Teaching scientific creativity through philosophy of science

There is a demand to nurture scientific creativity in science education. This paper proposes that the relevant conceptual infrastructure with which to teach scientific creativity is often already included in philosophy of science courses, even those that do not cover scientific creativity explicitly. More precisely, it is shown how paradigm theory can serve as a framework with which to introduce the differences between combinational, exploratory, and transformational creativity in science. Moreover, the types of components given in Kuhn’s disciplinary matrix are argued to indicate a further subdivision within transformational creativity that makes explicit that this most radical type of creativity that aims to go beyond and thus to transform the current paradigm can take many different directions. More generally, it is argued that there are several synergies between the topic of scientific creativity and paradigm theory that can be utilized in most philosophy of science courses at relative ease. Doing so should promote the understanding of scientific creativity among students, provide another way to signify the relevance of paradigm theory, and more strategically be a way of reinforcing the place of philosophy of science in science education.

MODIFICATIONS OF GEAR WHEEL TEETH OF AVIATION GEARBOXES TO INCREASE THEIR OPERATIONAL RELIABILITY AND TECHNOLOGY

The types and methods of modifications of teeth and gear wheels, which have found application in gearboxes of aircraft and helicopters, are presented. Features of geometry, parameters of different types of initial produced contours, their modifications, application and influence of various factors on improving the operational characteristics of gear drives of aviation gearboxes are considered. Arcuate (short and long) and short linear options for modifying the tooth profiles of aircraft gearboxes are best suited to absorb the errors of spur gears. There was no significant difference in the use of short and long correction for a relative decrease in temperature in the contact zone of the wheel teeth, therefore, the use of any correction of the tooth profile, with rare exceptions, turns out to be useful. The advantages of using increased profile angles in comparison with the standard ones used in general mechanical engineering are considered. Development of designs of teeth and gear wheels in aircraft gearboxes, the use of gears with teeth of an asymmetric profile, which can be considered as a cardinal modification of the tooth profiles. The use of such gears increases the strength of the teeth due to the increase in the thickness of the teeth. Unsymmetrical teeth have a large thickness at the tip, which reduces teeth chipping and due to their greater height, greater smoothness of engagement is achieved, bending and contact stresses are reduced. The most radical type of modification is the use of asymmetric profiles of the teeth of the wheels of aircraft gearboxes.

The role of perioperative ureteral stenting for urologic complications in radical surgery of cervical cancer

Introduction: This study aimed to establish the urologic complications of radical type C2 hysterectomy in cervical cancer patients with or without ureteral stenting. Methods: This prospective randomized study included 76 (100%) patients with clinically and pathologically established cervical cancer stages I and II treated with radical type C2 hysterectomy with pelvic lymph node dissection for the last 5 years (2014–2019). Patients were randomized into two groups (2:1 ratio): group II received perioperative ureteral stenting ( n = 24, 31.6%) and group I did not ( n = 52, 68.4%). Urologic complications observed during follow-up include intraoperative ureter and urinary bladder lesions and postoperative ureterovaginal and vesicovaginal fistulas. Results: Of the 52 patients in group I who underwent surgery for cervical cancer, urologic complications were observed in 8 (10.5%) patients, 2 (2.6%) of whom underwent preoperative radiation therapy. In group II, urologic complications were observed in 2 (2.6%) patients, of which 1 (1.3%) received preoperative radiation therapy. Intraoperative urologic complications in group I (6.6%) included 3 (3.9%) ureteral lesions cases and 2 (2.6%) cases of urinary bladder lesions, wherein 1 patient received preoperative radiation therapy. One case of (1.3%) urinary bladder lesion was observed in group II. Postoperative complications were observed in 3 patients (3.9%) in group I, including 2 (2.6%) ureterovaginal fistula cases, wherein 1 (1.3%) patient received preoperative radiation therapy, and 1 (1.3%) case of vesicovaginal fistula. In group II, 1 (1.3%) patient who received perioperative radiotherapy developed postoperative vesicovaginal fistula. Discussion: Urologic complications are extremely common during and after radical surgery (hysterectomy type C2) for cervical cancer. The cervical cancer stage had a significant effect on intra- and postoperative urologic complication rates in this study; however, no such effect was observed for preoperative radiation therapy and ureteral stenting, and significant differences were observed between the two study groups.

Metal-Free Photocatalytic Hydrosilylation of Olefins in the Presence of Photoinitiator

A convenient metal-free photocatalytic hydrosilylation of variety of linear and cyclic alkenes have been investigated. It was found that the free radical type photoinitiator Irgacure 2959 had a better effect...

Non-symmetric mechanophores prepared from radical-type symmetric mechanophores: bespoke mechanofunctional polymers

Non-symmetric radical-type mechanophores were synthesized by molecular crossing between two radical-type mechanophores toward the design of bespoke mechanofunctional polymers.