34 research outputs found
Complex refractive index of MgO in the far infrared region from transmission and reflection measurements
No full textTransient endothelial dysfunction induced by sugar-sweetened beverage consumption may be attenuated by a single bout of aerobic exercise
No full textAbstract not availablePia Varsamis, Guillaume Walther, Bianca Share, Frances Taylor, Simon Stewart, Christian Lorenzen, Jordan Loade
Development of a fluidic sensor for the detection of herbicides using thylakoid preparations immobilised on magnetic beads to aid regenerability
No full textFollowing the industrial revolution and advances in chemical science, the
pollution of the environment with trace organic pollutants has been steadily
increasing, which is of concern, due to their effect on the environmental and
human health. Tighter legislation that has been introduced in order to minimise
the release of harmful pollutants has led to the initiation of monitoring
programmes. For example, drinking water suppliers are obliged to
systematically monitor drinking water supplied for human consumption for a
large range of pollutants. The same applies for waste water treatment facilities.
The well-established standard methods of environmental waters analysis
require sampling and transportation of samples to the laboratory for detailed
measurements. Therefore, the timescale from sampling to reporting is not ideal,
as a considerable lag occurs.
There is therefore the potential for the use of in situ methods that overcome this
issue. As these do not currently exist, a need to address this is identified.
Biosensors are sensing devices that rely on a biologically-derived component
as an integral part of their detection mechanism. Biosensors that respond to
pollutants could be used for rapid, low cost, field-based pre-screening of water
samples.
Herbicides are considered to be the most important class of pesticides used in
the E.U. Herbicides can be highly toxic for human and animal health, and
increase in the application of herbicides in agriculture during recent decades
has resulted in immense pollution of both soil and water. About half of the
herbicides used at present in agriculture inhibit the light reactions in
photosynthesis, mostly by targeting the Photosystem II (PSII) complex.
A method of detecting certain classes of herbicides is therefore proposed; the
photosynthesis-inhibiting herbicides act by binding to PS II, a chlorophyll–
protein complex which plays a vital role in photosynthesis, located in the
thylakoid membrane of algae, cyanobacteria and higher plants. The inhibition of
PS II causes a reduced photoinduced production of hydrogen peroxide, which
can be measured by the HRP-mediated luminol chemiluminescence reaction.
The design and development of a fluidic sensor unit for the detection of such
herbicides, based upon their inhibition of the hydrogen peroxide production, will
employ the use of superparamagnetic beads in order to address issues of reuse
and regenerability.
The illumination-dependent production of hydrogen peroxide by isolated
thylakoids, and its inhibition by herbicides in a concentration-dependent
manner, were achieved and measured with the HRP-mediated
chemiluminescence reaction with luminol in a cuvette, batch format, allowing for
the detection of herbicides down to 6.0 x 10-09.The integration of the above reactions has been achieved by designing and
constructing a fluidic unit that combines the herbicide-dependent production and
the detection of hydrogen peroxide in a single fluidic assay by combining all the
individual steps in a compact, portable format, with both HRP and thylakoids
covalently coupled on superparamagnetic beads. This addresses issues of
regenerability, as the beads are introduced, used and discarded following a
measurement, controlled only by magnetic and flow forces. Herbicide detection
was achieved to a lower LOD of 5.5 x 10-10 M. The concept development,
design and construction of the fluidic unit, as well as results of the detection of
herbicides with the batch assay method has been published, in a paper by the
author (Talanta, 2008, vol. 77, no. 1, pp. 42-47),
Considerable progress has therefore been made towards developing a system
that would be suitable for automated, field deployment applications for the
detection of the most frequently used classes of herbicides; the lower LOD
however is not within the stringent legislated maximum permissible limits set for
herbicides measured in water, in European waters.
An immediate step forward would be to achieve the required lower LOD, with
the unit's development into a prototype instrument that can be field deployed
being the further goal
Analysis of the risk of a secondary displacement in conservati- vely treated paediatric distal radius metaphyseal fractures. A multicentric study
No full textObjectives: Distal radius fractures represent one of the most fre-quent injuries in children. The treatment of choice is a closed reduction followed by immobilisation in plaster cast; the immediate recourse to osteosynthesis with Kirschner wires is only reserved for certain cases. The displacement rate reported in the literature is 21-39%. The aim of this study is to retrospectively evaluate the risk factors for a secondary displacement of metaphyseal radius fractures in a paediatric population treated in three different centres. Materials and methods: The initial treatment for all 360 patients examined was a closed reduction under general anaesthesia and im-mobilisation in an above elbow cast for 4 weeks. The pre-operative displacement, residual post-reduction displacement and possible di-splacement at 7 and 14 days of follow-up were all assessed clinically and radiographically. Results: A loss of reduction was reported in 102 cases; 51 under-went an additional reduction procedure - some followed by osteo-synthesis - while in the remaining 51 cases, the loss of reduction was acceptable in relation to the expectation of remodelling. The most statistically significant variable for the occurrence of a secondary displacement is a severe primary displacement. The association with the ulna fracture is not significantly correlated. The quality of the plaster cast is important for maintaining the reduction. There are a few things to consider as indicators for a second procedure: age, time elapsed from moment of fracture, fracture site and the absence of an acceptable reduction. Conclusions: In our experience, a reduction followed by osteo-synthesis with Kirschner wires should be considered the treatment of choice in fractures with a high risk of secondary displacement, namely those with severe initial displacement or unsatisfactory reduction
Spatial palindromes/palindromic spaces: spatial devices in Vitruvius, Mallarmé, Polieri, Perec and Libeskind
No full textThis thesis explores non-linear geometric texts and narratives in literature and architecture and the experience of space that is facilitated by them. The research focuses on the palindrome because it is a non-linear mathematical/geometrical device that is found both in literature and architecture. In language, the palindrome is expressed in the geometrical arrangement of words, letters or concepts in the text or the narrative; and, in architecture, as mirrored symmetries or palindromic proportions, measurements and distributions of elements in drawings and buildings. The primary aim of the thesis is to explore the spatial qualities of palindromes, and the experience of those qualities not only in text but also in architecture. This dissertation thus consists of two parts: the first examines Spatial Palindromes in terms of the spatial structures of selected texts and considers their relation to architecture; and the second examines Palindromic Spaces in terms of the spatial experiences created by and through palindromes in text and architecture. The first part, Spatial Palindromes, constructs an original history of the spatial qualities of palindromes by looking at the theory guiding the use of non-linear devices in texts and architecture. This history moves from the use of palindromes in the work of classical figures and scholars (Orpheus, Pythagoras and Vitruvius), to the Medieval and Renaissance practice of mnemonics (Frances Yates, Mary Carruthers), to early twentieth-century structural linguistics (Ferdinand de Saussure) and the group OuLiPo (Raymond Queneau, Franyois Le Lionnais) and, finally, to late twentieth-century post-structural linguistics (Jean Baudrillard.) The thesis argues that palindromes create spatial experiences both in texts and architecture. For this reason the second part, Palindromic Spaces, studies the nature of spatial experience in the fictions and designs of Stephane Mallarme, Jacques Polieri, Georges Perec, and Daniel Libeskind. According to Baudrillard the poetic space, hidden or revealed by the anagram and palindrome, is where the solid structure of language is "exterminated." This act of extermination, or the poetic space that palindrome reveals in language, opens up perception, memory and recollection to a spatial experience "that incorporates the recession of outcomes ad infinitum;" a self-generated, self-consumed or self-reflective conception of history and space that this thesis aims to explore in architecture
Management of low rectal gastrointestinal stromal tumor with neoadjuvant therapy and transanal excision: a rare case report and review of the literature
No full textChristopher Kosmidis,1,2 Konstantinos Sapalidis,1 Alexandros Tsakalidis,1 Stefanos Atmatzidis,1 Nikolaos Michalopoulos,1 Georgios Koimtzis,1 Georgia Karayannopoulou,3 Sofia Lypiridou,3 Nikolaos Varsamis,2 Georgios Kouklakis,2 Sofia Baka,2 Paul Zarogoulidis,1 Isaac Kesisoglou1 1Third Department of Surgery, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece; 2Department of Oncology, Interbalkan Medical Center, Thessaloniki, Greece; 3Department of Pathology, Aristotle University of Thessaloniki, Thessaloniki, Greece Background: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. However, rectal GISTs represent only 5% of this category. We report a case of a rectal GIST treated with local excision after neoadjuvant therapy. Case presentation: A 41-year-old male patient presented with anal bleeding. Colonoscopy revealed a mass located 5 cm from the anal verge. Histological examination showed a GIST with immunohistochemical positivity for CD117 and CD34. Transanal local excision was performed after neoadjuvant therapy. Conclusion: Neoadjuvant immunotherapy for GISTs with unfavorable localization may facilitate local excision and avoid complications of more demanding operations. Keywords: gastrointestinal stromal tumor, rectal, neoadjuvant therapy, transanal excisio
Primary hepatocellular carcinoma in a patient with history of treated breast cancer: a case report with challenging diagnosis and treatment
No full textChristoforos Kosmidis,1 Nikolaos Varsamis,1 Georgios Anthimidis,1 Sofia Baka,2 Dimitrios Valoukas,3 Triantafyllia Koletsa,4 Katerina Zarampouka,4 Georgios Koimtzis,5 Eleni Georgakoudi,6 Paul Zarogoulidis,7 Christoforos Efthymiadis1 1Department of Surgery, Interbalkan European Medical Center, Thessaloniki, Greece; 2Department of Oncology, Interbalkan European Medical Center, Thessaloniki, Greece; 3Department of Oncology, General Hospital of Ptolemaida, Ptolemaida, Greece; 4Pathology Department, Faculty of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece; 5Third Surgical Department, Faculty of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece; 6Aristotle University of Thessaloniki, Thessaloniki, Greece; 7Pulmonary-Oncology Unit, “Theageneio” Cancer Hospital, Thessaloniki, Greece Introduction: Breast cancer is the most common malignancy in women worldwide. Long-term survivors among patients treated for breast cancer are at a high risk for developing a second primary malignancy. Hepatocellular carcinoma is the most frequent primary hepatic malignancy and should be ruled out in breast cancer patients who are diagnosed with solitary hepatic lesions. False diagnosis may lead to inappropriate oncologic staging and treatment of the disease. Case presentation: We present the case of a 73-year-old female patient who had been treated for invasive ductal breast cancer 7 years ago and was diagnosed with a solid hepatic lesion at segments VI and VII and a small, calcified lesion at the tail of the pancreas on follow-up with an abdominal computed tomography. Oncology council decided that both lesions could be resected after determining whether they were metastatic or second primary malignancies. The patient underwent laparotomy and rapid biopsy which showed primary hepatocellular carcinoma and fibrosis of the pancreas. We performed hepatic segmentectomy (VI–VII) and cholecystectomy, while the pancreatic lesion was left intact. The postoperative course of the patient was uncomplicated and she remains disease free 2 years after the operation without any adjuvant therapy. Conclusion: All hepatic lesions detected in breast cancer patients should be evaluated with open mind and liver biopsy should be performed to get a definitive diagnosis and implement the proper treatment strategy. Keywords: breast cancer, hepatocellular cancer, second primary malignancy, rapid biopsy, microwave tissue coagulato
