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Objectives This study aimed to compare the differences in vocal quality between Mandarin-speaking children with cochlear implants and normal-hearing peers and to understand which cochlear implant usage parameters may predict unfavourable voice outcomes. Design A cross-sectional, case-controlled study. Setting A tertiary medical centre. Participants Thirty-five pre-lingually deaf children (age = 10.3 ± 1.6 years; 17 boys and 18 girls) who had used cochlear implants for >2 years and 35 age- and gender-matched controls with normal hearing. Main outcome measures Through sustained phonation of /a/ and reading of the Hare and Tortoise passage, the subjects' voice quality was analysed with aerodynamics and acoustics. A six-point scale was used for auditory-perceptual evaluation. A Pediatric Voice-Related Quality of Life Survey was filled out by the caregivers. Results The implanted subjects had significantly lower mean airflow rate (P = 0.006), higher phonation threshold pressure (P

The versatility of a novel scaling approach in quantifying the structure of model well-defined 3-arm star polyethylene molecules is presented. Many commercial polyethylenes have long side branches, and the nature and quantity of these branches varies widely among the various forms. For instance, low-density polyethylene (LDPE) is typically a highly branched structure with broad distributions in branch content, branch lengths and branch generation (in hyperbranched structures). This makes it difficult to accurately quantify the structure and the inherent structure-property relationships. To overcome this drawback, model well-defined hydrogenated polybutadiene (HPB) structures have been synthesized via anionic polymerization and hydrogenation to serve as model analogues to long-chain branched polyethylene. In this article, model 3-arm star polyethylene molecules are quantified using the scaling approach. Along with the long-chain branch content in polyethylene, the approach also provides unique measurements of long-chain branch length and hyperbranch content. Such detailed description facilitates better understanding of the effect of branching on the physical properties of polyethylene. © 2012 American Chemical Society.

Silver-facilitated ethylene/ethane separation was successfully accomplished using supported liquid membrane in a membrane contactor configuration. Ethylene flux increased with increasing driving force. The effect, however, gradually leveled of at higher driving forces (>100 psi) due to the limitation of the ethylene/silver complexation equilibrium. Increases in liquid side pressure resulted in a slight initial drop in ethylene flux that quickly leveled of to a constant value as more liquid pressure was applied. The reason for this drop may be a combination of two-phase flow effects and a change in the gas-liquid interface area. Varying liquid circulation rate showed two distinct regions of permeation behavior. At low liquid flow rate, the ethylene permeation is limited by the rate at which the carrier solution is delivered to the flash pot. In this region, ethylene flux increases with increasing liquid flow rate. At high liquid flow rates the ethylene flux is at a maximum and is limited by diffusion through the membrane wall. Ethylene transport is also affected by the fiber morphology (porosity and tortuosity) resulting from different spinning conditions

Twenty-nine patients (24 males, 5 females; aged 62.8 +/- 10.1 years) with noninsulin-dependent diabetes mellitus (NIDDM) without gallstones and impaired liver function were included in our study. The patients were categorized by blood sugar control and disease duration. Twelve normal controls (10 males, 2 females; aged 62.8 +/- 12.4 years) were also studied for comparison. The gallbladder filling fraction (FF) and ejection fraction (EF) were calculated following the method of Krishnamurthy et al. The results showed no significant difference (P > 0.5) between (1) NIDDM and normal controls in FF (69.1 +/- 29.4 versus 67.5 +/- 24.0%) and EF (45.0 +/- 23.5 versus 54.8 +/- 10.0%) by a t-test, (2) good and poor blood sugar control in FF (64.9 +/- 30.9 versus 73.7 +/- 26.4%) and EF (42.0 +/- 25.4 versus 54.8 +/- 10.0%) by a Mann-Whitney U test, (3) long and short disease durations in FF (70.9 +/- 29.7 versus 67.9 +/- 28.7%) and EF (37.9 +/- 20.7 versus 50.0 +/- 24.1%) by a Mann-Whitney U test. In conclusion, the results challenge some previous reports and warrant further research.

Brittle matrix composites, including carbon-carbon (C-C) and ceramic matrix, offer a new dimension in the area of high-temperature structural materials. Fiber-matrix interactions determine the mechanism of the load transfer between the fiber and matrix and resulting mechanical properties. Composites studied in this work include a C-C composite densified with a chemical vapor infiltration (CVI) pyrolytic carbon, silicon carbide fiber-silicon carbide matrix composite, and carbon fiber-silicon carbide matrix composites densified by the CVI technique. The type of the interfacial carbon in C-C composites was found to control their mechanical properties. The presence of the compressive stress exerted by the matrix on the carbon fibers was attributed to an increase in flexural strength. The transverse matrix cracking in C/SiC composites was believed to cause a lowering in the flexural strength value. Brittle fracture behavior of SiC/SiC composites was correlated with the presence of an amorphous silica layer at the fiber-matrix interface.

The oral hypoglycemic agent sulfonylurea (SU) can increase plasma leptin concentrations. Additionally, diabetic subjects frequently have an altered plasma status of selected minerals. However, whether these described plasma parameters are changed in Type 2 diabetic patients who exhibit SU inefficacy has not yet been evaluated. In this preliminary study, fasting blood samples were collected from 16 Type 2 diabetic patients with secondary SU failure. As controls, 16 sex-, age- and adiposity-matched diabetic patients, who had similar diabetic duration and optimal glycemic control by SU, were also recruited. The results show that plasma values of leptin, C-peptide, calcium, magnesium, copper, and zinc did not significantly differ in these diabetic patients with or without secondary SU failure. However, the gender effect on plasma leptin level and the correlations between leptin and adiposity and C-peptide were retained. This study indicates that there is no relation between SU inefficacy and the plasma status of leptin and selected minerals.

It is found that the 2-index potential in nonabelian theories does not behave geometrically as a connection but that, considered as an element of the second de Rham cohomology group twisted by a flat connection, it fits well with all the properties assigned to it in various physical contexts. We also prove some results on the Euler characteristic of the twisted de Rham complex. Finally, provided that some conditions are satisfied, we propose a non-Abelian generalisation of S-duality., 11 pages, Latex; to appear in Repts. on Math. Phys

Nicalon fiber is the primary reinforcement in SiC-SiC composites currently produced by a variety of techniques including CVI and polymer infiltration. Low strength retention and dimensional change at high temperatures of the Nicalon fibers limits the choice of manufacturing processes which can be employed to produce low cost SiC-SiC composites. MER has developed a SiC reinforcement based upon the conversion of low cost carbon fabric to SiC via a Chemical Vapor Reaction (CVR) process. These new SiC filaments exhibit excellent creep resistance at temperatures up to 1600°C. SiC-SiC composites were fabricated using different types of graphite fabric converted to SiC fabric utilizing the CVR process combined with a polycarbosilane (PCS) infiltration and CVI densification. In addition, enhancement of the composite through-the-thickness thermal conductivity was accomplished via boron doping of the matrix. A correlation between processing conditions, microstructure and properties of the SiC-SiC composites will be presented.

The true existence of a disease entity termed "institutional colon" has remained controversial. The present study serves to test whether this entity actually exists and how frequently psychiatric and neurologic diseases are associated with colonic dysmotility.Using the hospital discharge records of four million US military veterans, we investigated the comorbid occurrence of volvulus, impaction of intestine, constipation, and megacolon with any neurologic or psychiatric disease.Comorbidity of colonic and neurologic/psychiatric diseases in identical subjects occurred two to three times more often than one would expect from the overall distribution of each group of diseases alone. Presenile dementia and Alzheimer's disease, Parkinson's disease, multiple sclerosis, and quadriplegia were associated significantly with all four colonic diseases. The various forms of schizophrenia coincided mostly with megacolon and constipation. Major depressive disorder was associated only with constipation, but with none of the other colonic diseases.Psychiatric and neurologic diseases are frequently associated with colonic dysmotility. The association raises the possibility of a pathophysiologic link involving the neuronal control of colonic motility.

Bone mineral density (BMD) in 38 male patients with noninsulin-dependent diabetes mellitus (NIDDM) was measured by dual photon absorptiometry (DPA) using a MSE OsteoTech 300 scanner. The BMD of the second to fourth lumbar vertebrae was measured and the mean density was presented as g cm-2. The patients were distinguished according to the following three criteria: (1) blood sugar control was good or poor; (2) the duration of diabetes was long or short; (3) renal function was evaluated by effective renal plasma flow (ERPF) as good or poor. The results showed about half the cases of NIDDM had lower BMD. The patients with poor blood sugar control, longer disease duration and poor renal function had lower BMD. However, the difference between any two groups distinguished by the three criteria is not significant. We think that the causes of osteoporosis in patients with NIDDM may not be explained by only a single factor.

In this study, we collected twenty NIDDM patients with impaired sensation and clinically suspected angiopathy over both lower extremities. All the patients underwent testing by means of the ultrasonic Doppler technique and were separated into two groups, group 1 with impaired blood flow, and group 2 with no significant impairment of blood flow. Ten normal persons were also included in this study (group 3). The results of the 133Xe muscle clearance test showed that the Q value of group 1 was 0.85 +/- 0.24 [mean +/- SE, ml (100g tissue min-1)], 1.05 +/- 0.31 in group 2 and 1.78 +/- 0.23 in group 3 of normal controls. After statistical analysis, there were significant differences in groups 1 and 2 relative to group 3 (p0.05), respectively. This preliminary result indicates that the 133Xe muscle clearance test may be an effective and convenient method to evaluate angiopathy of lower extremities in patients with NIDDM.

The Xe-133 clearance method is used to measure muscle blood flow in the lower limbs to establish normal values and evaluate the variance between different sex and age groups in healthy Chinese. 99 healthy volunteers were included in this study and divided into three groups according to age and two groups according to sex. Group I:40 y/o, 34 persons; Group II: 41-60 y/o, 30 persons; Group III:60 y/o, 35 persons; male group: 51 persons; and female group: 48 persons. Intramuscular injection of Xe-133 saline solution in the anterior tibial muscle of the right leg was performed in all the volunteers to calculate muscle blood flow. The muscle blood flow is 3.21 +/- 1.29 ml/100 gm/min in Group I, 3.19 +/- 1.28 in Group II, 2.71 +/- 1.17 in Group III, 3.09 +/- 1.38 in male, and 2.96 +/- 1.24 in female. There was no significant difference in Groups I and II, or in the male and female groups using the Student's t test for unpaired data. However, a mild difference was observed between Groups I and III, and between Groups II and III (P values of 0.09 and 0.11 respectively). We conclude that there is no variance of muscle blood flow in the lower limbs between different sexes and the effect of aging on peripheral muscle blood flow is not significant before 60 in healthy Chinese.

It is known that patients with hyperthyroidism have a lower zinc content in their erythrocytes, and that this decrement returns to normal after treatment with anti-thyroid drugs. This study was designed to investigate the alteration of body zinc levels in thyroid disorder. Two groups of out-patients associated with hyperthyroidism or hypothyroidism, and a group of normal healthy controls were collected. Zinc contents in the blood, hair and 24-hour urine samples were determined by a flame atomic absorption spectrometer. The results showed that patients with hyperthyroidism had a lower erythrocyte zinc level and an increased urinary zinc excretion (p0.05). The hypothyroidism had a higher hair zinc content and a decrement in urinary zinc excretion (p0.05). Body zinc levels, excluding the plasma zinc, held a certain correlation to the plasma thyroid hormones levels. The urinary zinc levels showed a more parallel variation in the thyroid disorders (p0.05). This data indicates that the alteration of urinary zinc levels might be a useful index for thyroid disorder evaluation. Body zinc could also play a physiological role in the metabolic regulation(s) of a thyroid disorder.

Zinc is known to have important effects on insulin activity, to increase the body fat deposition, and thyroid hormones conversion (T4 to T3). It is also known to have intestinal absorption competition between zinc and copper. This study was to investigate the blood zinc and copper concentrations in NIDDM and obesity, the relationships among metals, insulin, and thyroid hormones were also determined. Blood samples of diabetic, obese, and healthy individuals were collected between 9-10 AM, and the blood levels of zinc, copper, insulin, T4 and T3 were assayed. The results showed that diabetics and obese individuals had higher insulin and T3 levels than healthy controls, but there was no difference in T4. The obese had lower serum zinc concentration. There were low levels of copper both in serum and erythrocyte, and a low erythrocyte zinc concentration in NIDDM. Blood zinc concentration was inversely related to T3 level in diabetics and obese individuals. It is suggested that zinc, insulin and T3 may have considerable correlations in the thermoregulation on NIDDM and obesity, and the true mechanisms still need more further studies in the future.

Foot infection is a common cause of hospitalization for diabetic patients. Our study aimed to analyze patients' age, sex, the primary sites of infection, presenting features, outcome, bacteriologic studies and their clinical significance in diabetic foot infections. The age of our diabetic patients with foot infections ranged from 43 to 82 years, with a mean of 62.5 years; fifty-two of them were males and twenty-eight were females. The male to female ratio was 1.9:1, but there was no statistically significant difference between the sexes (p greater than 0.05). The commonest age group was the seventh decade of life (47.5%), followed by the sixth decade (32.5%). The commonest primary site of infection was the toes (53.8%), followed by foot area other than toe (25%) and the leg area was the least frequent (21.2%). Cellulitis combined with other foot lesions presented in 78.8% of these patients, foot ulcers in 75% of them, gangrenous change in 68%, necrotizing cellulitis or fasciitis in 16.3%, abscess formation in 12.5% and osteomyelitis in 7.5%. The legs were amputated in 53 patients (66.3%), usually below the knee (in 47.5%). We found that patients with a long history of DM had statistically significantly higher rate of amputation (p less than 0.01) than patients with only a brief history. Bacterial cultures from the infected foot lesions yielded numerous organisms in 58.8% of cases and a single organism in 31.1% of cases. Proteus mirabilis was the commonest organism isolated, followed by E. coli, Pseudomonas aeruginosa. The commonest month of the onset of diabetic foot infection was January, followed by February.

Insulinoma is a rare disease, which frequently causes hypoglycemic symptoms and signs or even shock. However, other diseases that produce similar symptoms and signs should firstly be ruled out. We describe a 63 years old male veteran who suffered from repeated episodes of seizure and conscious disturbance upon fasting, on and off for 8 years. Serial examinations led to the suspicion that this might be a case of insulinoma; the suspicion was later confirmed by pathologic examination after the tumor had been excised, and his problems disappeared. After six years, a follow-up examination showed that his condition was still stable.

Low levels of thyroid hormone in the absence of clinical hypothyroidism often happen to patients with critical non-thyroidal illnesses (NTI). Low thyroid hormone concentrations in serum do not necessarily mean hypofunction of the thyroid gland; rather it is a helpful adaptation of the human body to the underlying diseases. We collected 133 hospitalized cases of critical NTI and analyzed the incidence of this phenomenon. Fifty-three per cent of the patients had T3 level lower than 60 ng/dl (normal:85-165 ng/dl) and 60% had T4 level lower than 6 ug/dl (normal:6-12 ug/dl). The lowest levels were observed in patients who had sepsis, were aged over 70 or died in this admission. Free T4 and TSH levels were within normal range in most cases. There is a strong negative correlation between the prognosis and the level of T4 in these patients. Those patients with markedly low levels of T3 and T4 should be treated more sophisticatedly.

It is very important to find suitable reaction conditions to attain a high specific binding (specific/total binding) in the receptor binding study. Membrane homogenates of pig choroid plexus are known to have exclusively serotonin (5-hydroxytryptamine, 5-HT) receptor of the subtype 5-HT1c. In this study, we used the membrane preparation of pig choroid plexus tissue and the specific binding of [3H]5-HT was 72-84% to serotonin receptor subtype 5-HT1c, as defined by the inhibition of 1 uM 5-HT, when a radioligand concentration of 0.5 nM of [3H]5-HT was used in the assay. Analysis of the properties of specific [3H]5-HT binding in pig choroid plexus tissue membrane preparation revealed linear Scatchard plots. In Tris-HCl buffer without CaCl2, pargyline or ascorbic acid, high average of affinity dissociation constant (Kd) of 1.3 +/- 0.2 nM (SEM, n = 4) and also a high average of receptor density (Bmax) of 284 +/- 12 fmol/mg of protein were found. Pig choroid plexus proves to be a good material for 5-HT1c receptor binding study.

The concept of metrisable Lie algebras was introduced in a previous paper, where some fundamental properties of metrisable Lie algebras have been given. It was shown that, associated with an admissible metric tensor of a metrisable Lie algebra, there is a unique antisymmetric tensor of the third order. A complete solution of the converse problem will be given in this paper; it is first reducedto the solution of a system of algebraic equations and then it is proved that, there always exists a unique metrisable Lie algebra corresponding to each symmetricsolution of the system, even when the solution is trivial. The Lie algebra thus obtained is a reduced metrisable Lie algebra.

A Lie group is said to be metrisable if it admits a Riemannian metric which is invariant under all translations of the group. It is shown that the study of such groups reduces to the study of what are called metrisable Lie algebras, and some necessary conditions for a Lie algebra to be metrisable are given. Various decomposition and existence theorems are also given, and it is shown that every metrisable algebra is the product of an abelian algebra and a number of non-decomposable reduced algebras. The number of independent metrics admitted by a metrisable algebra is examined, and it is shown that the metric is unique when and only when the complex extension of the algebra is simple.

Die Alkyl-Gruppen in den sechsfachkoordinierten Dialkyl-Fe-Komplexen (I) unterliegen einer intramolekularen, reduktiven Kupplung zu den Alkanen (II), induziert durch die Zersetzung der Komplexe (I) mit Einaquivalent-Oxidantien wie Na-hexachloroiridat(IV), Brz, C12, I2, ICI, Tl(III)-, Ce(IV)-tri- fluoracetat oder Co(III)-acetat.

Die Alkyl-Gruppen in den sechsfachkoordinierten Dialkyl-Fe-Komplexen (I) unterliegen einer intramolekularen, reduktiven Kupplung zu den Alkanen (II), induziert durch die Zersetzung der Komplexe (I) mit Einaquivalent-Oxidantien wie Na-hexachloroiridat(IV), Brz, C12, I2, ICI, Tl(III)-, Ce(IV)-tri- fluoracetat oder Co(III)-acetat.