1,871 research outputs found
Shape Memory Polymers for Smart Textile Applications
Shape memory polymer (SMP) is a genre of smart materials which demonstrate a capability to fix in the temporarily programed shape and to recover the original shape upon exposure to external stimuli. Such unique and amazing properties of SMPs are applied to develop smart textiles by incorporating SMP into the fabric. Various types of stimuli-responsive SMPs such as thermal, light, pH, and moisture have been used in textiles for enhancing or attaining some smart properties. The integration of SMPs in fabric provides many fascinating and improved properties such as good aesthetic appeal, comfort, textile soft display, smart controlled drug release, fantasy design, wound monitoring, smart wetting properties and protection against extreme variations in environmental conditions. In this chapter, we discussed different types of SMP used for this purpose, their functions, and applications in textiles with their potential applications in the near future
Krukenberg tumor
Krukenberg tumor is a rare form of metastatic ovarian cancer which accounts for less than 2% of all ovarian tumor. Krukenberg tumor mostly occurs after the age of 40 years and is rarely found in younger age group. It usually presents with bilateral involvement of ovaries. It presents when the primary is already advanced. Here we are presenting a rare case of Krukenberg tumor in a 22 years old female with primary from stomach
Polyurethane: A Shape Memory Polymer (SMP)
Shape memory polymer (SMP) is a stimuli-responsive material with the ability to alter a programmed shape to its original shape upon triggering of an appropriate stimulus. For the past decades, SMP has dragged much interest in material field owing to its various and versatile applications. One archetypal SMP is polyurethane, which has a wide-ranging transition temperature for its shape recovery, retraction temperatures, inherent soft-hard segments, a high recoverable strain (up to 400%), high control of the softening, favorable and tunable physical properties, and so on. This chapter emphasizes on the raw materials required for the synthesis of shape memory polyurethane (SMPU), the principle of shape memory function, the design of protocol of SMPU, and their applications with future directions
Huge fibroid uterus mimicking an ovarian malignancy
Leiomyoma of the uterus is the most common benign tumor arising from uterine smooth muscle. This is a case of a woman with an exophytic uterine leiomyoma mimicking an ovarian neoplasm. The potential for uterine leiomyomas to grow to an extreme size before causing symptoms is quite remarkable. This is likely due to the relatively large volume of the abdominal cavity, the distensibility of the abdominal wall and the slow growth rate of these tumors. In our case report, despite a fibroid of size reaching up to 34 weeks of gestation, our patient had minimal symptoms except for abdominal discomfort. There were no symptoms related to abnormal uterine bleeding or abnormal bowel or bladder habit. Also, the history and clinical examination of the patient favored a diagnosis of ovarian malignancy
Giant uterine cervical polyp: a case report
Cervical polyps are benign growths, usually protruding from the surface of the cervical canal. Two out of three women with cervical polyps present asymptomatically. However, symptomatic women usually present with abnormal uterine bleeding, such as heavy menstrual bleeding, intermenstrual bleeding, or postmenopausal bleeding, as well as vaginal discharge. Giant cervical polyps often are misdiagnosed as malignant in view of their appearance, however most of them are benign in nature. They are also confused with uterine prolapse and uterine inversion. Proper evaluation and diagnosis should be provided so as to ensure complete care to the individual and adequate management
A tough, smart elastomeric bio-based hyperbranched polyurethane nanocomposite
Herein, we fabricate an elastomeric nanocomposite using castor oil-based hyperbranched polyurethane (HPU) and iron oxide nanoparticles decorated reduced graphene oxide (IO-RGO) nanohybrid by an in situ polymerization technique. The designed nanocomposite not only exhibits good thermal properties but also possesses excellent mechanical properties such as tensile strength (24.15 MPa), tensile modulus (28.55 MPa) and toughness (110.8 MJ m À3 ). In addition, the nanocomposite demonstrates rapid and repeatable self-healing abilities under exposure of 20-30 s microwave power input (180-360 W) and by direct sunlight exposure (10 5 lux) for 5-7.5 min. It also demonstrates excellent shape-recovery ability under microwave power (30-60 s) as well as in direct sunlight (1-2.5 min). Thus, the studied tough polymeric material has potential advanced applications
Shape Memory Polyurethane-Based Smart Polymer Substrates for Physiologically Responsive, Dynamic Pressure (Re)Distribution.
Shape memory polymers (SMPs) are an exciting class of stimuli-responsive smart materials that demonstrate reactive and reversible changes in mechanical property, usually by switching between different states due to external stimuli. We report on the development of a polyurethane-based SMP foam for effective pressure redistribution that demonstrates controllable changes in dynamic pressure redistribution capability at a low transition temperature (∼24 °C)-ideally suited to matching modulations in body contact pressure for dynamic pressure relief (e.g., for alleviation or pressure ulcer effects). The resultant SMP material has been extensively characterized by a series of tests including stress-strain testing, compression testing, dynamic mechanical analysis, optical microscopy, UV-visible absorbance spectroscopy, variable-temperature areal pressure distribution, Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, differential scanning calorimetry, dynamic thermogravimetric analysis, and 1H nuclear magnetic resonance spectroscopy. The foam system exhibits high responsivity when tested for plantar pressure modulation with significant potential in pressure ulcers treatment. Efficient pressure redistribution (∼80% reduction in interface pressure), high stress response (∼30% applied stress is stored in fixity and released on recovery), and excellent deformation recovery (∼100%) are demonstrated in addition to significant cycling ability without performance loss. By providing highly effective pressure redistribution and modulation when in contact with the body's surface, this SMP foam offers novel mechanisms for alleviating the risk of pressure ulcers
Comparative study of effectiveness of Papanicolaou smear and visual inspection using acetic acid and visual inspection using Lugol’s iodine for screening of premalignant and malignant lesions of cervix
Background: In developing and resource-limited countries alternative screening methods like VIA, VILI, and Pap smear are used in detection of premalignant and malignant lesions of cervix. The aim of our study was to compare the efficacies of VIA, VILI, and Pap smear in detection of premalignant and malignant lesions of cervix.Methods: The study was conducted for a period of one year in the department of obstetrics and gynaecology, Dr. Rajendra Prasad Government Medical College, Kangra at Tanda, Himachal Pradesh. Women who attended the outdoor patient department of obstetrics and gynecology were subjected to collection of Pap Smear, VIA followed by VILI and a thorough pelvic examination.Results: Among the 350 women studied, 59 women (16.9%) had abnormal VIA, 64 women (18.2%) had abnormal VILI. On pap smear, 10 women were reported as ASCUS, 11 as L-SIL and 1 as H-SIL. Cervical biopsy was done in 98 women, out of which 70 had one or more abnormality on VIA, VILI, or Pap, and 28 women who had normal results. Sixteen women (16.3%) reported as CIN-1 and 2 women (2.07%) as CIN-3. VIA and VILI had a higher sensitivity as compared to pap. However, pap was more specific. The PPV of pap was also much higher as compared to VIA and VILI, whereas there was no difference in NPV of the three.Conclusions: Authors observed that VIA presented the best sensitivity (88.8%), followed by VILI (83.3%), and Pap (72.2%). Pap smear had the highest specificity of 97.2%. The positive predictive value of Pap was higher as compared to VIA and VILI, whereas there was no difference in NPV of the three. VIA and VILI have good sensitivity, with reasonable specificity and because of their cost effectiveness and ease of availability, these can be an alternative screening modality for cervical cancer screening
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