Temperature Measurement by Sublimation Rate as a Process Analytical Technology Tool in Lyophilization

Product temperature (T_b) and drying time constitute critical material attributes and process parameters in the lyophilization process and especially during the primary drying stage. In the study, we performed a temperature measurement by the sublimation rate (TMbySR) to monitor the T_b value and determine the end point of primary drying. First, the water vapor transfer resistance coefficient through the main pipe from the chamber to the condenser (C_r) was estimated via the water sublimation test. The use of C_r value made it possible to obtain the time course of T_b from the measurement of pressure at the drying chamber and at the condenser. Second, a Flomoxef sodium bulk solution was lyophilized by using the TMbySR system. The outcome was satisfactory when compared with that obtained via conventional sensors. The same was applicable for the determination of the end point of primary drying. A laboratory-scale application of the TMbySR system was evidenced via the experiment using 220-, 440-, and 660-vial scales of lyophilization. The outcome was not dependent on the loading amount. Thus, the results confirmed that the TMbySR system is a promising tool in laboratory scale.     

Utilidad de las curas locales tras dacriocistorrinostomía láser

Introduction and objectivesEpiphora caused by nasolacrimal drainage system obstruction is the main indication for dacryocystorhinostomy (DCR). So are chronic conjunctivitis and dacryocystitis from the same origin. Nasal endoscopy and the introduction of laser assisted DCR have facilitated the performance of the technique. However, it requires complex and expensive equipment, so there are still supporters of the traditional external procedure.The aim of this work was to study the effectiveness and usefulness of local postoperative care in laser DCR final result.Material and methodsWe studied a group of 96 patients diagnosed with epiphora secondary to stenosis-occlusion of the nasolacrimal duct. Of these, 32 patients underwent surgery in both eyes, making a total of 128 cases. The surgery was performed in a private setting between January 1999 and December 2008. The 128 cases were divided into 2 groups: 59 cases in which between 4 and 6 postoperative cures were given in the 2 months following the surgery, and another group of 69 cases in which a single cure was given approximately 7 days after surgery. The final assessment of the outcome of the intervention was done in all cases between 24-30 months after surgery.ResultsIn 27 cases out of 128 (79% success), there was a restenosis of tear drainage. No statistically significant differences were found between the 2 groups.ConclusionsIn the sample of patients that were intervened using laser assisted DCR, implementation of postoperative cure was irrelevant in the success of the intervention.     

Laser‐assisted diagnosis of symptomatic cracks in teeth with cracked tooth: A 4‐year in‐vivo follow‐up study

The purpose of this study was to determine whether a near‐infrared diode laser could be used as an adjunct to help identify and localise symptomatic cracks in patients with cracked tooth. An 810‐nm diode laser at 1 W continuous wave energy with a 200 micro‐fibre tip was used to scan the offending tooth. Crack identified during the laser scan was removed, restored and reviewed after four weeks and after 4 years. The laser was able to significantly (P = 0.0001) identify suspected cracked teeth from non‐cracked control teeth. Of the twelve patients examined, ten participants experienced discomfort as the laser passed over a crack line. At 4‐week and 4‐year recall, a majority of the ten treated patients responded positively to the management of crack. This study showed that diode laser could be an adjunctive tool for early detection and management of symptomatic cracks with the possibility of improving long‐term survival.     

半导体激光联合5-氟尿嘧啶治疗牙龈瘤疗效分析

目的　探讨半导体激光联合5-氟尿嘧啶治疗牙龈瘤的临床疗效。 方法    选择2017年1月至2018年6月于深圳市人民医院口腔医学中心就诊的牙龈瘤患者38例, 随机分为单纯半导体激光手术治疗组（激光组）和半导体激光联合5-氟尿嘧啶治疗组（激光联合5-氟尿嘧啶组）,每组19例。术后随访12个月,比较两组的治愈率和复发情况。结果　激光联合5-氟尿嘧啶组治愈19例,治愈率为100%;激光组治愈15例,复发4例,治愈率为78.9%;两组治愈率差异有统计学意义（P = 0.035）。38例患者术后病理结果：血管型26例,纤维型8例,肉芽肿型 4例。结论　牙龈瘤具有复发倾向,应用半导体激光照射联合5-氟尿嘧啶局部注射,治疗效果好且可明显降低复发率,值得临床推广。     

Effect of Agitation of EDTA with 808-Nanometer Diode Laser on Removal of Smear Layer

Introduction

Near-infrared diode lasers can be used for several applications, which range from disinfection to smear layer removal in endodontics. This study evaluated the efficacy of agitation of 15% EDTA with an 808-nm diode laser on removal of the smear layer.

Methods

Sixty extracted human maxillary central incisor teeth were instrumented up to ProTaper F4 (Dentsply Maillefer, Ballagues, Switzerland) and then randomly divided into 6 groups (n = 10 for each group) according to the different final irrigating protocols as follows: 5% sodium hypochlorite for 120 seconds performed with the NaviTip (Dentsply Maillefer, Ballaigues, Switzerland) (control group); 15% EDTA for 120 seconds performed with the NaviTip; and agitation of 15% EDTA with an 808-nm diode laser for 10, 20, 30, and 40 seconds. Specimens were observed under a scanning electron microscope, and open dentinal tubules were counted using Adobe Photoshop software (Adobe Systems, San Jose, CA). The data were analyzed with 1-way analysis of variance and Tukey post hoc tests (P = .05).

Results

The number of open dentinal tubules was higher in the middle thirds than in the apical thirds. The differences between the apical and middle thirds were statistically significant (P < .05). Statistically significant differences were also found between the control group and the other groups in both the middle and apical thirds of the root canals (P < .05).

Conclusions

The results indicated that agitation of 15% EDTA with an 808-nm diode laser for 20 seconds was effective in removing the smear layer in the apical thirds of root canals.     

577nm阈值下微脉冲激光与传统激光治疗DME疗效的系统评价

目的：系统评价577nm阈值下微脉冲激光与传统激光治疗糖尿病性黄斑水肿(DME)疗效差异性。

方法：计算机检索PubMed、Embase、Cochrane图书馆、Web of Science、CBM、 CNKI、CQVIP、CECDB数据库内的相关前瞻性或回顾性临床对照试验,检索时限均为从建库起截止2019-08。由两位研究者独立筛选文献、提取资料、评价文献质量,采用RevMan5.3/Stata 14.0软件对纳入研究进行meta分析。

结果：纳入7项研究,其中随机对照试验(RCT)6 项,回顾性临床对照研究(CCT)1项,共401例患者545眼。Meta分析结果显示：577nm阈值下微脉冲激光组BCVA的测量值高于传统激光组 \〖95%CI(0.02～0.08),P=0.002\〗,577nm阈值下微脉冲激光组的黄斑中心视网膜厚度测量值较传统激光组明显减少[95% CI(-26.96～-10.88),P<0.00001],577nm阈值下微脉冲激光组黄斑10°范围内视网膜平均光敏感度水平的测量值较传统激光组明显提升[95% CI(1.56～2.39),P<0.00001]。

结论：577nm阈值下微脉冲激光能更好地改善DME患者的视功能,且具有较高的治疗安全性,对于患者的治疗具有较好的研究价值。     

Correlation between Defects and Electrical Performances of Ion-Irradiated 4H-SiC p–n Junctions

In this study, 4H-SiC p–n junctions were irradiated with 700 keV He⁺ ions in the fluence range 1.0 × 10¹² to 1.0 × 10¹⁵ ions/cm². The effects of irradiation were investigated by current–voltage (I–V) and capacitance–voltage (C–V) measurements, while deep-level transient spectroscopy (DLTS) was used to study the traps introduced by irradiation defects. Modifications of the device’s electrical performances were observed after irradiation, and two fluence regimes were identified. In the low fluence range (≤10¹³ ions/cm²), I–V characteristics evidenced an increase in series resistance, which can be associated with the decrease in the dopant concentration, as also denoted by C–V measurements. In addition, the pre-exponential parameter of junction generation current increased with fluence due to the increase in point defect concentration. The main produced defect states were the Z_1/2, RD_1/2, and EH_6/7 centers, whose concentrations increased with fluence. At high fluence (>10¹³ ions/cm²), I–V curves showed a strong decrease in the generation current, while DLTS evidenced a rearrangement of defects. The detailed electrical characterization of the p–n junction performed at different temperatures highlights the existence of conduction paths with peculiar electrical properties introduced by high fluence irradiation. The results suggest the formation of localized highly resistive regions (realized by agglomeration of point defects) in parallel with the main junction.