharyngeal wall. Surgical console time averaged 79 ± 53 minutes. After re-resection of 4 patients, final negative margin status was 94% (50/53). A subset of 30 patients with squamous cell carcinoma reaching an average of 18 months of follow-up had a local regional control rate of 97% with a disease-free survival rate of 90%. The PEG tube retention rate was 7%. Complications included 2 readmissions with dehydration, 1 aspiration pneumonia, and 2 with minor oropharyngeal bleeding. Ninety-one percent of patients resumed an oral diet by the first postoperative visit. CONCLUSION: The initiation of a TORS program in the post-FDA setting can be achieved in a safe and efficient manner. Early results of pioneering TORS centers are reproducible. Continued investigation of TORS as a treatment option for oropharyngeal carcinoma is warranted

Categories of First-Order Quantifiers

One well known problem regarding quantifiers, in particular the 1storder quantifiers, is connected with their syntactic categories and denotations. The unsatisfactory efforts to establish the syntactic and ontological categories of quantifiers in formalized first-order languages can be solved by means of the so called principle of categorial compatibility formulated by Roman Suszko, referring to some innovative ideas of Gottlob Frege and visible in syntactic and semantic compatibility of language expressions. In the paper the principle is introduced for categorial languages generated by the Ajdukiewicz’s classical categorial grammar. The 1st-order quantifiers are typically ambiguous. Every 1st-order quantifier of the type k \u3e 0 is treated as a two-argument functorfunction defined on the variable standing at this quantifier and its scope (the sentential function with exactly k free variables, including the variable bound by this quantifier); a binary function defined on denotations of its two arguments is its denotation. Denotations of sentential functions, and hence also quantifiers, are defined separately in Fregean and in situational semantics. They belong to the ontological categories that correspond to the syntactic categories of these sentential functions and the considered quantifiers. The main result of the paper is a solution of the problem of categories of the 1st-order quantifiers based on the principle of categorial compatibility

Single institution implementation of permanent 131Cs interstitial brachytherapy for previously irradiated patients with resectable recurrent head and neck carcinoma

Purpose: Permanent interstitial brachytherapy is an appealing treatment modality for patients with locoregional recurrent, resectable head and neck carcinoma (HNC), having previously received radiation. Cesium-131 (131Cs) is a permanent implant brachytherapy isotope, with a low average photon energy of 30 keV and a short half-life of 9.7 days. Exposure to medical staff and family members is low; patient isolation and patient room shielding are not required. This work presents a single institution’s implementation process of utilizing an intraoperative, permanent 131Cs implant for patients with completely resected recurrent HNC. Materials & Methods: Fifteen patients receiving 131Cs permanent seed brachytherapy were included in this analysis. The process of pre-planning, selecting the dose prescription, seed ordering, intraoperative procedures, post-implant planning, and radiation safety protocols are described. Results: Tumor volumes were contoured on the available preoperative PET/CT scans and a pre-implant treatment plan was created using uniform source strength and uniform 1 cm seed spacing. Implants were performed intraoperatively, following tumor resection. In five of the fifteen cases, intraoperative findings necessitated a change from the planned number of seeds and recalculation of the pre-implant plan. The average prescription dose was 56.1 ±6.6 Gy (range, 40-60 Gy). The average seed strength used was 2.2 ±0.2 U (3.5 ±0.3 mCi). Patients returned to a recovery room on a standard surgical floor and remained inpatients, without radiation safety restrictions, based on standard surgical recovery protocols. A post-implant treatment plan was generated based on immediate post-operative CT imaging to verify the seed distribution and confirm delivery of the prescription dose. Patients were provided educational information regarding radiation safety recommendations. Conclusions: Cesium-131 interstitial brachytherapy is feasible and does not pose major radiation safety concerns; it should be considered as a treatment option for previously irradiated patients with recurrent, resectable HNC

Virtual Surgical Planning in Subscapular System Free Flap Reconstruction of Midface Defects.

OBJECTIVES: Reconstruction of the midface has many inherent challenges, including orbital support, skull base reconstruction, optimizing midface projection, separation of the nasal cavity and dental rehabilitation. Subscapular system free flaps (SF) have sufficient bone stock to support complex reconstruction and the option of separate soft tissue components. This study analyzes the effect of virtual surgical planning (VSP) in SF for midface on subsite reconstruction, bone segment contact and anatomic position. MATERIALS AND METHODS: Retrospective cohort of patients with midface defects that underwent SF reconstruction at a single tertiary care institution. RESULTS: Nine cases with VSP were compared to fourteen cases without VSP. VSP was associated with a higher number of successfully reconstructed subunits (5.9 vs 4.2, 95% CI of mean difference 0.31-3.04, p = 0.018), a higher number of successful bony contact between segments (2.2 vs 1.4, 95% CI of mean difference 0.0-1.6, p = 0.050), and a higher percent of segments in anatomic position (100% vs 71%, 95% CI of mean difference 2-55%, p = 0.035). When postoperative bone position after VSP reconstruction was compared to preoperative scans, the difference in anteroposterior, vertical and lateral projection compared to the preoperative \u27ideal\u27 bone position was82% of measurements. There were no flap losses. CONCLUSION: VSP may augment SF reconstruction of the midface by allowing for improved subunit reconstruction, bony segment contact and anatomically correct bone segment positioning. VSP can be a useful adjunct for complex midface reconstruction and the benefits should be weighed against cost

A systematic review of treating recurrent head and neck cancer: a reintroduction of brachytherapy with or without surgery.

Purpose: To review brachytherapy use in recurrent head and neck carcinoma (RHNC) with focus on its efficacy and complication rates. Material and methods: A literature search of PubMed, Ovid, Google Scholar, and Scopus was conducted from 1990 to 2017. Publications describing treatment of RHNC with brachytherapy with or without surgery were included. The focus of this review is on oncologic outcomes and the safety of brachytherapy in the recurrent setting. Results: Thirty studies involving RHNC treatment with brachytherapy were reviewed. Brachytherapy as adjunctive treatment to surgical resection appears to be associated with an improved local regional control and overall survival, when compared with the published rates for re-irradiation utilizing external beam radiotherapy (RT) or brachytherapy alone. Safety data remains variable with different isotopes and dose rates with implantable brachytherapy demonstrating a tolerable side effect profile. Conclusions: Although surgery remains a mainstay treatment for RHNC, intraoperative interstitial brachytherapy delivery as adjunctive therapy may improve the treatment outcome and may be associated with fewer complication rates as compared to reirradiation using external beam radiotherapy. Further investigations are required to elucidate the role of brachytherapy for RHNC

Novel Irradiated Axial Rotational Flap Model in the Rodent

Abstract Objectives: To design an easily reproducible rodent rotational skin flap and to evaluate the effects of radiation on flap viability. Methods: Ten rats received 40 Gy irradiation to the abdominal wall. Following a recovery period of one month, a 3 X 8 cm fasciocutaneous flap based axially on the inferior epigastric vessel, was raised and rotated 60 degrees into a contralateral deficit. Five non-irradiated rats underwent the identical procedure as a control. Animals were sacrificed seven days postoperatively, areas of flap necrosis were documented, and histological specimens were taken to compare flap viability and vessel density. Results: 60% of the rats in the irradiated group had necrosis of the distal flap ranging from 1 to 6 cm from the distal edge, whereas none of the animals (0%) in the control group exhibited necrosis (p\u3c0.001). Histology revealed collagen and vascular changes in the irradiated skin. Vascular density analysis revealed a significant difference between radiated and non-radiated flaps; p = 0.004, 0.029 and 0.014 in the distal, middle and proximal segments of the flap respectively. Conclusion: This novel rat axial rotational flap model demonstrates increases flap necrosis and a decrease in vascular density due to the effects of radiation. Using a linear electron accelerator a dose of 40 gy can be delivered to the skin without resulting in devastating gastrointestinal side effects

Mutation signature analysis identifies increased mutation caused by tobacco smoke associated DNA adducts in larynx squamous cell carcinoma compared with oral cavity and oropharynx.

Squamous cell carcinomas of the head and neck (HNSCC) arise from mucosal keratinocytes of the upper aero-digestive tract. Despite a common cell of origin and similar driver-gene mutations which divert cell fate from differentiation to proliferation, HNSCC are considered a heterogeneous group of tumors categorized by site of origin within the aero-digestive mucosa, and the presence or absence of HPV infection. Tobacco use is a major driver of carcinogenesis in HNSCC and is a poor prognosticator that has previously been associated with poor immune cell infiltration and higher mutation numbers. Here, we study patterns of mutations in HNSCC that are derived from the specific nucleotide changes and their surrounding nucleotide context (also known as mutation signatures). We identify that mutations linked to DNA adducts associated with tobacco smoke exposure are predominantly found in the larynx. Presence of this class of mutation, termed COSMIC signature 4, is responsible for the increased burden of mutation in this anatomical sub-site. In addition, we show that another mutation pattern, COSMIC signature 5, is positively associated with age in HNSCC from non-smokers and that larynx SCC from non-smokers have a greater number of signature 5 mutations compared with other HNSCC sub-sites. Immunohistochemistry demonstrates a significantly lower Ki-67 proliferation index in size matched larynx SCC compared with oral cavity SCC and oropharynx SCC. Collectively, these observations support a model where larynx SCC are characterized by slower growth and increased susceptibility to mutations from tobacco carcinogen DNA adducts

Taking Free Flap Surgery Abroad: A Collaborative Approach to a Complex Surgical Problem.

Accessibility to health care, especially complex surgical care, represents one of the major health care disparities in developing countries. While surgical teams may be willing to travel to these areas to help address these needs, there are many logistical and ethical dilemmas inherent in this pursuit. We reviewed our approach to the establishment of the team-based surgical outreach program, wherein we perform head and neck free tissue transfer surgery in Haiti. We describe the challenges encountered in the delivery of surgical care as well as ethical dilemmas relevant to surgical outreach trips, highlighting an approach reliant on strong local cooperation. Despite the obstacles in place, our experience shows that free flap surgery can be successfully and ethically performed in these areas of great need