Intervention with young voice users: A clinical perspective

This diverse group is described in relation to life stage, short- and long-range performance objectives, and lifestyle factors pertinent to vocal health. Physical, behavioral, cognitive, and psychosocial issues relevant to assessment and intervention will be addressed. The possible dissonance between a clinician's developmental perspective and a client's immediate pragmatic concerns is discussed. In addition, the specific challenges of dealing with adolescents (e.g., the influence of the peer group, the emergence of autonomy, the redefinition of relationships with significant adults, and the vulnerability of the mechanism) are related to clinical problem solving.     

怎样把3维流形嵌入5维空间

本文用一个相当初等的方法，说明了如何把一个３维流形嵌入到５维空间中去。     

CO laser applications in surgery

An investigation of the potential of CO lasers ( = 5–6 μm) in surgery is presented. CO laser radiation appears to have better cutting and coagulating characteristics than the CO₂ laser, which is currently widely used in medicine.     

Collagen injection in the scarred vocal fold

Scar tissue in the vocal fold can impair vibration and voice quality. The association of scarring and glottic insufficiency prompted our use of injectable bovine collagen in a variety of pathologic conditions exhibiting vocal fold scarring. Incremental augmentation and improved glottic function in several treated patients seemed to be facilitated by softening of scar tissue. Although the use of bioimplants in the larynx is associated with immunologic risks, the proclivity to soften scar tissue is one potential benefit of such materials. The biological activity of injectable collagen seems to alter local collagen metabolism by promoting ingrowth of host fibroblasts that are active in collagen degradation and synthesis. Further research to study the mechanisms whereby injectable collagen promotes remodeling of connective tissue might have significant therapeutic implications in the management of laryngeal scarring.     

Dehn surgeries on strongly invertible knots which yield lens spaces

In this article we show no Dehn surgery on nontrivial strongly invertible knots can yield the lens space for any integer . In order to do that, we determine band attaches to -torus links producing the trivial knot.

     

Intonation Drift in A Capella Soprano, Alto, Tenor, Bass Quartet Singing With Key Modulation

OBJECTIVES/HYPOTHESIS: When a soprano, alto, tenor, bass (SATB) quartet sings unaccompanied, or a capella, the members of the group will tend to make use of non-equal-tempered intonation to govern their tuning. If the music they are performing visits different keys and they do maintain non-equal-tempered tuning, then the pitch center will have to shift from its starting point, which is a necessary consequence of the physics behind the use of a non-equal-tempered tuning system. The implication of this shift for tuning in a capella singing is that it is not possible both to maintain accurate non-equal-tempered tuning and to stay in pitch throughout music that modulates in key. METHODS: To test this notion, a set of four-part exercises were written by the author that visit several different key chords in sequential progression. In each case, the starting and finishing chords were either identical or exactly an octave apart. Mean fundamental frequency values for each note were measured using four electrolaryngographs (one per singer), and the f0 data were normalized and plotted with respect to equal-tempered tuning to enable any overall tuning shift to be observed. RESULTS: The results indicate that singers do (1) tend to non-equal-tempered tuning and (b) do consequentially shift their intonation with modulation. CONCLUSIONS: These data indicate that pitch drift is potentially a necessary part of staying in-tune. Further work is required to identify items in the choral repertoire for which this effect is likely and then to inform the choral conducting and singing communities appropriately.     

心脏外科手术后脑梗死患者的影像学特点及相关因素分析

本文对心脏外科手术后脑梗死患者的影像学特点及发生脑梗死的相关因素进行探讨。选取本院心脏外科手术患者286例作为研究对象,术后34例发生脑梗死,按照手术方式的不同将脑梗死患者分为体外循环组(11例)和非体外循环组(23例),比较两组术后脑梗死的影像学特点,并对心脏外科手术后脑梗死的影响因素进行分析。研究发现,两组穿支梗死、分水岭梗死、多发梗死、陈旧梗死的发生率比较,差异无统计学意义(P>0.05);体外循环组皮层梗死的发生率明显低于非体外循环组,体外循环组大面积梗死、双侧梗死的发生率明显高于非体外循环组,差异有统计学意义(P<0.05)。经单因素分析,性别、空腹血糖、TC、TG、LDL-C、Hcy、吸烟、饮酒不是心脏外科手术后脑梗死的影响因素(P>0.05),年龄、文化程度、高血压病史、糖尿病为心脏外科手术后脑梗死的影响因素(P<0.05),经多因素二元Logistic回归分析,年龄高、文化程度低、高血压病史≥10、有糖尿病,是心脏外科手术后脑梗死的独立影响因素(P<0.05)。结果显示,体外循环手术常为大面积梗死、双侧梗死,症状较重,而非体外循环手术常为皮层梗死,且两者分水岭梗死较多,均与栓塞和低灌注有关。心脏外科手术后脑梗死与年龄高、文化程度低、高血压病史≥10、有糖尿病密切相关,早期给予针对性预防干预可能降低脑梗死的发生。     

Master surgery scheduling with consideration of multiple downstream units

We consider a master surgery scheduling (MSS) problem in which block operating room (OR) time is assigned to different surgical specialties. While many MSS approaches in the literature consider only the impact of the MSS on operating theater and operating staff, we enlarge the scope to downstream resources, such as the intensive care unit (ICU) and the general wards required by the patients once they leave the OR. We first propose a stochastic analytical approach, which calculates for a given MSS the exact demand distribution for the downstream resources. We then discuss measures to define downstream costs resulting from the MSS and propose exact and heuristic algorithms to minimize these costs.     

Augmentation of the Porcine Vocal Fold Using Autologous Composite Cervical Fascia and Fat Graft. Comparison Between the Transmuscular and Submuscular Approaches

Objectives

To assess the integration of an autologous composite fascia and fat graft implanted into the lamina propria of a porcine vocal fold using two different approaches.

Study Design

An experimental prospective study on the porcine larynx was conducted at a tertiary research institution.

Methods

An external cervical approach was used to expose the thyroid cartilage of 24 healthy minipigs under general anesthesia. The composite fascia/fat graft was implanted through two distinct approaches, transmuscular and submuscular. Animals were sacrificed at 7, 30, 90, and 180 days for macroscopic and histological study of the larynx. Graft integration and local inflammatory response were studied.

Results

The survival rate of the experimental model was 100% and all animals had local inflammatory response to the surgical procedure. Only 41.7% of the grafts placed inside the thyroarytenoid (TA) muscle fibers were identified postmortem, whereas 83.3% of the submuscular grafts remained intact.

Conclusions

Graft incorporation was better and there was less inflammation when the architecture of the TA muscle fibers was preserved. Graft extrusion was observed in the most of the cases where it was placed inside the muscle.