Towards Improved QUBO Formulations of IR Tasks for Quantum Annealers

In recent years the interest in applying Quantum Computing to Information Retrieval and Recommendation Systems task has increased and several papers have proposed formulations of relevant tasks that can be solved with quantum devices (community detection, feature selection etc.), usually focusing on Quantum Annealers (QA), a special purpose device able to solve combinatorial optimization problems. However, most research only focuses on the mathematical aspect of the formulation, without accounting for the underlying physical processes of the quantum device. Indeed, theoretical studies indicate that certain characteristics make a problem difficult to solve on QA, but it is not clear how to use this knowledge to inform the development of better problem formulations that are equivalent but easier to solve on QA. This work presents a preliminary study which approaches this issue with an empirical perspective. We consider several problems both general and related to IR and Recommendation tasks to assess whether we can identify characteristics of the problem formulation or the solution space that affect the effectiveness of QA. The results indicate interesting correlations and suggest that this is a promising area to investigate further

Does the structure of the QUBO problem affect the effectiveness of quantum annealing? An empirical perspective

In recent years there has been a significant interest in exploring the potential of Quantum Annealers (QA) as heuristic solvers of Quadratic Unconstrained Binary Optimization (QUBO) problems. Some problems are more difficult to solve on QA and understanding why is not straightforward, because an analytical study of the underlying physical system is intractable for large QUBO problems. This work consists in an empirical analysis of the features making a QUBO problem difficult to solve on QA, based on clusters of QUBO instances identified with Hierarchical Clustering. The analysis reveals correlations between specific values of the features and the ability of QA to solve effectively the instances. These initial results open new research opportunities to inform the development of new AI methods supporting quantum computation (e.g., for minor embedding or error mitigation) that are better tailored to the characteristics of the problem, as well as to develop better QUBO formulations for known problems in order to improve the quality of the solutions found by QA

Three-dimensional minimally invasive video-assisted thyroidectomy: preliminary report

Three-dimensional (3D) minimally invasive video-assisted thyroidectomy (MIVAT) was carried out with a 4-mm, 3D 0-degree stereoscopic endoscope. The procedure was applied on 3 patients who underwent total thyroidectomy and data were prospectively collected. Operative time for total thyroidectomy ranged from 72 to 90 minutes. Neither intra-nor post-operative complications were reported during the study. The surgical team noticed a good perception of depth and easy recognising of anatomic structures, especially concerning the upper and lower vascular pedicle, the parathyroids, the superior and inferior laryngeal nerves. Preliminary impression emerging from this study seems to suggest that 3D MIVAT is safe and effective. Future studies with larger case series are required to determine the role of this procedure

Role of Narrow Band Imaging Endoscopy in Preoperative Evaluation of Laryngeal Leukoplakia: A Review of the Literature

Introduction: Leukoplakia is a precancerous lesion considered to be within the spectrum of histopathological results from parakeratosis, through stages of dysplasia to invasive cancer. Narrow band imaging (NBI) endoscopy has been introduced to improve early diagnosis of benign and malignant laryngeal lesions. The aim of this literature review was to evaluate the accuracy of preoperative evaluation of vocal fold leukoplakia with NBI endoscopy in comparison with histology. Methods: A systematic review of the literature was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using 3 different databases: PubMed, Embase, and Scopus. The included articles in the systematic review were identified combining each of the following terms: “narrow band imaging” OR “NBI,” [AND] with each of these terms: “laryngeal leukoplakia,” OR “vocal fold leukoplakia,” OR “vocal cord leukoplakia.” Results: The articles that fully met the inclusion criteria were 5 case series, conducted between January 2010 and February 2018, and published between 2017 and 2019. The selected articles included 312 patients (86% males and 14% females), affected by 382 vocal cord leukoplakia, evaluated with NBI endoscopy and that underwent surgical microlaryngoscopy with biopsy. Based on the studies included in the review, accuracy of NBI in predicting malignancy within leukoplakia ranged from 81% to 97.8%, demonstrating to be an accurate method to predict the risk of malignant transformation of vocal fold leukoplakia. Conclusion: Narrow band imaging can help otolaryngologists in the decision-making process on the necessity to perform a biopsy and transoral surgery or long-term follow-up. Larger studies are necessary to confirm the high association of NBI evaluation of the epithelium surrounding the leukoplakia with the histological diagnosis

Free Flaps for Advanced Oral Cancer in the Older Old and Oldest Old : A Retrospective Multi-Institutional Study

Introduction: Surgery followed by adjuvant therapy represents the most adequate treatment for advanced oral squamous cell carcinoma (OSCC). Free flaps are considered the best reconstructive option after major oral surgery. In the last decades, OSCC has increased in the elderly due to an augmented life span. The aim of this work is to evaluate the feasibility of microvascular surgery in patients older than 75 years, focusing on clinical and surgical prognosticators. Methods: "Older old" (aged >= 75) and "oldest old" (>85) patients who underwent microvascular reconstruction for OSCC from 2002 to 2018 were retrospectively evaluated in three referral Head and Neck Departments. Demographic, clinical, and surgical data were collected and analyzed. Pre-operative assessment was performed by ASA and ACE-27 scores. Complications were grouped as medical or surgical, an d major or minor according to the Clavien-Dindo scale. Results: Eighty-four patients (72 "older old" and 12 "oldest old") were treated with a free flap success rate of 94.1%. Thirty-seven (44.7%) and nine (10.7%) patients had minor and major medical complications, respectively; 18 (21.4%) and 17 (20.2%) had minor and major surgical complications, respectively. Twenty-one (25%) patients had both medical and surgical complications (with a statistically significant association, p = 0.018). Overall, 52 (61.9%) patients had at least one complication: ASA score, diabetes mellitus, and duration of general anesthesia (DGA) significantly impacted the complication rate at multivariate analysis. Conclusion: Our data confirm the feasibility of free flaps for OSCC reconstruction in appropriately selected elderly patients. Pre-operative assessment and aggressive management of glycemia in patients with diabetes is mandatory. DGA should be reduced as much as possible to prevent post-surgical complications. Comprehensive geriatric assessment is of paramount importance in this subset of patients

Influence of different lipid emulsions on specific immune cell functions in head and neck cancer patients receiving supplemental parenteral nutrition: An exploratory analysis.

Abstract Objectives The effect of diet on immune responses is an area of intense investigation. Dietary lipids have been shown to differently influence and fine-tune the reactivity of immune cell subsets, thus potentially affecting clinical outcomes. Patients with head and neck squamous cell carcinoma face malnutrition, due to swallowing impairment related to the tumor site or to treatment sequalae, and may need supplemental parenteral nutrition (SPN) in addition to oral feeding when enteral nutrition is not feasible. Additionally, immune depression is a well-known complication in these patients. Parenteral nutrition (PN) bags contain amino acids, minerals, electrolytes and mostly lipids that provide calories in a concentrated form and are enriched with essential fatty acids. The aim of this study was to investigate multiple parameters of the immune responses in a cohort of patients with head and neck squamous cell carcinoma undergoing supplemental PN with bags enriched in ω-3 or ω-9 and ω-6 fatty acids. Methods To our knowledge, this was the first exploratory study to investigate the effects of two different PN lipid emulsions on specific immune cells function of patients with advanced head and neck squamous carcinoma. ω-3-enriched fish-oil-based- and ω-6- and ω-9-enriched olive-oil-basedSPN was administered to two groups of patients for 1 wk in the context of an observational multicentric study. Polychromatic flow cytometry was used to investigate multiple subsets of leukocytes, with a special focus on cellular populations endowed with antitumor activity. Results Patients treated with olive-oil-based PN showed an increase in the function of the innate (natural killer cells and monocytes) and adaptive (both CD4 and CD8 cells) arms of the immune response. Conclusion An increase in the function of the innate and adaptive arms of the immune response may favor antitumoral responses

Lembo miofasciale di vasto laterale nella ricostruzione della lingua

Nell'ultimo decennio il lembo antero-laterale di coscia (ALT) è diventato il lembo libero più utilizzato nella ricostruzione della lingua, dal momento che esso è caratterizzato da bassa morbidità a livello del sito donatore e da migliori risultati estetici. Tuttavia, l'ALT fascio-cutaneo può essere insufficiente nella ricostruzione nei difetti maggiori (es. glossectomia totale) mentre la sua variante muscolo-cutanea (che include il muscolo vasto laterale)' può essere troppo voluminosa. Scopo dello studio è quello di descrivere la nostra esperienza preliminare nella ricostruzione della lingua utilizzando il lembo libero mio-fasciale di vasto laterale che potrebbe a nostro parere offrire notevoli vantaggi nella ricostruzione testa-collo come: possibilità di confezionare un lembo voluminoso quando necessario, ottimi risultati funzionali, obliterazione di spazi morti con prevenzione dello sviluppo di fistola e infezione con minima morbidità a livello del sito donatore

Multicentric prospective study on the prevalence of sublevel IIB metastases in head and neck cancer

Objective: To evaluate the prevalence of sublevel IIB lymph node (LN) metastases for head and neck primary tumors in a large cohort of patients. Design: Prospective study. Setting: One referral university hospital and 2 national institutes of oncology. Patients: Between 2003 and 2005, 297 patients (male to female ratio, 3.5:1; mean age, 58.8 years [range, 18-89 years]) affected by head and neck cancer were treated by surgery on the primary tumor and/or the neck. Primary site distribution included the following: oral cavity in 111 patients, larynx in 92, oropharynx in 32, thyroid gland in 22, skin of the lateral face or scalp in 16, hypopharynx in 11, unknown primary in 7, and parotid gland in 6. Sublevel IIB was evaluated for the number of LNs and pathologic N (pN) status. Interventions: All patients underwent unilateral or bilateral neck dissection (ND) with therapeutic or elective intent according to the primary site and clinical T (cT) and clinical N (cN) status. Sublevel IIB was selectively dissected at the beginning of ND, labeled, and processed independently. Main Outcome Measures: The distribution of metastases among the different levels was analyzed. The influence of several factors (institution in which the surgical procedure was performed, sex of the patient, site of primary, histotype, pathologic T [pT] status, cN status, lower level involved in the neck together with sublevel IIB, association with sublevel IIA metastasis, ipsilateral number of involved levels, and previous surgical treatment limited on the primary site) on the prevalence of sublevel IIB metastasis was statistically evaluated by the Pearson \u3c72 test or Fisher exact test. Results: A total of 443 NDs were performed (unilateral in 151 patients and bilateral in 146). Among the patients, the tumors were staged cN0/pN0 in 27%,cN+/pN+ in 50%, cN+/pN0 in 7%, and cN0/pN+ in 16%. The mean number of LNs collected at sublevel IIB was 5.4 (range, 0-24). The overall prevalence of sublevel IIB metastases was 5.6% (26 neck sides). Tumor histologic type in the sublevel IIB+ population was squamous cell carcinoma in 80%, papillary carcinoma in 8%, melanoma in 8%, and adenocarcinoma in 4%. The \u3c72 test showed a significantly higher risk for LN metastases at sublevel IIB in patients affected by parotid gland primary tumors (33%), tumors of the skin or scalp (25%), unknown primary tumors (14%), and cancers of the oral cavity (10%) (P=.02) and in those clinically staged as cN+ (P<.001). Conclusions: Sublevel IIB dissection is strongly recommended for all patients with cN+ tumors and in those affected by tumor of the parotid gland, skin, and scalp scheduled for elective ND. Patients affected by laryngeal cancer scheduled for elective ND can be considered the ideal candidates for preservation of sublevel IIB. However, whether this policy could be associated with a better functional outcome remains to be demonstrated by prospective studies on a large series of patients