bluuebunny/crossref_metadata_2025 huggingface dataset:
Post-radiation extra-cranial aneurysm of internal carotid artery
Authors: Fatic N. , Bulatovic N. , Gajin P. , Aleksic N. , Tanaskovic S. , Babic S. , Radak Dj.
Published: November 2015

A 64-year-old male patient was admitted to Clinic for supra-aortic branches
evaluation and multi-detector computerized tomography (MDCT) angiography.
Five years earlier he had stroke with right-sided weakness while nineteen
years ago he was operated for laryngeal cancer followed by radiation therapy.
Ultrasound of carotid arteries revealed left ICA occlusion and right ICA
aneurysm 18 mm in diameter with parietal thrombosis. MDCT angiography
confirmed these findings with fusiform aneurysm of right ICA. Aneurysm
resection was performed and Dacron tubular graft 6mm placed between common
and internal carotid artery. Postoperative course was uneventful, color
duplex showed regular findings and graft patency.
Effects of mistletoe extract on markers of platelet activation and aggregation
Authors: Srdic-Rajic Tatjana , Konic-Ristic Aleksandra , Tisma-Miletic Nevena , Kardum Nevena , Galun Danijel , Sikimic Jelena , Glibetic Marija , Milicevic Miroslav
Published: November 2015

BACKGROUND: Viscum album preparations are extensively used as complementary
therapy in cancer and are shown to exert antitumor activities which involve
the cytotoxic properties, induction of apoptosis, inhibition of angiogenesis
and several other immunomodulatory mechanisms. AIM: The aim of this study was
to investigate the effects of mistletoe extract on platelet as well as
monocyte functions, as an important factors in immunomodulation of cancers
metastatic potencial and angiogenesis in tumors. METHODS: The effect of
different concentrations of mistletoe extract on agonist-induced platelet
activation markers and their aggregation with leukocytes was examined in the
blood of healthy subjects (n=6) using flow cytometry. Effects on LPS -induced
activation markers was determined in the blood of healthy subjects as well as
on THP-1 cell line using an ELISA essays and flow cytometry. RESULTS:
Mistletoe extract significantly inhibited agonist induced P selectin
expression and platelet-monocytes aggregation. Additionally, mistletoe
extract exerts anti-tumor effect through the stimulation of TNF-? production
in LPS induced monocytes activation. CONCLUSION: Obtained data demonstrate
that mistletoe extract was effective in modulating platelet and monocyte
functions, as a part of pleiotropic anticancer effect.
Morphologic and epidemiologic differences between Asian and European population in aneurismatic disease of abdominal aorta
Authors: Mladenovic Ana
Published: November 2015

Background: In this study, we analyzed epidemiologic characteristics and
morphologic differences between Asian and European population in patients
with abdominal aorta aneurysm (AAA). Method: We conducted concomitant study
in Japan and Europe , in 31 Asian patients (AP) with AAA and 130 control
subjects of the same population, and in 30 European patients with AAA and 126
control subjects (EP). We observed various demographic and anthropologic
parameters. Aortography was performed in all patients at the same type of
CT-scanners using the same examination protocol and postprocessing. For data
analysis, various statistical models were used. Results: There are
statistically significant differences in multiple epidemiologic and
morphologic findings in AAA patients, as well as in comparison with controls
in both groups. This is most distinct in terms of anthropologic
characteristics and number of risk-factors, and in terms of morphologic
findings, in the length of neck of the aneurysm, transverse diameter of
abdominal aorta (AA) and common iliac artery (c.i.a), and volumes of c.i.a.
We obtained paradoxical results considering diabetes mellitus, which
presented itself as a protective factor for AAA. Conclusion:
Demographic-epidemiologic analysis accompanied with morphologic measurements
using modern imaging modalities enables obtaining new information on
pathology of AAA in different races. There are differences in number of
risk-factors, and in terms of morphologic findings, in the length neck, angle
of the aneurysm, transverse diameters of abdominal aorta (AA) and in the
length of common iliac artery (c.i.a), and volume of c.i.a.
Original internal derivation catheter endoprosthesis in patients with inoperable infiltration of distal choledochus and biliary-enteric fistula
Authors: Mladenovic Ana , Adnadjevic Perica
Published: November 2015

Aim: The aim of this study was to present the original idea of intervention
radiology procedure treating ireversible cholestasis with intrahepatic
pneumobilia due to choledoho-enteric fistula in inoperable carcinoma of
pancreatic head, in the only possible way. Material and methods: We treated 3
patients with choledocho-enteric fistula using originally designed biliary
catheter endoprosthesis of 14-16 Fr, made of the distal end of drainage
catheter, which enabled bile derivation with simultaneous treatment of
fistulous channel. In pre- and postprocedural evaluation we used
ultrasonography and computed tomography. Results: In 2 of 3 cases we treated
the fistula successfully while preserving bile derivation. The average
survival time was 7,3 months (5-10). Conclusion: The use of this therapeutic
procedure is reserved for the terminal phase of malignant disease. It is a
paliative procedure and implies previous experience in the use of all
possible percutanous biliary drainage.
Common origin for the innominate and left common carotid arteries: A pattern of human aortic branching epicted on multidetector CT
Authors: Ivanovic Aleksandar , Masulovic Dragan , Stevic Ruza , Filipovic Aleksandar
Published: November 2015

Most anomalies of the aortic arch arise due to the persistence of its parts
that normally disappear, or due to the disapperance of parts that normally
persist. We report a variant of aortic arch branching found on chest
computerized tomography in a 75-year old Serbian man who had recurrent
hemoptysis and an abnormal chest radiograph representing marked widening of
the right superior mediastinum. Computerized tomography revealed a shared
origin of the innominate and left common carotid arteries was found. This
finding excluded tumor or pulmonary embolism as a cause of hemoptysis. The
reason for hempotysis was anticoagulant therapy which patient had been
receiving because of cardiovascula disease. We discuss the relative
literature and underline the clinical impact of such a variation.
Sewing needle in the small omentum after ingestion of unknown date
Authors: Knezevic Miroslav , Djurasic Ljubomir
Published: November 2015

Sewing needle inside of the abdominal cavity after ingestion, is described in
a minority of cases, according to reviewed literature. Swallowed foreign body
is more common in children, persons deprived of their liberty and psychiatric
patients. It frequently passes asymptomatic by elimination from the digestive
tract. The patient J.P. 75 years old from Bar, hospitalized at the department
because of metallic foreign bodie - sewing needle in the abdominal cavity.
X-ray native abdominal, MDCT of the abdomen and EGDS in consultation with
gastroenterologist from Clinical Center in Podgorica, is made outpatient.
After treatment the patient was operated on 19th November, 2013 by the
classic laparotomy and after the expected recovery, without complications
discharged. Foreign body in the omentum can arrive from the digestive tube
migration and penetration through the abdominal wall. In some organs of the
abdominal cavity, such as the liver can come through bloodstream. Perforation
of the GI tract occurs in less than 1% of cases, mainly through the digestive
tube runs without problems in about a week. The migration of a sewing needle
through the stomach can cause a state of emergency abdominal or can go
through asymptomatic. Treatment is traditionally classical laparotomy, while
today there are more works that favor the laparoscopic method. The rarity of
surgical practice that has been treated laparotomy and removing foreign
bodies. Today, more and more works where the extraction of foreign bodies
from the abdominal cavity is made by the laparoscopic method.
Fabrication and characterization of superhydrophobic and superlipophilic silica nanofibers mats with excellent heat resistance
Authors: Gao S. , Watanabe H. , Nakane K. , Zhao K.
Published: November 2015

A kind of silica nanofibers (SNF) mats with superhydrophobicity and
superlipophilicity as well as excellent heat resistance, had been prepared by
modifying of 1, 1, 1, 3, 3, 3-hexamethyldisilazane on electrospun SNF mats.
The effects of heat treatment time on properties of modified SNF mats were
investigated by scanning electron microscopy, nitrogen absorption analysis,
X-ray photoelectron spectroscopy, and contact angle measurement. With high
specific surface area 240.1 m2/g, the optimal modified SNF mat approached
water contact angle (WCA) 153.2? and fuel contact angle (FCA) 0?,
furthermore, even after annealing by 450?C in air for 1h , WCA remained at
135.5? and FCA kept at 3.8?, which opened a new way to improve heat
resistance of fuel-water filter paper.
Ultrasound-induced opening of the blood-brain barrier to enhance temozolomide and irinotecan delivery: an experimental study in rabbits
Authors: Beccaria Kevin , Canney Michael , Goldwirt Lauriane , Fernandez Christine , Piquet Julie , Perier Marie-Cécile , Lafon Cyril , Chapelon Jean-Yves , Carpentier Alexandre
Published: November 2015

OBJECT

The blood-brain barrier (BBB) limits the intracerebral penetration of drugs and brain tumor treatment efficacy. The effect of ultrasound-induced BBB opening on the intracerebral concentration of temozolomide (TMZ) and irinotecan (CPT-11) was assessed.

METHODS

This study was performed using 34 healthy New Zealand rabbits. Half had unilateral BBB opening, and half served as controls. Sonications were performed by pulsing a 1.05-MHz planar ultrasound transducer with a duty cycle of 2.5% and an in situ acoustic pressure level of 0.6 MPa after injection of a microbubble ultrasound contrast agent. Drugs were injected either 5 minutes before (ChemoPreUS) or 15 minutes after (ChemoPostUS) the ultrasound sonication. The plasma and intracerebral concentrations of both drugs were quantified using ultra-performance liquid chromatography.

RESULTS

The mean intracerebral tissue-to-plasma drug concentration ratio in the control hemispheres was 34% for TMZ and 2% for CPT-11. After BBB opening, these values increased by up to 21% for TMZ and up to 178% for CPT-11. Intracerebral concentrations of drugs were enhanced in regions where the BBB was opened compared with the contralateral hemisphere (p < 0.01 and p < 0.0001 for CPT-11, p = 0.02 and p = 0.03 for TMZ, in ChemoPreUS and ChemoPostUS, respectively) and compared with the control group (p < 0.001 and p < 0.0001 for CPT-11, p < 0.01 and p = 0.02 for TMZ, in ChemoPreUS and ChemoPostUS, respectively). The intracerebral distribution of drugs was heterogeneous, depending on the distance from the ultrasound source.

CONCLUSIONS

Ultrasound-induced opening of the BBB significantly enhances the intracerebral concentration of both TMZ and CPT-11 in rabbits.
The feasibility of producing patient-specific acrylic cranioplasty implants with a low-cost 3D printer
Authors: Tan Eddie T. W. , Ling Ji Min , Dinesh Shree Kumar
Published: November 2015

OBJECT

Commercially available, preformed patient-specific cranioplasty implants are anatomically accurate but costly. Acrylic bone cement is a commonly used alternative. However, the manual shaping of the bone cement is difficult and may not lead to a satisfactory implant in some cases. The object of this study was to determine the feasibility of fabricating molds using a commercial low-cost 3D printer for the purpose of producing patient-specific acrylic cranioplasty implants.

METHODS

Using data from a high-resolution brain CT scan of a patient with a calvarial defect posthemicraniectomy, a skull phantom and a mold were generated with computer software and fabricated with the 3D printer using the fused deposition modeling method. The mold was used as a template to shape the acrylic implant, which was formed via a polymerization reaction. The resulting implant was fitted to the skull phantom and the cranial index of symmetry was determined.

RESULTS

The skull phantom and mold were successfully fabricated with the 3D printer. The application of acrylic bone cement to the mold was simple and straightforward. The resulting implant did not require further adjustment or drilling prior to being fitted to the skull phantom. The cranial index of symmetry was 96.2% (the cranial index of symmetry is 100% for a perfectly symmetrical skull).

CONCLUSIONS

This study showed that it is feasible to produce patient-specific acrylic cranioplasty implants with a low-cost 3D printer. Further studies are required to determine applicability in the clinical setting. This promising technique has the potential to bring personalized medicine to more patients around the world.
Intracranial-to-intracranial bypass for posterior inferior cerebellar artery aneurysms: options, technical challenges, and results in 35 patients
Authors: Abla Adib A. , McDougall Cameron M. , Breshears Jonathan D. , Lawton Michael T.
Published: November 2015

OBJECT

Intracranial-to-intracranial (IC-IC) bypasses are alternatives to traditional extracranial-to-intracranial (EC-IC) bypasses to reanastomose parent arteries, reimplant efferent branches, revascularize branches with in situ donor arteries, and reconstruct bifurcations with interposition grafts that are entirely intracranial. These bypasses represent an evolution in bypass surgery from using scalp arteries and remote donor sites toward a more local and reconstructive approach. IC-IC bypass can be utilized preferentially when revascularization is needed in the management of complex aneurysms. Experiences using IC-IC bypass, as applied to posterior inferior cerebellar artery (PICA) aneurysms in 35 patients, were reviewed.

METHODS

Patients with PICA aneurysms and vertebral artery (VA) aneurysms involving the PICA’s origin were identified from a prospectively maintained database of the Vascular Neurosurgery Service, and patients who underwent bypass procedures for PICA revascularization were included.

RESULTS

During a 17-year period in which 129 PICA aneurysms in 125 patients were treated microsurgically, 35 IC-IC bypasses were performed as part of PICA aneurysm management, including in situ p3-p3 PICA-PICA bypass in 11 patients (31%), PICA reimplantation in 9 patients (26%), reanastomosis in 14 patients (40%), and 1 V3 VA-to-PICA bypass with an interposition graft (3%). All aneurysms were completely or nearly completely obliterated, 94% of bypasses were patent, 77% of patients were improved or unchanged after treatment, and good outcomes (modified Rankin Scale ≤ 2) were observed in 76% of patients. Two patients died expectantly. Ischemic complications were limited to 2 patients in whom the bypasses occluded, and permanent lower cranial nerve morbidity was limited to 3 patients and did not compromise independent function in any of the patients.

CONCLUSIONS

PICA aneurysms receive the application of IC-IC bypass better than any other aneurysm, with nearly one-quarter of all PICA aneurysms treated microsurgically at our center requiring bypass without a single EC-IC bypass. The selection of PICA bypass is almost algorithmic: trapped aneurysms at the PICA origin or p1 segment are revascularized with a PICA-PICA bypass, with PICA reimplantation as an alternative; trapped p2 segment aneurysms are reanastomosed, bypassed in situ, or reimplanted; distal p3 segment aneurysms are reanastomosed or revascularized with a PICA-PICA bypass; and aneurysms of the p4 segment that are too distal for PICA-PICA bypass are reanastomosed. Interposition grafts are reserved for when these 3 primary options are unsuitable. A constructive approach that preserves the PICA with direct clipping or replaces flow with a bypass when sacrificed should remain an alternative to deconstructive PICA occlusion and endovascular coiling when complete aneurysm occlusion is unlikely.
Angiographically occult vascular malformation of the intracranial accessory nerve: case report
Authors: Terterov Sergei , McLaughlin Nancy , Vinters Harry , Martin Neil A.
Published: November 2015

Angiographically occult cerebral vascular malformations (AOVMs) are usually found in the supratentorial brain parenchyma. Uncommonly, AOVMs can be found within the cavernous sinus or basal cisterns and can be associated with cranial nerves. AOVMs involving the intracranial segment of the spinal accessory nerve have not been described. A 46-year-old female patient presented with a history of episodic frontal headaches and episodes of nausea and dizziness, as well as gait instability progressing over 6 months prior to evaluation. Imaging revealed a well-circumscribed 3-cm extraaxial T1-weighted isointense and T2-weighted hyperintense contrast-enhancing mass centered in the region of the right lateral cerebellomedullary cistern. The patient underwent resection of the lesion. Although the intraoperative appearance was suggestive of a cavernous malformation, some histological findings were atypical, leading to the final diagnosis of vascular malformation, not otherwise specified. The patient’s postoperative course was uneventful with complete resolution of symptoms. To the authors’ knowledge, this is the first report of an AOVM involving the intracranial portion of the accessory nerve. For any AOVM located within the cerebellomedullary cistern or one suspected of involving a cranial nerve, the authors recommend including immunohistochemistry with primary antibody to neurofilament in the histopathology workup.
Expression of matrix metalloproteinase−2 and −9 in human ligamentum flavum cells treated with tumor necrosis factor−α and interleukin-1β
Authors: Kim Bum-Joon , Hur Junseok W. , Park Jong Soo , Kim Joo Han , Kwon Taek-Hyun , Park Youn-Kwan , Moon Hong Joo
Published: November 2015

OBJECT

An in vitro study was performed to understand the potential roles of matrix metalloproteinase (MMP)-2 and MMP-9 in the elastin degradation of human ligamentum flavum (LF) cells via treatment with tumor necrosis factor-α (TNFα) and interleukin-1β (IL-1β). Previous studies have identified a decreased elastin to collagen ratio in hypertrophic LF. Among the extracellular matrix remodeling endopeptidases, MMP-2 and MMP-9 are known to have elastolytic activity. The hypothesis that activated LF cells exposed to inflammation would secrete MMP-2 and MMP-9, thereby resulting in elastin degradation, was examined.

METHODS

To examine MMP-2 and MMP-9 expression in human LF, cells were isolated and cultured from LF tissues that were obtained during lumbar disc surgery. Isolated LF cells were equally divided into 3 flasks and subcultured. Upon cellular confluency, the LF cells were treated with TNFα, IL-1β, or none (as a control) and incubated for 48 hours. The conditioned media were collected and assayed for MMP-2 and MMP-9 using gelatin zymography and Western blot analysis. The electrophoresis bands were compared on densitometric scans using ImageJ software.

RESULTS

The conditioned media from the isolated human LF cells naturally expressed 72-kD and 92-kD gelatinolytic activities on gelatin zymography. The IL-1β-treated LF cells presented sustained increases in the proenzyme/zymogen forms of MMP−2 and −9 (proMMP-2 and proMMP-9), and activeMMP-9 expression (p = 0.001, 0.022, and 0.036, respectively); the TNFα-treated LF cells showed the most elevated proMMP9 secretion (p = 0.006), as determined by Western blot analyses. ActiveMMP-2 expression was not observed on zymography or the Western blot analysis.

CONCLUSIONS

TNFα and IL-1β promote proMMP-2 and proMMP-9 secretion. IL-1β appears to activate proMMP-9 in human LF cells. Based on these findings, selective MMP-9 blockers or antiinflammatory drugs could be potential treatment options for LF hypertrophy.
Glacier elevation and mass changes over the central Karakoram region estimated from TanDEM-X and SRTM/X-SAR digital elevation models
Authors: Rankl Melanie , Braun Matthias
Published: November 2015

Snow cover and glaciers in the Karakoram region are important freshwater resources for many down-river communities as they provide water for irrigation and hydropower. A better understanding of current glacier changes is hence an important informational baseline. We present glacier elevation changes in the central Karakoram region using TanDEM-X and SRTM/X-SAR DEM differences between 2000 and 2012. We calculated elevation differences for glaciers with advancing and stable termini or surge-type glaciers separately using an inventory from a previous study. Glaciers with stable and advancing termini since the 1970s showed nearly balanced elevation changes of -0.09 ±0.12 m a-1 on average or mass budgets of -0.01 ±0.02Gt a-1 (using a density of 850 kg m-3). Our findings are in accordance with previous studies indicating stable or only slightly negative glacier mass balances during recent years in the Karakoram. The high-resolution elevation changes revealed distinct patterns of mass relocation at glacier surfaces during active surge cycles. The formation of kinematic waves at quiescent surge-type glaciers could be observed and points towards future active surge behaviour. Our study reveals the potential of the TanDEM-X mission to estimate geodetic glacier mass balances, but also points to still existing uncertainties induced by the geodetic method.
Is it Arrogant to Deny Climate Change or is it Arrogant to Say it is Arrogant? Understanding Arrogance and Cultivating Humility in Climate Change Discourse and Education
Authors: Ferkany Matt
Published: November 2015

This paper assesses the charge that climate change denial is arrogant and considers the educational priorities most appropriate to fostering greater humility about the climate change problem. I argue that even denial formed in ignorance of the organised misinformation campaign often constitutes a kind of arrogance, but that it is quite possible to humbly doubt the climate change problem. In some cases denial flows from other more or less serious errors or vices, such as ignorance, sincere but mistaken belief, dishonesty or selfishness. Those who press the arrogance charge also risk being arrogant in doing so. Educators can do a number of things to promote greater humility about climate change, including providing experiences that increase people's appreciation of their individual and general human limitations and improving their ability to distinguish credible from discreditable sources of scientific information and factual from normative dimensions of the climate change problem.
Stability and Change in British Public Discourses about Climate Change between 1997 and 2010
Authors: Capstick Stuart Bryce , Pidgeon Nicholas Frank , Henwood Karen
Published: November 2015

Public understanding of climate change has been a topic of environmental social sciences research since the early 1990s. To date, temporal change in climate change understanding has been approached almost exclusively using quantitative, survey-based methodologies, which indicate that people's responses on a limited number of measures have indeed altered in response to changing circumstances. However, quantitative longitudinal evidence can be criticised for presenting an overly simplistic view of people's beliefs and values. The current study is the first to explore changes in public understanding over an extended time period using in-depth qualitative methods. The study utilises a novel longitudinal methodology to explore changes in discourses across six separate datasets collected over the period 1997-2010, comprising a total of 208 public participants from across Great Britain. We find for the first time that discourses regarding the relevance of climate change to everyday life, and concerning rationales for personal action have exhibited subtle but important shifts over this period. By contrast, other aspects of public understanding have exhibited considerable stability over time, particularly with respect to ethical principles concerning stewardship of nature, justice and fairness. We conclude by distinguishing between three scales of change in public understanding of climate change: relatively short-lived movements in attitudes as revealed by survey data and influenced by transitory phenomena; slower shifts in public discourses that track changing cultural contexts; and enduring ways of understanding climate change that are tied to longer-term ethical foundations.
Impure Procedural Justice in Climate Governance Systems
Authors: Grasso Marco , Sacchi Simona
Published: November 2015

Climate change governance is extremely challenging because of both the intrinsic difficulty of the issues at stake and the plurality of values and world-views. For these reasons, the ethical concerns that characterise climate change should also be meaningfully addressed through a specific version of procedural justice. Accordingly, in this article we adopt an impure notion of procedural justice. On this theoretical basis, we define relevant fairness criteria and contextualise them for climate governance systems. Then, we empirically justify fairness criteria against a critical and divisive element for the future governance of the Green Climate Fund, i.e., the no-objection procedure. The article concludes with some considerations prompted by the analysis.
Managing Climate Change: Shifting Roles for NGOs in the Climate Negotiations
Authors: Pandey Chandra Lal
Published: November 2015

Non-governmental organisations have been playing a significant role in the formation and implementation of global climate change policies. The incremental participation of non-governmental organisations in climate change negotiations is significant for two reasons: 1) they provide governments with expertise and information; and 2) they help to bridge the lack of democracy and legitimacy in global environmental governance. The fulfilment of these two functions, however, is surrounded by doubts, as very little progress has been made so far in combating climate change. Many non-governmental organisations themselves lack democratic legitimacy in their formation and structures, and international climate change agreements are often fragile, not because the negotiators lack information but because they lack political will. This paper examines and outlines the areas for identifying how non-governmental organisations could contribute more to produce effective climate policies, in order to mitigate and manage climate change in the absence of more democratic international climate-change policy-making processes.
La France à l'heure de la mondialisation
Authors: de Wenden Catherine Wihtol
Published: November 2015

Les nationalités étrangères les plus nombreuses en France sont toujours les mêmes qu'il y a trente ans: Portugais, Algériens, Marocains, dans le même ordre d'importance décroissante, suivis ensuite par les Turcs et les Tunisiens. L'Afrique sub-saharienne est plus présente qu'il y a trente ans et de nouvelles nationalités ont fait surface comme les Pakistanais, Afghans et autres originaires du Proche et du Moyen Orient du fait des crises qui ont sévi dans la région depuis ces trente dernières années. Face à ces flux migratoires, la question de l'intégration par les politiques urbaines, le dialogue avec l'Islam dans l'espace public, la lutte contre les discriminations et la définition du vivre ensemble ne cessent de susciter pendant toute cette période d'importants débats.
Débattre sur l'identité nationale: l'immigration et l'intégration en question
Authors: Gastaut Yvan
Published: November 2015

En novembre 2009, le gouvernement présidé par Nicolas Sarkozy lance en fanfare un vaste débat sur l'identité nationale en France. Innovateur dans sa forme – c'est la première fois qu'un gouvernement français décide de son propre chef d'organiser un débat sur ce sujet en invitant l'ensemble de la population nationale à y participer – ce débat s'insère sur le fond dans une longue série de convulsions qui depuis les années 1980 ne cessent d'agiter la sphère publique. Une thématique revient de manière récurrente dans ces débats: celle d'une « invasion » qui menacerait de détruire la nation française. Le déroulement de la consultation lancée en 2009 démontre l'impossibilité de mettre en place sereinement un débat aussi complexe et difficile dans un cadre aussi formaté: libérer la parole, c'est s'exposer à un racisme ordinaire qui a débordé à maintes reprises les promoteurs de ce vaste forum national.
Focus on the Outer Membrane Factor OprM, the Forgotten Player from Efflux Pumps Assemblies
Authors: Phan Gilles , Picard Martin , Broutin Isabelle
Published: November 2015

Antibiotics have been used extensively during several decades and we are now facing the emergence of multidrug resistant strains. It has become a major public concern, urging the need to discover new strategies to combat them. Among the different ways used by bacteria to resist antibiotics, the active efflux is one of the main mechanisms. In Gram-negative bacteria the efflux pumps are comprised of three components forming a long edifice crossing the complete cell wall from the inside to the outside of the cell. Blocking these pumps would permit the restoration of the effectiveness of the current antibiotherapy which is why it is important to increase our knowledge on the different proteins involved in these complexes. A tremendous number of experiments have been performed on the inner membrane protein AcrB from Escherichia coli and, to a lesser extent, the protein partners forming the AcrAB-TolC pump, but less information is available concerning the efflux pumps from other virulent Gram-negative bacteria. The present review will focus on the OprM outer membrane protein from the MexAB-OprM pump of Pseudomonas aeruginosa, highlighting similarities and differences compare to the archetypal AcrAB-TolC in terms of structure, function, and assembly properties.
A New Mechanism for THz Detection Based on the Tunneling Effect in Bi-Layer Graphene Nanoribbons
Authors: Maffucci Antonio
Published: November 2015

A new possible mechanism of signal detection in the THz range is investigated, based on the excitation of resonances due to the tunneling effect between two graphene nanoribbons. A simple detector is proposed, where two graphene nanoribbons are used to contact two copper electrodes. The terminal voltages are shown to exhibit strong resonances when the frequency of an external impinging field is tuned to the characteristic tunneling frequency of the graphene layer pair. An electrodynamic model for the electron transport along the graphene nanoribbons is extended here to include the tunneling effect, and a coupled transmission line model is finally derived. This model is able to predict not only the tunneling resonance, but also the well-known plasmon resonances, related to the propagation of slow surface waves.
Development of a Fractional Order Chaos Synchronization Dynamic Error Detector for Maximum Power Point Tracking of Photovoltaic Power Systems
Authors: Yu Kuo-Nan , Yau Her-Terng , Liao Chi-Kang
Published: November 2015

In recent years, the photovoltaic (PV) power generation system has been widely discussed and researched. Research on electric energy focuses on the development of Maximum Power Point Tracking (MPPT) technology, and many methods have been proposed. However, these studies have a common defect: the tracking continues near the maximum power point (MPP), so that the waveform of output power jitters, thus causing power loss and rapid wearing of electronic modules. In order to remedy this defect, this paper proposes a new type of fractional order chaos synchronization dynamic error detector for the MPPT design of a PV power system. In this study, the Sprott chaos synchronization dynamic error system was used to control the pulse width duty cycle of PWM and optimize the power oscillation of a PV power system during steady-state response. The simulation and experimental results showed that the voltage detector proposed in this paper can reduce the power oscillation of a PV power system during steady-state response, and increase the overall system efficiency. From the steady-state responses of MPPT, it can be seen that about 0.2 vibration amplitude can be suppressed with control action. Therefore, about 4% of steady-state vibration energy can be saved.
Immune Mechanisms Linking Obesity and Preeclampsia
Authors: Spradley Frank , Palei Ana , Granger Joey
Published: November 2015

Preeclampsia (PE) is characterized by hypertension occurring after the twentieth week of pregnancy. It is a significant contributor to maternal and perinatal morbidity and mortality in developing countries and its pervasiveness is increasing within developed countries including the USA. However, the mechanisms mediating the pathogenesis of this maternal disorder and its rising prevalence are far from clear. A major theory with strong experimental evidence is that placental ischemia, resulting from inappropriate remodeling and widening of the maternal spiral arteries, stimulates the release of soluble factors from the ischemic placenta causing maternal endothelial dysfunction and hypertension. Aberrant maternal immune responses and inflammation have been implicated in each of these stages in the cascade leading to PE. Regarding the increased prevalence of this disease, it is becoming increasingly evident from epidemiological data that obesity, which is a state of chronic inflammation in itself, increases the risk for PE. Although the specific mechanisms whereby obesity increases the rate of PE are unclear, there are strong candidates including activated macrophages and natural killer cells within the uterus and placenta and activation in the periphery of T helper cells producing cytokines including TNF-α, IL-6 and IL-17 and the anti-angiogenic factor sFlt-1 and B cells producing the agonistic autoantibodies to the angiotensin type 1 receptor (AT1-aa). This review will focus on the immune mechanisms that have been implicated in the pathogenesis of hypertension in PE with an emphasis on the potential importance of inflammatory factors in the increased risk of developing PE in obese pregnancies.
Direct Conversion of Carbohydrates into Ethyl Levulinate with Potassium Phosphotungstate as an Efficient Catalyst
Authors: Zhao Shiqiang , Xu Guizhuan , Chang Chun , Fang Shuqi , Liu Ze , Du Fengguang
Published: November 2015

A series of metal-modified phosphotungstates were prepared and performed for direct synthesis of ethyl levulinate from fructose in ethanol. Considering the cost of catalysts, catalytic activity of catalysts, and easy separation of catalysts together, K-HPW-1 was chosen as the most suitable catalyst for synthesis of ethyl levulinate from fructose. A high ethyl levulinate yield of 64.6 mol% was obtained at 150 °C within 2 h in ethanol. The introduction of low polar toluene as a co-solvent improved the yield of ethyl levulinate to 68.7 mol%. The recovered catalyst remained high activity with the yield of ethyl levulinate converted from fructose above 50 mol% after being used five times. Moreover, the generality of the catalyst was further demonstrated by glucose, sucrose, inulin, and cellulose with ethyl levulinate yielding 14.5, 35.4, 52.3, and 14.8 mol%, respectively.
Zr-SBA-15 Lewis Acid Catalyst: Activity in Meerwein Ponndorf Verley Reduction
Authors: Iglesias Jose , Melero Juan , Morales Gabriel , Moreno Jovita , Segura Yolanda , Paniagua Marta , Cambra Alberto , Hernández Blanca
Published: November 2015

Zr-SBA-15 Lewis acid catalyst has demonstrated an outstanding catalytic activity in the reduction of several carbonyl compounds by means of Meerwein Ponndorf Verley (MPV) reaction, using several secondary alcohols, and showing a very high selectivity towards the desired products. Special focus was addressed in the catalytic activity of Zr-SBA-15 material in the production of furfuryl alcohol from furfural, which is an important reaction for the lignocellulosic biomass valorization. In this transformation, both the reaction temperature and the i-PrOH:Furfural molar ratio exert a positive influence on the rate of the MPV transformation, with the influence of the former being much higher. i-propyl-furfuryl ether, a by-product resulting from the etherification of the target product with the sacrificing alcohol, is also found together with the main product. The production of this side-product is highly influenced by the reaction temperature, so that low temperatures and high sacrificing alcohol to substrate molar ratios have to be applied to keep its production at low levels.
Natural Deposit Coatings on Steel during Cathodic Protection and Hydrogen Ingress
Authors: Smith Wayne , Paul Shiladitya
Published: November 2015

The calcareous coating formed during cathodic protection (CP) in seawater is known to reduce the current demand by hindering the transport of species required to support the cathodic reactions and, thereby, improve the economic performance of CP systems. There is, however, uncertainty as to whether the coating reduces hydrogen uptake or indeed enhances it. To ascertain this, two sets of samples were polarized at −1.1 V (standard calomel electrode, SCE) in 3.5% w/v NaCl and synthetic seawater (ASTM D1141) at 20 °C and the diffusible hydrogen content measured over a period of 530 h. Under such conditions reports suggest a deposit with two distinct layers, comprising an initial brucite layer followed by an aragonite layer. Contrary to other findings, a fine initial layer containing Ca and Mg followed by a brucite layer was deposited with a few specks of Ca-containing zones in synthetic seawater. The hydrogen uptake was found to occur within the initial 100 h of exposure in synthetic seawater whilst it continued without the benefit of a deposit coating, i.e., in 3.5 wt % NaCl solution.
The Search for Durable Exterior Clear Coatings for Wood
Authors: Evans Philip , Haase Jonathan , Seman A. , Kiguchi Makoto
Published: November 2015

The goal of a durable exterior clear coating has eluded generations of coatings technologists, despite long-standing desire amongst the public for such a coating. The journey towards this goal initially focused on modifications to coating formulation, but took a completely different direction when it was found that a UV-transparent silicone clear coating on wood modified with chromic acid met consumer expectations of coating durability. This finding sparked world-wide interest in wood pre-treatments as a way of enhancing the durability of clear coatings. This interest initially focused on transition metal compounds, but has now shifted in the direction of organic and inorganic photostabilizers or even more drastic pre-treatments. Pre-treatments that dimensionally stabilize wood, protect it from microbial degradation and photostabilize lignin, when combined with flexible, photostable, coatings provide the next way-stop on the journey towards achieving the goal of durable exterior clear coatings for wood. This paper reviews this journey, drawing upon our research and that of other groups who have focused on this elusive goal.
Using Expectation Maximization and Resource Overlap Techniques to Classify Species According to Their Niche Similarities in Mutualistic Networks
Authors: Fort Hugo , Mungan Muhittin
Published: November 2015

Mutualistic networks in nature are widespread and play a key role in generating the diversity of life on Earth. They constitute an interdisciplinary field where physicists, biologists and computer scientists work together. Plant-pollinator mutualisms in particular form complex networks of interdependence between often hundreds of species. Understanding the architecture of these networks is of paramount importance for assessing the robustness of the corresponding communities to global change and management strategies. Advances in this problem are currently limited mainly due to the lack of methodological tools to deal with the intrinsic complexity of mutualisms, as well as the scarcity and incompleteness of available empirical data. One way to uncover the structure underlying complex networks is to employ information theoretical statistical inference methods, such as the expectation maximization (EM) algorithm. In particular, such an approach can be used to cluster the nodes of a network based on the similarity of their node neighborhoods. Here, we show how to connect network theory with the classical ecological niche theory for mutualistic plant-pollinator webs by using the EM algorithm. We apply EM to classify the nodes of an extensive collection of mutualistic plant-pollinator networks according to their connection similarity. We find that EM recovers largely the same clustering of the species as an alternative recently proposed method based on resource overlap, where one considers each party as a consuming resource for the other party (plants providing food to animals, while animals assist the reproduction of plants). Furthermore, using the EM algorithm, we can obtain a sequence of successfully-refined classifications that enables us to identify the fine-structure of the ecological network and understand better the niche distribution both for plants and animals. This is an example of how information theoretical methods help to systematize and unify work in ecology.
A High Temperature Experimental Characterization Procedure for Oxide-Based Thermoelectric Generator Modules under Transient Conditions
Authors: Man Elena , Schaltz Erik , Rosendahl Lasse , Rezaniakolaei Alireza , Platzek Dieter
Published: November 2015

The purpose of this study is to analyze the steady-state and transient behavior of the electrical and thermal parameters of thermoelectric generators (TEGs). The focus is on the required wait-time between measurements in order to reduce measurement errors which may appear until the system reaches steady-state. By knowing this waiting time, the total characterization time can also be reduced. The experimental characterization process is performed on a test rig known as TEGeta, which can be used to assess the output characteristics of TEG modules under different load values and temperature conditions. The setup offers the possibility to control the hot side temperature up to 1000 °C with a load variation range value between 0.22–8.13 Ω. A total of ten thermocouples are placed in the setup with the purpose of measuring the temperature in specific points between the heater and the heat sink. Based on the readings, the temperature on the hot and cold side of the modules can be extrapolated. This study provides quantitative data on the minimum waiting time of the temperatures in the surrounding system to reach equilibrium. Laboratory tests are performed on a calcium-manganese oxide module at temperatures between 400 and 800 °C to explore the high temperatures features of the setup.
Economic Evaluation on Bio-Synthetic Natural Gas Production Integrated in a Thermomechanical Pulp Mill
Authors: Zhang Wennan , He Jie , Engstrand Per , Björkqvist  Olof
Published: November 2015

In this study, biorefinery as a concept is applied to thermomechanical pulp (TMP)-based paper production to evaluate the possibility of co-production of synthetic natural gas (SNG), electricity and district heating in addition to mechanical pulp and paper. The combined heat and power plant (CHP) associated to TMP is replaced by a biomass-to-SNG (BtSNG) plant. Implementing BtSNG in a mechanical pulp production line might improve the profitability of a TMP mill and also help to commercialize the BtSNG technology by taking into account of some key issues such as biomass availability, heat utilization, etc. A TMP + BtSNG mathematical model is developed with ASPEN Plus. The model prediction shows that the scale of the TMP + BtSNG mill and SNG price are two strong factors for the implementation of BtSNG in a TMP mill. A BtSNG plant associated to a TMP mill should be built at a scale above 100 MW of biomass thermal input. For the case of Swedish economic condition, commercialization of SNG production as a transport biofuel has not matured yet. Political instruments to support commercialization of transport biofuel are necessary.
Modeling and Optimization of the Medium-Term Units Commitment of Thermal Power
Authors: Liao Shengli , Li Zhifu , Li Gang , Wang Jiayang , Wu Xinyu
Published: November 2015

Coal-fired thermal power plants, which represent the largest proportion of China’s electric power system, are very sluggish in responding to power system load demands. Thus, a reasonable and feasible scheme for the medium-term optimal commitment of thermal units (MOCTU) can ensure that the generation process runs smoothly and minimizes the start-up and shut-down times of thermal units. In this paper, based on the real-world and practical demands of power dispatch centers in China, a flexible mathematical model for MOCTU that uses equal utilization hours for the installed capacity of all thermal power plants as the optimization goal and that considers the award hours for MOCTU is developed. MOCTU is a unit commitment (UC) problem with characteristics of large-scale, high dimensions and nonlinearity. For optimization, an improved progressive optimality algorithm (IPOA) offering the advantages of POA is adopted to overcome the drawback of POA of easily falling into the local optima. In the optimization process, strategies of system operating capacity equalization and single station operating peak combination are introduced to move the target solution from the boundary constraints along the target isopleths into the feasible solution’s interior to guarantee the global optima. The results of a case study consisting of nine thermal power plants with 27 units show that the presented algorithm can obtain an optimal solution and is competent in solving the MOCTU with high efficiency and accuracy as well as that the developed simulation model can be applied to practical engineering needs.
Industrial Photovoltaic Systems: An Economic Analysis in Non-Subsidized Electricity Markets
Authors: Cucchiella Federica , D’Adamo Idiano , Rosa Paolo
Published: November 2015

Photovoltaic (PV) systems are becoming a relevant electricity source, characterised by a growing trend in the last years. This paper analyses the economic feasibility of investments in industrial PV systems of different sizes (200 kW, 400 kW, 1 MW, and 5 MW), in the absence of subsidies, and in a mature market (Italy). The selected indicators for this kind of assessment are net present value (NPV) and discounted payback time (DPBT). Furthermore, the environmental advantage in comparison to fossil sources of energy is evaluated through the reduction of carbon dioxide emissions (ERcd). Finally, a sensitivity analysis on critical variables (percentage of self-consumed energy, average annual insolation rate, annual electricity purchase price, annual electricity sale price, unitary investment cost and opportunity cost) is conducted. Results highlight the strategic role of self-consumption in a market characterised by an absence of public policy incentives and the presence of interesting economic opportunities for industrial applications.