We investigated the spontaneous healing process of a surgically created supraspinatus tendon tear in rabbits with specific reference to the expression of matrix metalloproteinase-2 (MMP-2) and its time-course change in enzymatic activity along with the expression of tissue inhibitors of metalloproteinases (TIMPs). A transverse, full thickness tear of the supraspinatus tendon was created and examined. Immunohistochemical analysis revealed that MMP-2 positive cells were mainly localized at both cutting ends of the tendon, and reparative tissue encroached into the gap from the bursa1 side. The expression of TIMP-1 was induced in the cells at not only the tendon edges but also the reparative tissue during the healing process. TIMP-2 was constitutively expressed in both the tendon and the reparative tissue. Gelatin zymography using tissue culture media demonstrated latent and active forms of MMP-2 and characteristic time-linked changes of the enzymatic activity. Western blotting confirmed the bands as the latent form of MMP-2. These results suggest that MMP-2 is expressed and activated during the healing process of acute supraspinatus tendon tear and can play an important role in the remodeling process.

Background Retention treatment is reportedly associated with lower infection control rates than two-stage revision. However, the studies on which this presumption are based depend on comparisons of historical rather than concurrent controls. Questions/purposes We (1) asked whether the infection control rates, number of additional procedures, length of hospital stay, and treatment duration differed between implant retention and two-stage revision treatment; and (2) identified risk factors that can contribute to failure of infection control. Methods We reviewed the records of 60 patients treated for 64 infected TKA from 2002 to 2007. Twenty-eight patients (32 knees) underwent débridement with retention of component, and 32 patients (32 knees) were treated with component removal and two-stage revision surgery. We determined patients' demographics, type of infection, causative organisms, and outcome of treatment. Mean followup was 36 months (range, 12-84 months). Results Infection control rate was 31% in retention and 59% in the removal group after initial surgical treatment, and 81% and 91% at latest followup, respectively. Treatment duration was shorter in the retention group and there was no difference in number of additional surgeries and length of hospital stay. Type of treatment (retention versus removal) was the only factor associated with infection control; subgroup analysis in the retention group showed Staphylococcus aureus infection and polyethylene nonexchange as contributing factors for failure of infection control. Conclusions Although initial infection control rate was substantially lower in the retention group than the removal group, final results were comparable at latest followup. We believe retention treatment can be selectively considered for non-S. aureus infection, and when applied in selected patients, polyethylene exchange should be performed. Level of Evidence Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

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Context:Groin pain is a common entity in athletes involved in sports that require acute cutting, pivoting, or kicking such as soccer and ice hockey. Athletic pubalgia is increasingly recognized as a common cause of chronic groin and adductor pain in athletes. It is considered an overuse injury predisposing to disruption of the rectus tendon insertion to the pubis and weakness of the posterior inguinal wall without a clinically detectable hernia. These patients often require surgical therapy after failure of nonoperative measures. A variety of surgical options have been used, and most patients improve and return to high-level competition.Evidence Acquisition:PubMed databases were searched to identify relevant scientific and review articles from January 1920 to January 2015 using the search terms groin pain, sports hernia, athletic pubalgia, adductor strain, osteitis pubis, stress fractures, femoroacetabular impingement, and labral tears.Study Design:Clinical review.Level of Evidence:Level 4.Results and Conclusion:Athletic pubalgia is an overuse injury involving a weakness in the rectus abdominis insertion or posterior inguinal wall of the lower abdomen caused by acute or repetitive injury of the structure. A variety of surgical options have been reported with successful outcomes, with high rates of return to the sport in the majority of cases.

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The onset conditions for bubbles and blobs are investigated by analyzing the Communication/Navigation Outage Forecasting System satellite/Coupled Ion‐Neutral Dynamics Investigation instrument data on 2 March 2009. A series of bubbles and blobs are detected in the longitude regions 180°–240°E and 240°–295°E, respectively. Bubbles are detected at low latitudes before midnight. Blobs are detected at 14°–25° magnetic latitude, between 2300 and 0500 LT in the altitude range of 400–480 km. The distinguishing feature in the longitude region where bubbles are detected is an enhancement in background plasma density with respect to that in the longitude region where bubbles are absent. Blobs are detected in a longitude region where fluctuations in the plasma density exist over a broad latitude range. The total ion density (and O+ density) and H+ density perturbations are in‐phase at the locations of bubbles and out of phase at the locations of blobs. Bubbles are not detected in the longitude region where blobs are detected. The different characteristics of bubbles and blobs and their creation under different geophysical conditions indicate that creation of blobs need not be associated with bubbles.

Neural machine translation (NMT) has been a new paradigm in machine translation, and the attention mechanism has become the dominant approach with the state-of-the-art records in many language pairs. While there are variants of the attention mechanism, all of them use only temporal attention where one scalar value is assigned to one context vector corresponding to a source word. In this paper, we propose a fine-grained (or 2D) attention mechanism where each dimension of a context vector will receive a separate attention score. In experiments with the task of En-De and En-Fi translation, the fine-grained attention method improves the translation quality in terms of BLEU score. In addition, our alignment analysis reveals how the fine-grained attention mechanism exploits the internal structure of context vectors.

We first observe a potential weakness of continuous vector representations of symbols in neural machine translation. That is, the continuous vector representation, or a word embedding vector, of a symbol encodes multiple dimensions of similarity, equivalent to encoding more than one meaning of the word. This has the consequence that the encoder and decoder recurrent networks in neural machine translation need to spend substantial amount of their capacity in disambiguating source and target words based on the context which is defined by a source sentence. Based on this observation, in this paper we propose to contextualize the word embedding vectors using a nonlinear bag-of-words representation of the source sentence. Additionally, we propose to represent special tokens (such as numbers, proper nouns and acronyms) with typed symbols to facilitate translating those words that are not well-suited to be translated via continuous vectors. The experiments on En-Fr and En-De reveal that the proposed approaches of contextualization and symbolization improves the translation quality of neural machine translation systems significantly.