Interference alignment (IA) is a joint-transmission technique that achieves the maximum degrees-offreedom (DoF) of the interference channel, which provides linear scaling of the capacity with the number of users for high signal-to-noise ratios (SNRs). Most prior work on IA is based on the impractical assumption that perfect and global channel-state information (CSI) is available at all transmitters. To implement IA, each receiver has to feed back CSI to all interferers, resulting in overwhelming feedback overhead. In particular, the sum feedback rate of each receiver scales quadratically with the number of users even if the quantized CSI is fed back. To substantially suppress feedback overhead, this paper focuses on designing efficient arrangements of feedback links, called feedback topologies, under the IA constraint. For the multiple-input-multiple-output (MIMO) K-user interference channel, we propose the feedback topology that supports sequential CSI exchange (feedback and feedforward) between transmitters and receivers so as to achieve IA progressively. This feedback topology is shown to reduce the network feedback overhead from a quadratic function of K to a linear one. To reduce the delay in the sequential CSI exchange, an alternative feedback topology is designed for supporting two-hop feedback via a control station, which also achieves the linear feedback scaling with K. Next, given the proposed feedback topologies, the feedback-bit allocation algorithm is designed for allocating feedback bits by each receiver to different feedback links so as to regulate the residual interference caused by the finite-rate feedback. Simulation results demonstrate that the proposed bit allocation leads to significant throughput gains especially in strong interference environments.

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Double Patterning lithography is very fascinating way of lithography which is capable of pushing down the k1 limit below 0.25. By using double patterning lithography, we can delineate the pattern beyond resolution capability. Target pattern is decomposed into patterns within resolution capability and decomposed patterns are combined together through twice lithography and twice etch processes. Two ways, negative and positive, of doing double patterning process are contrived and studied experimentally. In this paper, various issues in double patterning lithography such as pattern decomposition, resist process on patterned topography, process window of 1/4 pitch patterning, and overlay dependent CD variation are studied on positive and negative tone double patterning respectively. Among various issues about double patterning, only the overlay controllability and productivity seemed to be dominated as visible obstacles so far.

Hunter syndrome (mucopolysaccharidosis II, MPS II) is a rare, X-linked disorder of glycosaminoglycan (GAG) catabolism caused by a deficiency in the activity of the lysosomal enzyme, iduronate-2-sulfatase (I2S). In this study, the medical records of 75 Korean patients with Hunter syndrome (74 males, 1 female) were retrospectively reviewed to investigate the frequency of organ involvement and survival at a single center. The three most common symptoms of organ involvement were hepatosplenomegaly (99%), facial dysmorphism (97%), and frequent otitis media (91%). Cardiovascular involvement was also common including valvular abnormalities (89%), left ventricular hypertrophy (68%), and hypertension (30%). The 19 patients who died had a median age of 16.8 years at the time of death. Four of them died within 1 year of the start of enzyme replacement therapy; autopsy showed myocardial infarction with severe coronary artery disease in one patient. Two other patients died due to pneumonia and sleep apnea. In one case, the cause of death was not investigated. The high incidence of hypertension, and the presence of valvular heart disease indicates that close cardiac monitoring is mandatory in all patients with Hunter syndrome, especially relatively older patients even if they are being treated with enzyme replacement therapy.

Although carpal tunnel syndrome (CTS) is the most common compressive neuropathy seen in the upper extremity of adults, it is rarely seen in children. Several reports have shown that mucopolysaccharidosis type II (Hunter syndrome), a rare genetic disorder, is one of the causes of CTS in children. Usual symptoms of CTS are pain, weakness, and paresthesias in the hand and digits. However, the diagnosis of CTS in Hunter syndrome is often delayed or unrecognized because of atypical symptoms and cognitive impairment. Here, we report the prevalence, clinical manifestation, and nerve conduction profiles of CTS in 45 Hunter syndrome patients. The mean age of the study participants was 117.1 (74.9) months (range: 4-408 months); all patients were male. Forty-three (96.0%) of the 45 patients with Hunter syndrome had CTS. Bilateral CTS was observed in all patients; 73 (82.0%) of the patients' hands had severe degree of CTS. Intriguingly, in contrast with other nerve velocities, decreases in forearm conduction velocities of the median nerve were observed in 28 (31.5%) of 89 hands with CTS. There was a significant difference in age (P < 0.001) between hands with normal, mild, moderate, and severe grades of CTS. The compound muscle action potential and sensory nerve action potential amplitudes of the median nerves decreased with age (CMAP, r = -0.526, P < 0.001; SNAP, r = -0.564, P < 0.001). Early recognition and intervention to ameliorate the symptoms of CTS are important in improving the quality of life of Hunter syndrome patients.

In this paper, we study the basic locus in the fiber at p of a certain unitary Shimura variety with a certain parahoric level structure. The basic locus M ss is uniformized by a formal scheme N which is called Rapoport-Zink space. We show that the irreducible components of the induced reduced subscheme N red of N are Deligne-Lusztig varieties and their intersection behavior is controlled by a certain Bruhat-Tits building. Also, we define special cycles in N and study their intersection multiplicities. Contents 1. Introduction 1.1. The local result : relative Rapoport-Zink spaces 1.2. The global result: non-archimedean uniformization 1.3. Special cycles 2. The moduli space N of strict formal O F -modules 2.1. The moduli space N h E/F (r, n − r) 2.2. Description of the points of N 2.3. Description of the points of N II 2.4. The sets R Λ , S Λ indexed by vertex lattices Λ. 3. Subschemes N Λ of N 3.1. Strict formal O F -modules X Λ + and X Λ − 3.2. Subschemes N Λ attached to vertex lattices Λ 3.3. Deligne-Lusztig varieties 3.4. The Deligne-Lusztig variety Y Λ 3.5. Description of the points of N Λ 3.6. The isomorphism between N Λ and Y Λ 3.7. Regularity of N 3.8. The global structure of N : the Bruhat-Tits stratification 3.9. The moduli space N h E/K (r, n − r) 4. Uniformization of unitary Shimura varieties 4.1. The Shimura data 4.2. Integral models 4.3. The uniformization theorem Date: July 27, 2018.1 2 SUNGYOON CHO 5. Special cycles and arithmetic intersection numbers 43 References 53

We report here the effect of micro-environmental changes from biodegradable magnesium alloys on the activities of cells - osteoblasts, osteoclasts and macrophages - which play critical roles in each phase of the bone-regeneration process. Despite positive bone formation effects from several in vivo studies, minimal progress has been made in identifying underlying mechanisms through in vitro studies, which are currently concentrated on osteoblastic activities. The observed in vitro and in vivo results indicated that alkaline pH and released magnesium and zinc ions derived from Mg-5 wt% Ca-1 wt% Zn alloy biodegradation promote the progress of bone formation. In contrast, alkaline pH and magnesium ions remarkably suppressed osteoclastic activities and pro-inflammatory cytokine production, closely related to osteolysis and prosthesis failure. Findings from the present study conclude that the degradation of Mg-5 wt% Ca-1 wt% Zn alloys can promote new bone formation by simultaneously affecting the complex combination of variable cellular activities and phases. Copyright © 2016 John Wiley & Sons, Ltd.

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