压力容器用封头制造质量控制和专业化生产发展方向

中国法规首次对压力容器等特种设备用封头实施制造资格许可和强制的监督检验制度。本文根据法规标准的规定,对压力容器封头制造质量控制和专业化生产发展方向的要求作一系统的综述,以提高压力容器产品的整体质量,确保特种设备安全万无一失。     

Choroidal melanoma: a review and case report

BACKGROUND: Choroidal melanoma is the most common primary intraocular malignancy in adults. The ongoing Collaborative Ocular Melanoma Study (COMS) was designed to provide specific answers for the management of medium and large choroidal melanomas. The present consensus among authorities is that small (< 3 mm thick) suspected choroidal melanomas can be conservatively managed with periodic observation for evidence of growth. CASE REPORT: Dilated fundus examination of a 68-year-old man revealed a pigmented uveal lesion straddling the ora serrata inferiorly at 5:30 in the right eye. It measured 5 mm in diameter with transillumination and 2.89 mm in thickness with B-scan ultrasonography. Questioning a small choroidal melanoma the patient was referred to an ocular oncologist, who confirmed the lesion was suspicious for choroidal melanoma. CONCLUSION: Although there are clinical signs that suggest lesion growth, true growth must be recorded with serial photographs, ultrasound, and transillumination. Active therapy should usually begin once lesion growth is documented.     

Comparison of the cumulative probability of pregnancy after in vitro fertilization-embryo transfer by infertility factor and age

OBJECTIVE: To compare the cumulative probability of pregnancy after multiple IVF cycles by age and cause of infertility. DESIGN: A prospective study was done in which patients were followed from the time they registered for their first IVF cycle until they achieved a clinical pregnancy, withdrew from treatment, or study was terminated. PATIENTS, SETTING, TREATMENTS: Infertile women undergoing IVF-ET at the Cooper Institute for In Vitro Fertilization were enrolled in this study if the luteal phase leuprolide acetate (LA) and hMG controlled ovarian hyperstimulation (COH) regimen was used. MAIN OUTCOME MEASURES: Clinical pregnancy, as determined by a positive beta-hCG level and ultrasonographic confirmation of a gestational sac, and delivery rates based on number of women with live births were compared by infertility factor and age. RESULTS: The 3-month cumulative probability of pregnancy based on life table analysis was 33% in women with tubal factor who were < or = 35 years of age, 25% in women with tubal factor who were > 35 years of age, 30% for women with multiple factors who were < or = 35 years of age, and 14% for women with multiple factors who were > 35 years of age. The rate for the older women with multiple factors was significantly lower than that for the other groups. The delivery rates were lower for the women with multiple factors than for women under 35 with tubal factor only. CONCLUSIONS: There is a significant effect of age and infertility factor on pregnancy and delivery rates. Physicians should consider these factors in evaluating their patients' prospects for success in IVF-ET.     

VSAT-enhanced ISDN: architectures and implementation

The authors discuss the applications of very small aperture terminals (VSATs) to the ISDN. Typical VSAT network architectures include point-to-point interactive, point-to-multipoint broadcast, and interactive star configurations. VSATs and satellite communications have found new applications for integrated network solutions yielding hybrid network architectures that mix terrestrial and satellite segments. These issues and their implications are examined in the context of ISDN. Six hybrid network configurations are described to address various applications. A proof of concept implementation utilizing a hybrid terrestrial/satellite ISDN network was performed. The demonstration showed the feasibility of using hybrid networks as a backup for terrestrial communications as well as for service extension via satellite. The architecture and implementation of this configuration are described     

Intraoral repair of chipped or fractured veneered zirconia crowns and fixed dental prosthesis: clinical guidelines based on literature review

This article aimed to review the susceptibility to chipping, influencing factors, current protocols for intraoral repair and provide the clinicians with guidelines for repairing. Peer-reviewed literature in English published between 01/01/2000 and 30/06/2017 was electronically searched using PubMed and Google Scholar, followed by manual search of the scientific literature. Multiple key words and their combinations (‘Zirconium’, ‘Zirconia’, ‘Intraoral’, ‘Repair’, ‘Chipping’, ‘Fracture’, ‘Bonding’, and ‘Surface treatment’) and different search strategies were employed for sample selection. The initial search resulted in 189 articles, of which 98 were included in this review. The chipping rates of veneered zirconia-based restorations have been reported range between 0 and 44%. Researchers and clinicians were in favor of the intraoral repair of chipped veneered zirconia-based restorations. While various intraoral repair protocols were available based on the severity of chipping, decisions about intraoral repair were based on the clinical situation, availability/accessibility of repair kits, survival/success rate of repairing, and patient concerns. Intraoral repair seems to be a promising option to correct moderate size of chipping, and its success largely depends on the surface treatment methods used for the fractured surfaces. Hydrofluoric acid etching of the veneering porcelain followed by silanization and air-abrasion of the zirconia framework and then MDP priming have been recommended to create durable bonds. This review suggests that intraoral repair of chipped zirconia-based restorations offers a satisfying option for the patient when restoration replacement is not an option. Treatments for the fracture surface are the most important factors influencing the longevity of repaired zirconia-based restorations.     

Primary hyperparathyroidism secondary to parathyroid carcinoma: report of a case

Distinguishing parathyroid carcinoma from benign hyperparathyroidism is often difficult. Clinical features most commonly associated with parathyroid carcinoma, such as palpable cervical mass, markedly higher serum calcium, high parathyroid hormone immunoassay, and evidence of bone disease may not be present. Therefore, intraoperative recognition is essential. We report a case in which the presenting symptoms, physical examination, and laboratory analysis were consistent with benign disease. During surgery, the finding of an enlarged firm gland with surrounding inflammatory reaction altered the approach to include the possibility of parathyroid carcinoma. The gland and surrounding tissue were removed, and pathologic examination led to the diagnosis of carcinoma. At 18-month follow-up, the patient was free from recurrence. Any parathyroid gland with a gray appearance, firm texture, and surrounding inflammatory reaction should be treated as carcinoma. Initial intraoperative recognition offers the best chance for cure, since local recurrences are rarely curable.     

沙里宁之后的匡溪——根植于其日臻完美的现代主义根源的偶像学院

匡溪教育园区位于密执安州布鲁菲尔德山脉中,它们拥有一种近乎圣洁的品质——它是芬兰裔建筑师伊利尔·沙里宁的遗产,1925~1950年,他为这个校园设计了一系列灿烂壮丽而又亲密和谐的建筑。面对一片如此感人至深的基地,建筑顺斯蒂文·霍尔设计沙里宁的科学学院扩建工程时,依据了混沌学的一条重要原则:奇怪吸引子(1)。其隐含的思想是系统——从气候到历史——从不重复,然而却形成各种模式。霍尔将这一原则应用于交通流线组织,创造出既有关联却又清晰的流线,将他的扩建与沙里宁原有的科学中心相连接。但语言恰似流水:奇怪吸引子这一术语是如此地令人回味,当它用来描述这一建筑时,它超越了霍尔的定义。变化因素诸如文脉、工艺、类型学赋予此术语以新的但有关联的意味,丰富了沙里宁和霍尔、历史和现代、手工的和机械制造的,科学和建筑之间的对话。     

Structural enhancement leading to retardation of in vitro digestion of rice dough in the presence of alginate

The effect of alginate with distinct content of guluronate sequences on the structural properties and in vitro digestion of rice dough has been investigated. Materials were engineered to serve as a model system of instant soup-based rice noodles available in the market. Alginate set externally with calcium within the dough matrix reduced cooking loss and soluble starch leakage following boiling of preparations. Small-deformation dynamic-oscillation monitored the structural properties of alginate networks, which were capable of supporting the starch granules in a cohesive composite gel. Scanning electron microscopy afforded tangible evidence of the dramatic effect of the polysaccharide network on the morphology of rice dough. Fourier transform infrared spectroscopy probed at the molecular lever the efficiency of external setting to deliver calcium ions at the vicinity of the carboxyl groups of the alginate chain. It appears that the continuous alginate phase encapsulates starch granules thus retarding in vitro digestion of the rice dough. Results are promising for the development of commercial rice noodles with superior appearance, textural profile and digestibility.     

Instructor reputation: An expectancy relationship involving student ratings and achievement.

Instructor reputation, defined as student expectations of an instructor's teaching ability, was investigated to determine its influence on student ratings and achievement. Two teaching behaviors, instructor expressiveness and lecture content, were combined with reputation in a 2–3 factorial design to assess interaction effects. 198 undergraduates read an introductory statement about an instructor (reputation), viewed a videotape lecture, rated the instructor, and took a test. Results indicate that reputation interacted with expressiveness but not content, in which students rated the positive, high-expressive instructor more favorably than the negative, high-expressive instructor. Results suggest a complex relationship in which reputation interacts with some teaching behaviors and affects some student outcomes. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)