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An 18 year old man was referred to the otolaryngology (head and neck surgery) department with persistent right sided nasal congestion for one year. He had used a nasal corticosteroid spray in the six months before presentation, but his symptoms had not improved. At the otolaryngology department he underwent a non-contrast computed tomography scan of his sinuses (fig 1). What is the diagnosis? Fig 1 Computed tomography scans of the sinuses (coronal planes) Antrochoanal polyps (ACPs) in the right sinonasal cavity (fig 2). Fig 2 Computed …

A 49 year old woman was referred to a community hospital after experiencing persistent purulent nasal discharge for three years. She had not responded to antibiotics. Subsequently, she was referred to a department of otolaryngology for surgical intervention. She underwent a non-contrast computed tomography (CT) scan of her sinuses (fig 1⇓). Based on the CT scan, what is the diagnosis? Fig 1 Coronal computed tomography (CT) scan of the sinus A fungal ball, also known as a mycetoma, in the right nasal cavity. ### Discussion The coronal sinus CT scan shows a fungal ball in the right nasal cavity …

Summary In this paper, we consider the optimal topology for leader-following consensus problem of continuous-time and discrete-time multi-agent systems based on linear quadratic regulator theory. For the first-order multi-agent systems, we propose a quadratic cost function, which is independent of the interaction graph, and find that the optimal topology is a star topology. For the second-order multi-agent systems, a quadratic cost function is also constructed, whereas the optimal topology for second-order leader-following consensus problem is an unevenly weighted star topology. The universality of these findings means that if each follower is connected with the leader, the information exchange between followers is unnecessary and insufficient. Simulation examples are provided to illustrate the effectiveness of the theoretical results. Copyright © 2014 John Wiley & Sons, Ltd.

For their unique properties and good solubility for many different materials, ionic liquids (ILs) have been applied in several fields, such as separation process, synthesis, catalysis and electrochemistry. This paper focuses on applications of ILs in organic pollutants control. An overview of separation, recycling and control of organic pollutants with ILs is present, for example, phenolic compounds, polycyclic aromatic hydrocarbon (PAHs) and dyes from wastewater, dioxins from waste gas, polyamides from solid wastes, chlorophenothane (DDT) and dieldrin from contaminated soils. Furthermore, the problems and challenges of ILs in organic pollutants control are discussed.

A highly sensitive amperometric sulfadiazine sensor based on coating multiwalled carbon nanotubes (MWCNTs) and N-octyl-pyridinium-hexafluorophosphate (OPPF(6)) ionic liquid composite on a glassy carbon (GC) electrode is described. The MWCNTs/OPPF(6) composite contributed new properties to electrochemical sensors by combining the advantages of both ionic liquids and MWCNTs. Compared with bare GC electrode, the electrocatalytic activity of MWCNTs/OPPF(6) generated a greatly improved electrochemical detection of sulfadiazine including low oxidation potential, high current responses, and good anti-fouling performance. The oxidation peak currents of sulfadiazine obtained on the MWCNTs/OPPF(6) coated GC electrode were proportional to the concentration of sulfadiazine within the range of 3.3-35.4 μM with a detection limit of 0.21 μM.

It is typical in containment control problems to assume that there is no conflict of interest among leaders. In this paper, we consider the situation where there is conflict between leaders; namely, the leaders compete to attract followers. The strategies of each leader are defined by choosing at most k followers to propagate their information. Then, we formulate a standard two-player zero-sum game by using graph theory and matrix theory. We further prove that each player will choose exactly k followers when the game achieves a Nash equilibrium. It is noteworthy that the interaction graph here is generated from the conflict between leaders and then the Nash equilibrium point of the game corresponds to the equilibrium topology. For the case of choosing one follower, a necessary and sufficient condition for an interaction graph to be the equilibrium topology is derived. Moreover, we can obtain the equilibrium topology directly if followers’ interaction graph is a circulant graph or a graph with a center vertex. Simulation examples are provided to validate the effectiveness of the theoretical results.

The diagnosis and management of pediatric cerebrospinal fluid (CSF) leak and encephalocele are challenging. The current study aimed to identify patient characteristics, review operative techniques, and evaluate the efficacy and safety of endoscopic endonasal repair in a pediatric population. We retrospectively reviewed the records of pediatric patients who underwent transnasal endoscopic repair of CSF leak with or without a meningocele or an encephalocele at Beijing Tongren Hospital, Capital Medical University, between July 2003 and May 2014. All patients had preoperative radiological evaluations and underwent endoscopic endonasal repair of their skull base defects. Altogether, 23 children (mean age 7.0 years) underwent the procedures. Sixteen cases were congenital, and 7 patients had trauma history. The herniations or defects included meningoencephaloceles in 15 cases, meningoceles in 4 cases, and CSF leak in 4 cases (2 patients had bilateral leaks). The leak or herniation sites were ethmoid roof in 10 patients (one was bilateral), cribriform plate in 5, lateral to the foramen cecum in 3, posterior wall of the frontal sinus in 1, sphenoid sinus in 2, lateral recess of the sphenoid sinus in 1, and sella turcica base in 2. All subjects had favorable clinical outcomes without recurrence during a follow-up of 6–123 months (mean 61.1 months). The endoscopic endonasal approach was the preferred method for repairing CSF leaks with or without an encephalocele in pediatric patients. Compared to traditional operations, this endoscopic procedure is minimally invasive, efficient, and safe.

This paper considers optimal control for the firstorder multi-agent systems with leaders. Based on linear quadratic regulator theory, we propose a quadratic cost function which is independent of the interaction graph. For the leader-following consensus problem, the optimal control corresponds to a star topology. For the containment control problem, the optimal control is obtained by solving a series of convex optimization problems. Simulation examples are provided to illustrate the effectiveness of the theoretical results.

The paper analyzes language education policy from the perspective of national culture benefit. The aim of paper is to answer some questions such as: what logical relations exist between national culture benefit and language education policy? What influences on each other? What is the theoretical basis while analyzing language education policy from the view of national culture benefit? Furthermore, the paper would structure theoretical frame of language education policy in order to maintain benefits of national culture and establish theoretical basis for the following text.

In this paper, a stochastic optimal model of the exploration of exhaustible resources has been established with the aim to maximize the profit of extraction and by the assumption that both the price and the reserve of resource following the geometric Brownian motion. The HJB equation of the model and its economics explanation are deduced. Moreover, it is shown that the price of the exhaustible resource is equal to the sum of the extracted cost and its shadow rent.

A highly sensitive amperometric sulfadiazine sensor based on coating multiwalled carbon nanotubes (MWCNTs) and N-octyl-pyridinium-hexafluorophosphate (OPPF(6)) ionic liquid composite on a glassy carbon (GC) electrode is described. The MWCNTs/OPPF(6) composite contributed new properties to electrochemical sensors by combining the advantages of both ionic liquids and MWCNTs. Compared with bare GC electrode, the electrocatalytic activity of MWCNTs/OPPF(6) generated a greatly improved electrochemical detection of sulfadiazine including low oxidation potential, high current responses, and good anti-fouling performance. The oxidation peak currents of sulfadiazine obtained on the MWCNTs/OPPF(6) coated GC electrode were proportional to the concentration of sulfadiazine within the range of 3.3-35.4 μM with a detection limit of 0.21 μM.

To discuss the role of image navigation in resection of the ossifying fibroma of paranasal sinuses and anterior skull base with nasal endoscope.Fourteen cases with ossifying fibroma involving paranasal sinuses and anterior skull base were underwent intranasal endoscopic surgery under the guidance of image navigation. Sequential nasal sinuses CT scans were obtained before and after operation. CT scans demonstrated that the nasal septum, orbital wall and anterior skull base were involved in every case. The anterior boundary of the frontal recess cells was involved in 10 cases. The lesions were adjacent to the orbital apex and optic canal in 5 cases. The sella turcica and clivus were invaded in 3 cases and the pterygopalatine fossa was invaded in 2 cases.The tumors were thoroughly removed in all cases. The average operative time was 280 minutes and the average registration time of navigation was 9 minutes. Postoperation CT scans demonstrated that the tumors were totally resected.The image-guided endoscopic surgery of the ossifying fibroma of paranasal sinuses and anterior skull base provided accurate tumor resection, increased surgical effectiveness, decreased overall surgical complications.

A 28-day study was conducted to evaluate changes in urinary cytokine/chemokine expression levels in dogs with renal injury due to administration of cisplatin. Animals (n=17) were administered cisplatin at 0.75 mg/kg/day (i.v.) for five consecutive days. Urine/serum were collected at pre-dosing, 4h post-dosing and on days 2, 3, 4, 8, 10, 14, 16, 18, 21, 23, 25, 28 and unscheduled terminations. Animals were euthanized when serum creatinine (sCr) levels measured at ≥ 1.9 mg/dL, indicating significant loss of renal function (decreased glomerular filtration rate). Relevant clinical observations included lethargy and dehydration. Pre-study sCr levels ranged from 0.6 to 0.8 mg/dL; on days 1 through 4, sCr levels ranged from 0.5 and 1.1mg/dL; and terminal sCr levels ranged from 0.6 and 6.6 mg/dL. Histologically, cisplatin-related renal changes were characterized as proximal tubule dilatation, vacuolization, degeneration, regeneration, and interstitial inflammation. Increased interleukin (IL)-2, IL-8, monocyte chemoattractant protein-1 (MCP-1), granulocyte-macrophage colony-stimulating factor (GMCSF) and keratinocyte-derived chemokine (KC) occurred on days 3 through 4. Increased IL-7 occurred on day 4. This study showed for the first time that inflammatory cytokines/chemokines in urine positively identified acute renal tubular injury in dogs at time points earlier than sCr, a traditional marker of nephrotoxicity.