Optimum fabrication parameters for preparing high performance SERS substrates based on Si pyramid structure and silver nanoparticles

In this work, we propose simple and inexpensive methods to prepare micro/nano hierarchical Surface-Enhanced Raman Scattering (SERS) substrates, in which pyramid structure is created by using anisotropic wet etching of a silicon wafer and a silver thin film is deposited on these pyramid arrays by thermal evaporation. The ensemble is then annealed at 450 °C for 2 hours to form silver nanoparticles (AgNPs). The sizes and density of the pyramids and AgNPs are optimized mainly by changing the etching temperature (60–80 °C), the thickness of the Ag-film (15–45 nm) and etching time (3–10 min). The ultraviolet visible (UV-Vis) absorbance spectra show that the AgNPs formed with the 30 nm-thick film exhibit the strongest plasmonic effect. Under these conditions, the spherical AgNPs with sizes of 42–48 nm are densely distributed on the silicon micro-pyramid array. The obtained SERS signal is the strongest at the pyramid base-edge size of 7–10 μm. The enhancement factor obtained from the abamectin probe molecules is as high as 1 × 10⁶ and the SERS substrates enable the detection of abamectin concentrations as low as 5.7 × 10⁻⁹ M. Therefore, this work provides a novel SERS substrate structure that has a high potential for use in medicine and biotechnology or as a food security sensor.

AgNPs@PSi substrate can detect abamectin molecules at concentrations as low as 5.7 × 10⁻⁹ M, with an enhancement factor of 1 × 10⁶. Such a remarkable SERS substrate promises great potential for practical applications in food security.     

立体定向技术建立大鼠颞叶癫痫模型

目的 探讨立体定向技术在建立大鼠颞叶癫痫模型的实用性及模型长久癫痫敏感性的病理学基础。方法 按公斤体重计算的红藻氨酸剂量，应用立体定向手术一次性注入大鼠的海马组织，于手术后不同的时间段观察大鼠的癫痫发作情况和海马组织的形态学变化。结果 手术后的大鼠在经历“湿狗样抖动”、口唇和头的自运动症、前肢抽搐、后肢抽搐后，进入强直一阵挛性全身发作。以后，每周均有自行发作，发作表现与人类颞叶癫痫发作基本一致。海马神经元的缺失、胶质细胞增生是模型长期癫痫敏感性的基础。结论 立体定向手术建立的大鼠颞叶癫痫模型发作形式、病理学基础与人类的颞叶癫痫基本一致，并且具有长期的癫痫敏感性。同时，应用立体定向技术局部注药，用药量较系统给药明显减少，耗资大大降低，是临床科研中既可靠又经济实用的方法。     

Synthesis of a 2D Cu@TiO2 composite via the design of a 1D Cu-based coordination polymer precursor for efficient and selective photodegradation of dyes

A 2D Cu@TiO₂ composite with a porous and crystalline structure was successfully synthesized via one-step and low-temperature calcination of a 1D Cu-based coordination polymer (Cu-CP), namely [Cu₂(3-dpha)(1,4-NDC)₂(H₂O)₃]_n (3-dpha = N,N′-bis(3-pyridyl)adipamide and 1,4-H₂NDC = 1,4-naphthalenedicarboxylic acid). Moreover, the Cu@TiO₂ membrane was fabricated by a simple filtration of the as-grown Cu@TiO₂ composite. Compared with the benchmark TiO₂ photocatalyst, the Cu@TiO₂ composite material with high specific surface area and reduced photogenerated electron–hole ratio exhibited good photodegradation activity and durability for gentian violet (GV), which could be attributed to the combined effect of co-doping of Cu and TiO₂ structure. Furthermore, the ˙OH and ˙O₂⁻ radicals were predicted to dominate the photocatalytic process. Therefore, this new efficient photocatalyst is a promising candidate for efficient and selective photodegradation of organic pollutants.

A 2D Cu@TiO₂ composite was synthesized via low-temperature calcination of a 1D Cu-CP. Moreover, the Cu@TiO₂ membrane was fabricated by a simple filtration of the Cu@TiO₂ composite which exhibited selective photodegradation activity for GV.     

Isolation method of Saccharomyces cerevisiae from red blood cells based on the optically induced dielectrophoresis technique for the rapid detection of fungal infections

Saccharomyces cerevisiae (S. cerevisiae) has been classically used to treat diarrhea and diarrhea-related diseases. However, in the past two decades, fungal infections caused by S. cerevisiae have been increasing among immunocompromised patients, and it takes too long to isolate S. cerevisiae from blood to diagnose it in time. In this paper, a new method for the isolation and selection of S. cerevisiae from red blood cells (RBC) is proposed by designing a microfluidic chip with an optically-induced dielectrophoresis (ODEP) system. It was verified by theory and experiments that the magnitude and direction of the dielectrophoresis force applied on RBCs and S. cerevisiae are different, which determine that the S. cerevisiae can be isolated from RBCs by the ODEP system. By designing the specific light images and the dynamic separation mode, the optimal operating conditions were experimentally achieved for acquiring higher purity of S. cerevisiae. The purity ranges were up to 95.9%–97.3%. This work demonstrates a promising tool for efficient and effective purification of S. cerevisiae from RBCs and provides a novel method of S. cerevisiae isolation for the timely diagnosis of fungal infections.     

原发性肾病综合征病理类型与三联疗法疗效的关系

本文报告原发性肾病综合征50例,Ⅰ型40例,Ⅱ型10例。全部病例均经肾活检确定病理类型,其中系膜增殖性肾炎17例(34％),膜增殖性肾炎12例(24％),毛细血管内膜增殖性肾炎9例(18％),膜性肾病及微小病变性肾病各3例(6％),局灶硬化性肾炎6例(12％)。经“三联疗法”治疗4～6周后,蛋白尿消失者22例,显效率44％,总有效率达94％。除局灶硬化性肾炎外,其余各类型肾炎均取得显著疗效。可能与各类型肾脏疾病免疫损伤程度有关。     

简介美国肝移植护理新角色—临床护理协调员

自1963年Starzl完成了第1例人体原位肝脏移植以来,肝脏移植在全球范围内得到迅猛发展,并正在以每年10,000例的速度增长。成功的移植不仅帮助那些危重患者重新获得新生,而且对于护理领域也产生了直接深远的影响。由此产生了新型的护理角色———临床护理协调员(Clinic Nursing C