Blind beamforming-based strong interference suppression in underwater acoustic direct-sequence code-division multiple-access systems.

In an underwater acoustic direct-sequence code-division multiple-access (DS-CDMA) system, the performance of the conventional receiver is severely limited by the strong multiple-access interferences, which is due to the near-far effect. In this paper, a time-frequency-time with eigendecomposition-based blind beamformer (TFT-EBB) method is proposed for a distant user to suppress strong interference from a nearby user in DS-CDMA underwater acoustic communications. When the interference level is moderately higher than that of the desired signal, the TFT-EBB method can estimate the composite steering vector of all multipath components of the weak desired user signal via the eigendecomposition of the array covariance matrix at each frequency bin. Then the proposed energy detection-based RAKE receiver is cascaded to achieve multipath diversity, in which it requires less prior information compared with the conventional RAKE receiver. The proposed method is evaluated by using both simulated and field experimental data, which verifies its effectiveness.

One-Year Relapse of Mandibular Distraction for Hemifacial Microsomia Using Masseteric Botulinum Toxin Type A Injections.

BACKGROUND: The relapse of hemifacial microsomia was thought to be highly related to the soft tissue envelope around the mandible angle mainly composed by masseter and medial pterygoid. According to the reason, we tried to apply masseter injection of type A botulinum toxin to weaken the soft envelope tension on the early stage post mandible distraction in adult HFM patients. METHODS: Eight patients diagnosed with HFM were studied and randomly assigned to an experimental or control group. Patients in the experimental group were treated with DO, orthognathic surgeries, autologous fat grafting, and bilateral masseter muscle injection with type A botulinum toxin. The patients in control group were treated with the same procedures as the patients in experimental group except for masseter muscle injection with type A botulinum toxin. The recurrence rates of both groups were evaluated and analyzed after nearly 1 year of follow-up. RESULTS: The mean recurrence rate was 26.30% ±â€Š11.84% (range 7.62%-37.27%) in the 8 patients after 1-year follow-up. The relapse rate was 16.32% ±â€Š7.78% (7.62%-26.22%) in the experimental group and 36.28% ±â€Š1.03% (34.84%-37.27%) in the control group. There was a significant difference (P = 0.002) between the experimental group and the control group. CONCLUSIONS: The combination of DO, orthognathic surgeries, autologous fat particle transplantation, and masseter muscle type A botulinum toxin injection technique could be a comprehensive treatment plan for adult patients of HFM. Furthermore, masseter injection of type A botulinum toxin might be an alternative method to reduce the early recurrence rate of postoperative adult patients of HFM.

Evaluation of human platelet lysate and dimethyl sulfoxide as cryoprotectants for the cryopreservation of human adipose-derived stem cells.

Cryopreservation provides an effective technique to maintain the functional properties of human adipose-derived stem cells (ASCs). Dimethylsulfoxide (DMSO) and fetal bovine serum (FBS) are frequently used as cryoprotectants for this purpose. However, the use of DMSO can result in adverse effects and toxic reactions and FBS can introduce risks of viral, prion, zoonose contaminations and evoke immune responses after injection. It is therefore crucial to reduce DMSO concentrations and use serum-free solution in the cryopreservation process. Human platelet lysate (PL) is a promising candidate for use as an alternative to DMSO and FBS. Therefore, in this study, with an aim to identify a cryoprotective agent for ASC cryopreservation, we determined the viability, proliferation potential, phenotype, and differentiation potential of fresh ASCs and ASCs cryopreserved using different combinations of three cryoprotective agents: fetal bovine serum (FBS), dimethylsulfoxide (DMSO), and human platelet lysate (PL). The viability of the ASCs cryopreserved with 90% FBS and 10% DMSO, 95% FBS and 5% DMSO, and 97% PL and 3% DMSO was >80%, and the proliferation potentials, cell phenotypes, and differentiation potentials of these groups were similar to those of fresh ASCs. Together, our findings suggest that a combination of 97% PL and 3% DMSO is an ideal cryoprotective agent for the efficient cryopreservation of human ASCs.

[Mandibular distraction combined with orthognathic techniques for the correction of adult hemifacial microsomia].

OBJECTIVE: To study the combination of Mandibular distraction and orthognathic techniques for the reconstruction of adult hemifacial microsomia. METHODS: The three-dimensional CT reconstruction data was used with Mimics for preoperation design. The osteotomy location, distraction vector, distraction distance were decided before operation with a surgical guider. At the first stage, internal distractor was implanted after ostetomy through an extra-oral approach. The distraction begun 5-7 days after operation with a frequency of 1 mm/day. After distraction, the distractor was maintained for 3-6 months. At the second stage, the distractor was removed. Le Fort I osteotomy was performed in order to correct the cross-bite and improve the facial contour. Usually, bone graft was inserted into the gap after Le Fort I osteotomy. The genioplasty was also performed if necessary. RESULTS: 9 cases of adult hemifacial microsomia with severe mandibular deviation were treated. The facial asymmetry were improved greatly. 1 patient suffered an wound infection in the maxillary region after Le Fort I osteotomy and healed uneventfully with wound irrigation. CONCLUSIONS: Mandibular distraction combined with orthognathic surgery is an effective procedure for adult hemifacial microsomia with complicated mandibular hypoplasia.

Accident entry of titanium screw into the sphenoid sinus during paranasal augmentation with porous polyethylene implant.

We report a rare case of accident entry of titanium screw into the sphenoid sinus during paranasal augmentation with porous polyethylene implant. The screw was finally retrieved from the sphenoid sinus by a nasal endoscope. We emphasize that, on this surgery region, the simple fixation skill must be performed delicately. Otherwise, an adverse event may still happen.

[The plastic surgery for plagiocephaly].

OBJECTIVE: To sum up three types of plastic procedures for frontal plagiocephaly Based on the principle of floating forehead, the plagiocephaly (unilateral coronal synostosis). METHODS: was corrected and orbito-frontal reconstruction was performed by orbito-frontal advancement, 'or temporoparietal osteotomy, or fronto-parietal osteotomy. The absorbable plates and microscrews composed of From January 2008 to polylactide polymers, were used to immobilize calvarial segments. RESULTS: December 2010, 9 cases of plagiocephaly were treated with satisfactory result and no severe complication. The patients were followed up for 1-2 years with no recurrence of suture fusion and deformity. The brain development was not restricted. The absorbable plates were applied to avoid the metal fixation moving into The three types of plastic procedures, orbito-frontal advancement, or the cranial bone. CONCLUSIONS: temporo-parietal osteotomy, or fronto-parietal osteotomy, can correct the plagiocephaly with satisfactory orbito-frontal appearance. Long-term follow-up is needed to observe the long-term effect of the orbito-frontal reconstructive operation on mental and calvarial development as well as visual function.

[Skeleton and soft tissue contour reconstruction for severe progressive hemifacial atrophy].

OBJECTIVE: To sum up the various procedures for skeleton and soft tissue contour reconstruction in severe progressive hemifacial atrophy. METHODS: From Jan 2004 to May 2012, 25 patients with severe progressive hemifacial atrophy underwent the procedures of lipoinjection, microsurgical flap transplantation, dermis grafting, distraction osteogenesis, orthognathic surgery and so on for both skeleton and soft tissue reconstruction. RESULTS: Among them, zygomatic augmentation and lipoinjection were performed in 24 cases, anterolateral thigh adipofascial flap in 10 cases and latissimus dorsi flap in one case, orthognathic surgery in 17 cases, including Le Fort I osetoectomy in 3 cases, genioplasty in 4 cases, mandibular distraction osteogenesis combined with secondary Le Fort I osteotomy in 3 cases, genioplasty combined with mandibular augmentation with Medpor implant in 7 cases. The patients were followed up for 6 months to 5 years. Through skelton and soft tissue reconstruction, the oblique occlusion plane and malocclusion were corrected with great improvement in face asymmetry. CONCLUSIONS: For severe progreassive hemifacial atrophy, comprehensive procedures should be adopted for both skelton and soft tissue reconstruction to achieve good results.