230 research outputs found
Highly Isotactic Poly(N-butenyl-carbazole): Synthesis, Characterization, and Optical Properties
The synthesis of isotactic poly(N-butenyl-carbazole) (i-PBK) by using homogeneous isospecific Ziegler-Natta catalytic system is reported. The achieved polymer is crystalline and shows, to DSC and X-ray analysis, two distinct crystalline phases.i-PBK FTIR spectrum and X-ray diffraction pattern are compared with those of poly(N-vinylcarbazole) (PVK). The observed differences are tentatively associated with higher flexibility of thei-PBK chains due to the alkylene group connecting the carbazole group to the main chain.i-PBK optical properties are also compared with those of PVK and isotactic poly(N-pentenyl-carbazole) (i-PPK), a higher homologue ofi-PBK recently used as emitting layer in organic light emitting diodes (OLEDs) showing white light emission. The close similarity of the fluorescence spectra ofi-PBK andi-PPK is a promising basis for optical applications of this polymer
RF-powered UHF-RFID analog sensors platform
An RF powered UHF-RFID passive sensors platform was realized using discrete components and printed
antennas designed to resonate at 868 MHz, used both for energy harvesting and data transmission. The tests demonstrate the possibility for the system to operate autonomously within the reading range of a standard RFID reader, that acts both as the RF power source and the receiver of the data stored in the tag
user memory. The microcontroller can be interfaced on the same substrate with a sensor made of polymeric materials, sensible to physical parameters or chemical agents.
RF-powered UHF-RFID analog sensors platform (PDF Download Available). Available from: http://www.researchgate.net/publication/279193365_RF-powered_UHF-RFID_analog_sensors_platform [accessed Sep 14, 2015]
Surgical vls therapy of oesophageal achalasia in pediatric age: four case reports
The Authors present a retrospective review of their record of cases, characterized by 4 cases of achalasia in which it was performed a Heller myotomy with front fundoplication (Thall) in laparoscopic approach in the period from 2012 to 2019.
In paediatric achalasia, the laparoscopic Heller myotomy seems to be the best treatment because of its multiple advantages offered by the minimally invasive technique. First of all, thanks to the video-technique, which allows a complete and extended myotomy, the accuracy of this operation is maximized; moreover, the post-operative pain is widely reduced, thanks to the minimal dissection and traction of the tissues; finally, but not negligible, this approach ensures a better aesthetic result than the classic open technique. With regard to the front fundoplication, the Authors suggest that it is mandatory because, even if it extends the operating time, it ensures a natural protection to the myotomy herniated mucosa and avoids gastro-oesophageal reflux, which often occurs after the surgical correction, thus obliging to perform a reoperation
Papillary thyroid carcinoma in paediatric age
In children, differentiated thyroid
carcinoma is a rare condition. Early diagnosis is not
always easy, because of the lack of clinical symptoms,
but it has a pivotal role in performing a correct
therapeutic process.
The study describes three cases of papillary
thyroid carcinoma. None of the three patients had a
positive familiarity or exposure to risk factors. In two
cases, the tumor occurred as a non-injurious swelling in
the anterior cervical region, in the other case it
occurred with a latero-cervical lymphadenopathy that
had been persistent for a year. In the first two patients
we made a certain diagnosis by the needle aspiration of
the thyroid nodule; in the other case the diagnosis was
made by surgical exeresis and histological analysis of
the lymph nodes. We also performed blood chemistry
and hormonal tests, neck ultrasound, chest x-ray.
The three children underwent total
thyroidectomy and two of them also underwent rightsided cervical lymph node exeresis because there was
the presence of metastasis.
In our experience, the best therapeutic strategy
for children with differentiated thyroid carcinoma is the
total thyroidectomy, followed or not by latero-cervical
lymph node exeresis and radioiodiotherapy. The
removal of the whole gland reduces the risk of relapse
Complications of the “nuss procedure” in pectus excavatum
During the pediatric age range, one
the most frequent deformities of the chest wall are
Pectus Excavatum (PE). Currently the treatment of
choice for PE is surgical intervention following the
Nuss procedure.
In this study, we present a description of the
complications associated with surgical treatment of PE
with the Nuss technique, in patients with symmetrical or
asymmetrical deformity, in different stages of disease
severity.
The study was conducted in collaboration with
the Pediatric Hospital “Istituto G. Gaslini” of Genoa.
We analyzed a cohort of 402 patients (334 males and 68
females), who underwent corrective surgery between
2005 and 2018. Within this group of patients, we
observed 82 cases with complications (20.39%), 20 of
which were intraoperative (4.98%) and 62 postoperative (15.42%). For the evaluation of
complications, this group was arbitrarily divided into
patients with symmetric and asymmetric Pectus and in
patients with mild, moderate and severe Pectus using
Haller's index.
Although a small group of patients presented
complications, overall results from data analysis show
that the Nuss technique represents the preferred surgical
procedure for the treatment of PE, in agreement with
literature. Furthermore, in our results show no
correlation between asymmetry or severity of PE with
complication related to the surgery
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