Frequency Characteristics of AEPs in Normal Young Adults and Comparison of Their Response Threshold and Pure Tone Audiometry Threshold.

ABSTRACT: Objective The tests of three types of auditory evoked potentials （AEPs） were performed on normal young adults, to understand the frequency characteristics of different testing methods and the relationship between response threshold and pure tone audiometry threshold of different methods, and to discuss the forensic value of 3 types of AEPs to evaluate hearing function. Methods Twenty normal young adults were selected, their standard pure tone audiometry threshold, short-term pure tone audiometry threshold and the response threshold of 3 types of AEPs （tone burst-auditory brainstem response, 40 Hz auditory event-related potential and slow vertex response） at 0.5 kHz, 1.0 kHz, 2.0 kHz and 4.0 kHz were recorded. The relationship between the response threshold and standard pure tone audiometry threshold, short-term pure tone audiometry threshold of 3 types of AEPs at different frequencies as well as the differences between different types of AEPs were analyzed. Results The short-term pure tone audiometry threshold was higher than the standard pure tone audiometry threshold at each frequency. The response threshold and standard pure tone audiometry threshold of the 3 types of AEPs all had a certain correlation, and the response threshold of the 3 types of AEPs was higher than short-term pure tone audiometry threshold and standard pure tone audiometry threshold at each frequency. The differences in the differences between the response threshold and standard pure tone audiometry threshold of the 3 types of AEPs at different frequencies had statistical significance. Linear regression mathematical models were established to infer the standard pure tone audiometry threshold （hearing level） from response threshold （sound pressure level） of 3 types of AEPs of normal young adults. Conclusion When using response threshold of different types of AEPs to estimate pure tone audiometry threshold, conversion and correction are needed. Combined use of different types of AEPs could improve the accuracy of hearing function evaluation.

Phylogenetic diversity is a better predictor of wetland community resistance to Alternanthera philoxeroides invasion than species richness.

Highly biodiversity communities have been shown to better resist plant invasions through complementarity effects. Species richness (SR) is a widely used biodiversity metric but lacks explanatory power when there are only a few species. Communities with low SR can have a wide variety of phylogenetic diversities (PD), which might allow for a better prediction of invasibility. We assessed the effect of diversity reduction of a wetland community assemblage typical of the Beijing area on biotic resistance to invasion of the exotic weed Alternanthera philoxeroides and compared the reduction in SR and PD in predicting community invasibility. The eight studied resident species performed similarly when grown alone and when grown in eight-species communities together with the invasive A. philoxeroides. Variation partitioning showed that PD contributed more to variation in both A. philoxeroides traits and community indicators than SR. All A. philoxeroides traits and community indicators, except for evenness index, showed a linear relationship with PD. However, only stem length of A. philoxeroides differed between the one- and two-species treatments, and the diversity index of the communities differed between the one- and two-species treatments and between the one- and four-species treatments. Our results showed that in natural or semi-natural wetlands with relatively low SR, PD may be a better predictor of invasibility than SR. When designing management strategies for mitigating A. philoxeroides invasion, deliberately raising PD is expected to be more efficient than simply increasing species number.

Clonal integration facilitates spread of Paspalum paspaloides from terrestrial to cadmium-contaminated aquatic habitats.

Cadmium (Cd) is a hazardous environmental pollutant with high toxicity to plants, which has been detected in many wetlands. Clonal integration (resource translocation) between connected ramets of clonal plants can increase their tolerance to stress. We hypothesised that clonal integration facilitates spread of amphibious clonal plants from terrestrial to Cd-contaminated aquatic habitats. The spread of an amphibious grass Paspalum paspaloides was simulated by growing basal older ramets in uncontaminated soil connected (allowing integration) or not connected (preventing integration) to apical younger ramets of the same fragments in Cd-contaminated water. Cd contamination of apical ramets of P. paspaloides markedly decreased growth and photosynthetic capacity of the apical ramets without connection to the basal ramets, but did not decrease these properties with connection. Cd contamination did not affect growth of the basal ramets without connection to the apical ramets, but Cd contamination of 4 and 12 mg·l-1 significantly increased growth with connection. Consequently, clonal integration increased growth of the apical ramets, basal ramets and whole clones when the apical ramets were grown in Cd-contaminated water of 4 and 12 mg·l-1 . Cd was detected in the basal ramets with connection to the apical ramets, suggesting Cd could be translocated due to clonal integration. Clonal integration, most likely through translocation of photosynthates, can support P. paspaloides to spread from terrestrial to Cd-contaminated aquatic habitats. Amphibious clonal plants with a high ability for clonal integration are particularly useful for re-vegetation of degraded aquatic habitats caused by Cd contamination.

Highly Efficient Domain Walls Injection in Perpendicular Magnetic Anisotropy Nanowire.

Electrical injection of magnetic domain walls in perpendicular magnetic anisotropy nanowire is crucial for data bit writing in domain wall-based magnetic memory and logic devices. Conventionally, the current pulse required to nucleate a domain wall is approximately ~10(12) A/m(2). Here, we demonstrate an energy efficient structure to inject domain walls. Under an applied electric potential, our proposed Π-shaped stripline generates a highly concentrated current distribution. This creates a highly localized magnetic field that quickly initiates the nucleation of a magnetic domain. The formation and motion of the resulting domain walls can then be electrically detected by means of Ta Hall bars across the nanowire. Our measurements show that the Π-shaped stripline can deterministically write a magnetic data bit in 15 ns even with a relatively low current density of 5.34 × 10(11) A/m(2). Micromagnetic simulations reveal the evolution of the domain nucleation - first, by the formation of a pair of magnetic bubbles, then followed by their rapid expansion into a single domain. Finally, we also demonstrate experimentally that our injection geometry can perform bit writing using only about 30% of the electrical energy as compared to a conventional injection line.

Clinical study of 23 pediatric patients with cryptococcosis.

OBJECTIVE: Cryptococcus neoformans is a common opportunistic infection in adults with acquired immunodeficiency syndrome. However, limited data exist for pediatric patients. The aim of this study was to describe the clinical characteristics of cryptococcosis in pediatric patients. PATIENTS AND METHODS: A retrospective study was conducted at West China Second University Hospital, Sichuan University. Data on risk factors, clinical manifestations, diagnosis methods, treatment, and prognosis were evaluated. Clinical characteristics associated with cryptococcal meningitis and disseminated cryptococcosis were compared. RESULTS: Twelve cases of cryptococcal meningitis and 11 cases of disseminated cryptococcosis were identified. Seventeen cases had no underlying disease, but 6 cases had malnutrition. Only 6 cases had a history of exposure to pigeon droppings. No cases had pulmonary cryptococcosis alone. Coughing, pulmonary moist rales, swollen lymph nodes, liver and spleen, and skin rashes were seen only in disseminated cryptococcosis. The prevalence of headache and positive meningeal irritation sign was higher in cryptococcal meningitis than disseminated cryptococcosis. The proportion of increase in eosinophils was higher in disseminated cryptococcosis than cryptococcal meningitis. The primary methods used for diagnosis included cerebrospinal fluid ink staining, cerebrospinal fluid culture, blood culture, and lymph node biopsy. Two patients stopped treatment, and 21 patients received antifungal therapy. The mortality rate was 39.13%. CONCLUSIONS: Cryptococcosis occurs in non-HIV infected and immunocompetent children. Cryptococcosis lacks specific clinical manifestations. Disseminated cryptococcosis commonly occurs in children. Clinicians should consider a diagnosis of disseminated cryptococcosis for children who present with unexplained long-term fever, mild cough, chest imaging inconsistent with clinical symptoms, lymphadenectasis, hepatosplenomegaly, and eosinophilia.

Early increased ficolin-2 concentrations are associated with severity of liver inflammation and efficacy of anti-viral therapy in chronic hepatitis C patients.

Ficolin-2 is a kind of human serum complement lectin with a structure similar to mannan-binding lectin (MBL), and it has been implicated in innate immunity. Recent studies have shown that complement pathway activation may contribute to hepatitis. However, the relationship between ficolin-2 and viral hepatitis remains largely elusive. The aim of this study was to determine the dynamics of ficolin-2 in patients with chronic hepatitis C. Forty nine patients who had not yet received therapy [24 patients with abnormal alanine aminotransferase (ALT) levels (>40 U/L) and 25 patients with normal ALT levels (≤ 40 U/L)], 28 patients with hepatitis C who received therapy for 2 weeks and 16 patients received therapy for a full month or longer were included in the study. A sandwich enzyme-linked immunosorbent assay (ELISA) was used to measure the ficolin-2 concentrations in all serum samples of patients and 42 healthy donors. We found the concentrations of ficolin-2 were significantly higher in chronic hepatitis C patients with abnormal ALT values than in chronic hepatitis C patients with normal ALT values and healthy controls. Ficolin-2 concentrations in chronic hepatitis C patients with abnormal ALT values were positively correlated with ALT levels (P < 0.05). After therapy, the concentrations of ficolin-2 decreased and accompany with ALT and Hepatitis C virus (HCV) RNA levels. Then, we found ficolin-2 concentrations in rapid viral response (RVR) group decreased significantly (P < 0.05), while in non-RVR group, ficolin-2 decreased slightly (P > 0.05). Our findings suggest that early increased ficolin-2 is highly correlated with hepatic inflammation and rapid viral response.

A minor subspace analysis algorithm.

This paper proposes a learning algorithm which extracts adaptively the minor subspace spanned by the eigenvectors corresponding to the smallest eigenvalues of the autocorrelation matrix of an input signal. We show both analytically and by simulation results that the weight vectors provided by the proposed algorithm are guaranteed to converge to the minor subspace of the input signal. For wider applications, we also present the complex valued version of the proposed minor subspace analysis algorithm.