Spreading of Information on a Network: A Quantum View.

This paper concerns the modeling of the spread of information through a complex, multi-layered network, where the information is transferred from an initial transmitter to a final receiver. The mathematical model is deduced within the framework of operatorial methods, according to the formal mathematical apparatus typical of quantum mechanics. Two different approaches are considered: one based on the (H,ρ)-induced dynamics and one on the Gorini-Kossakowski-Sudarshan-Lindblad (GKSL) equation. For each method, numerical results are presented.

Predicting Difficult Airway Intubation Based on Maxillofacial Trauma: A Retrospective Study.

Purpose The purpose of this study was to determine which types of facial injuries in traumatic patients' wounds cause difficult intubation for anesthesiology team. By anticipating potential complications with airway management, the surgeons can be better prepared for emergent cricothyrotomy if needed. This could include prior to the planned procedure in the operating room (OR) as well as in emergent conditions in trauma bay. Methods Trauma patients with facial injuries in a level II trauma center from January 2007 to September 2017 that required intubation were evaluated for types of facial injury. Anesthesiology intubation documents were reviewed to determine which types of facial injuries were associated with difficult intubation per anesthesiology documentation. Results A total of 232 subjects were selected and it was found that patients with LeFort II facial fracture, bilateral mandibular fracture, and facial fracture associated with basilar skull fracture were noted to have difficult intubation by the anesthesiology team. Conclusion On the basis of CT imaging findings, our study demonstrates that certain types of facial fractures could pose difficult intubation. Surgeons should be aware of these injuries and be ready to intervene with emergent cricothyrotomy if necessary.

Mandibular Subcondylar Fracture: Improved Functional Outcomes in Selected Patients with Open Treatment.

BACKGROUND: Subcondylar fractures represent 25 to 35 percent of all mandibular fractures, yet the treatment paradigm has remained controversial. Closed treatment relies on the plasticity of the condyle head during recovery, whereas open treatment is challenging and risks facial nerve injury. Perioperative, functional, and patient-reported outcomes were measured to compare methods of open versus closed treatment of subcondylar fractures. METHODS: Selected displaced subcondylar fracture cases with open (open reduction and internal fixation of subcondylar fracture with maxillomandibular fixation) versus closed (maxillomandibular fixation) treatment were compared (n = 60). Demographics, perioperative data, complications, persistent symptoms, chin deviation, malocclusion, change in mouth opening, functional scores, and FACE-Q patient satisfaction were recorded. RESULTS: Open versus closed groups had similar demographics and perioperative data, except the open group had longer operating room time (76.39 minutes versus 56.15 minutes). In long-term follow-up, open-treated patients had fewer symptoms (9 percent versus 67 percent), less chin deviation (0 percent versus 40 percent), a less restricted mouth opening (3mm versus 5mm), and better functional scores (1.92 versus 0.861). Transient facial nerve weakness was seen in 6 percent of open cases. CONCLUSION: For selected subcondylar fracture patients, open treatment with endoscopic assistance, nerve monitoring, and specialized plates provides superior long-term results compared to closed treatment when considering symptoms and functional parameters. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Spreading of Competing Information in a Network.

We propose a simple approach to investigate the spreading of news in a network. In more detail, we consider two different versions of a single type of information, one of which is close to the essence of the information (and we call it good news), and another of which is somehow modified from some biased agent of the system (fake news, in our language). Good and fake news move around some agents, getting the original information and returning their own version of it to other agents of the network. Our main interest is to deduce the dynamics for such spreading, and to analyze if and under which conditions good news wins against fake news. The methodology is based on the use of ladder fermionic operators, which are quite efficient in modeling dispersion effects and interactions between the agents of the system.

Langerhans Cell Histiocytosis in the Pediatric Population: Treatment of Isolated Craniofacial Lesions.

Langerhans cell histiocytosis (LCH) commonly affects the craniofacial skeleton and prognosis depends on location, extension, and recurrence of the disease. The aim of our study is to better define the treatment of single craniofacial lesions, as to date different treatment modalities have been suggested and recurrence rates for both unifocal and multifocal bony lesion range between 10% and 70%. Between 2000 and 2014, we retrospectively reviewed clinical findings, anatomic location, extent of the disease, therapy, and outcomes in 24 pediatric patients with histologically confirmed LCH. Seventeen patients (67%) had craniofacial involvement, of which 13 had single system involvement and 4 had multisystem involvement. Eight patients (33%) had no craniofacial involvement. Eleven patients affected by unifocal cranial lesions were treated with resection and reconstruction. One patient with a unifocal mastoid lesion was treated with chemotherapy alone (vinblastine and prednisone). Four patients with mandible lesions were treated with curettage alone.There were no recurrences in patients treated with excision alone. One patient (25%) treated with curettage recurred. Two patients with diffuse disease manifested organ dysfunction and diabetes insipidus. Chemotherapy was tolerated in 12 patients treated.Our findings suggest that resection of isolated LCH lesions of the cranium is safe and chemotherapy is effective and well tolerated for nonsurgical cases.

Surgical Treatment for Palatoglossal Arch Cicatrix and Velopharyngeal Insufficiency After Adenotonsillectomy.

Postadenotonsillectomy velopharyngeal incompetence/insufficiency/dysfunction (VPI) is an uncommon but potentially surgically challenging problem. We report a child without cleft palate who developed severe palatoglossal arch cicatrix and VPI after adenotonsillectomy, and describe bilateral palatoglossal arch z-plasty to restore palatal function and speech.

Non-Hermitian Operator Modelling of Basic Cancer Cell Dynamics.

We propose a dynamical system of tumor cells proliferation based on operatorial methods. The approach we propose is quantum-like: we use ladder and number operators to describe healthy and tumor cells birth and death, and the evolution is ruled by a non-hermitian Hamiltonian which includes, in a non reversible way, the basic biological mechanisms we consider for the system. We show that this approach is rather efficient in describing some processes of the cells. We further add some medical treatment, described by adding a suitable term in the Hamiltonian, which controls and limits the growth of tumor cells, and we propose an optimal approach to stop, and reverse, this growth.

Burn scar regeneration with the "SUFA" (Subcision and Fat Grafting) technique. A prospective clinical study.

BACKGROUND: Treatment of burn scars with traditional surgical techniques is challenging due to recurrent contractures. Fat grafting has been previously used in small clinical series and results are often biased by lack of scientific validating methods. Fat grafting in clinical practice is often evaluated for its filler properties and rarely scientifically validated for its potential in dermal regeneration. Animal studies have shown dermal regeneration with new deposition and reorientation of the collagen fiber. Our study aims to apply the validity of in vitro studies to clinical practice. METHODS: Our study prospectively evaluated outcomes in 12 patients treated with the "SUFA" technique (Subcision and Fat Grafting) for debilitating contracted burns scars limiting range of motion. Results were evaluated clinically with the Vancouver scale and by range of motion at 1, 3, 6 and 12 months. Dermal regeneration was evaluated by looking at dermis thickening using high definition ultrasound and scar remodeling looking at reorientation and new deposition of collagen fibers with hematoxylin-eosin histology and monoclonal antibodies against collagen type 1 and 3. RESULTS: Statistically significant clinical improvements in range of motion of the affected joints was observed (P<0.05). Fat reabsorption occurred with a mean of 40%. Thickening of dermis and redistribution and reorientation of the collagen fibers within the dermis was also demonstrated. CONCLUSIONS: Our results present the first clinical scientific evidence of dermal regeneration in fat grafting. Using monoclonal antibodies and high definition ultrasounds, we demonstrate the first evidence of dermis regeneration in a clinical scenario.

A surgical approach to the craniofacial defects of Opitz G/BBB syndrome.

Opitz syndrome is a rare genetic disorder which has been well defined; however, the surgical treatment of the anomalies has not been codified. The objective is to review the literature and describe the surgical priorities in the treatment of Opitz syndrome. This report is unique in the fact that it describes a surgical approach to the treatment of the deformities. Better outcomes are achieved with preoperative analysis of the deformities and surgical planning. Simultaneous soft tissues and bony reconstruction with grafts can achieve long lasting results and decrease recurrence rates.

Improving Pressure Ulcer Reconstruction: Our Protocol and the COP (Cone of Pressure) Flap.

BACKGROUND: Surgical treatment of pressure ulcers is challenging for high recurrence rates. Deepithelialized flaps have been used previously with the aim to eliminate shearing forces and the cone of pressure (COP) effect. The goal of this study is to adopt a standardized protocol and evaluate if 2 different flap techniques affect outcomes. METHODS: The novel COP flap is illustrated. Twenty patients were prospectively treated with flap coverage over a 36-month period. According to the flap type, patients were assigned to 2 groups: group 1 with 11 patients treated with the COP flap and group 2 with 9 patients treated with conventional flap without anchoring technique. We adopted a standardized protocol of debridement, tissue cultures, and negative-pressure wound therapy. Rotation fasciocutaneous flaps were used for both groups and mean follow-up was 19 months. The COP flap is a large deepithelialized rotation flap inset with transcutaneous nonabsorbable bolster sutures. The 2 groups were comparable for demographics and ulcer location and size (P < 0.05). Five patients showed positive cultures and were treated with antibiotics and negative-pressure therapy before surgery. RESULTS: Recurrence rates were 12% in the COP flap group and 60% in the conventional flap coverage group (P < 0.001). Results were compared at 16-month follow-up. CONCLUSIONS: The COP flap significantly reduces recurrences and eliminates shearing forces, suture ripping, and tension on superficial soft-tissue layers. The technique can be applied to both ischial and sacral pressure sores. The flap provides padding over bony prominence without jeopardizing flap vascularity.

Large-scale effects of migration and conflict in pre-agricultural groups: Insights from a dynamic model.

The debate on the causes of conflict in human societies has deep roots. In particular, the extent of conflict in hunter-gatherer groups remains unclear. Some authors suggest that large-scale violence only arose with the spreading of agriculture and the building of complex societies. To shed light on this issue, we developed a model based on operatorial techniques simulating population-resource dynamics within a two-dimensional lattice, with humans and natural resources interacting in each cell of the lattice. The model outcomes under different conditions were compared with recently available demographic data for prehistoric South America. Only under conditions that include migration among cells and conflict was the model able to consistently reproduce the empirical data at a continental scale. We argue that the interplay between resource competition, migration, and conflict drove the population dynamics of South America after the colonization phase and before the introduction of agriculture. The relation between population and resources indeed emerged as a key factor leading to migration and conflict once the carrying capacity of the environment has been reached.

Platysma-based myocutaneous clavicular island flap for intraoral reconstruction.

The clavicular myocutaneous island flap, with circulation provided by the platysma and superficial cervical fascia, was first performed by Paul Tessier in 1970, taking his motivation from the prior experience of John Barron with subcutaneous island flaps. A manuscript written by Dr. Tessier on his experience of 120 cases using the flap (which we will refer to as the BT, or Barron-Tessier flap) has been translated and is presented, as well the experiences of Matthews and Wolfe, who learned the procedure from Dr. Tessier, and Kamerer, an ENT/Head and Neck surgeon who learned the procedure from Matthews. In aggregate, we will present our joint experience with 443 cases of the BT flap. Because of its ease and speed of harvest, reliability, and provision of thin, pliable skin, we feel that, in many instances, it is equivalent, or even superior to microsurgical free flap for reconstruction of intraoral lining defects.

Breast reduction with dermoglandular flaps: Tessier's "total dermo-mastopexy" and the "yin-yang technique".

The use of dermoglandular flaps in reduction mastopexy was advocated by Paul Tessier, who never published his method, but had actually almost finished the following article before his death in June 2008. Dr. Tessier is acknowledged as the "father" of craniofacial surgery, but he had interest in aesthetic surgery, and was quite proud of the technique he had developed using dermoglandular flaps in reduction mammoplasty. He had literally hundreds of techniques and methods that he had developed but which never found their way into print, both because of his enormous surgical schedule, and perhaps his self-imposed standards for anything that he published, which were almost impossibly high. The technique proposed by Dr. Gargano is similar in some ways to Dr. Tessier, it seemed good that they will be published together.

Salvage of exposed breast implant using capsular flaps.

OBJECTIVE: Extrusion represents potential complications associated with the use of breast implants. Attempts to salvage the exposed implants are rarely successful when poor tissue coverage or radiotherpy is present and therefore removal of implant and wound healing are mandatory. In these refractory complicated cases the use of capsular flaps can represent a useful tool to save the implant and achieve definitive healing. METHODS: Capsular flaps have been performed on 6 patients with implant extrusion and 11 patients with breast contour deformities over the last 6 years. The authors describe an innovative technique using capsular flaps which are harvested from thicker viable tissues and inset in multiple layers into the fistula tract to reinforce the breast envelope and prevent recurrence of implant extrusion. RESULTS: Complete healing and implant salvage were achieved in all patients treated. No major complications occurred and only minor contour deformities, that regressed spontaneously after surgery, were observed for 2 weeks. CONCLUSIONS: Although capsular flaps have been previously described to correct breast shape deformities, no previous report has yet suggested its utility in breast implant salvage in case of extrusion. The authors advocate the use of capsular flap to save the exposed breast implant especially when poor tissue coverage is present and other surgical options to save the implant have already failed.

Wrist arthrofibrosis.

Wrist arthrofibrosis is a condition of decreased range of wrist motion due to intrinsic adhesions and extrinsic contracture. It is clinically characterized by restricted wrist range of motion, pain, swelling, and a plateau in improvement after at least 6 months of intensive physiotherapy. Other conditions must be excluded, such as articular incongruity, arthritis, spasticity, skin and subcutaneous scarring, and loose bodies. We have devised a classification system based on pathologic anatomic location, where Type I represents intrinsic adhesions, and Type II represents extrinsic contracture. The types are subdivided according to where the pathology is present. The operative approach should be wrist arthroscopy for Types IA (radiocarpal adhesions) and IB (midcarpal adhesions) where intraarticular adhesions are present. Types IC (distal radioulnar joint adhesions) and II C (distal radioulnar joint capsular contracture) are best approached in an open manner where dorsal and palmar capsulectomies of the distal radioulnar joint are performed. For Types IIA, B, and D (dorsal, palmar, and combination extrinsic contracture, respectively), both open and arthroscopic methods are described.