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Continuous-Carbon-Fiber (CF)/polyaryletherketone (PAEK) composites have recently attracted interest especially in the aerospace industry due to short-time processes and possible weldability and recyclability. However, their manufacturing remains challenging as it involves several steps such as tape fabrication, tape lay-up and consolidation. This last step mainly aims at achieving a sufficiently low void content composite to obtain the desired mechanical properties. To become an economically viable alternative over classical thermoset-based composites, “in-situ” or out-of-autoclave (OOA) consolidation processes have to become part of the manufacturing process of CF/PAEK. These techniques have, for now, some limitations which lead to difficulties in producing parts of the same quality as autoclave consolidated ones. Understanding the multi-scale rheological phenomena involved during consolidation is therefore critical, which constitutes the main goal of this review. Reflecting on the literature, guides for improving the OOA and “in-situ” consolidation, both in terms of process and materials, are finally suggested.

International audience; Objective - The potentialities of improving the penetration of millimeter waves for breast cancer imaging are here explored. Methods - A field focusing technique based on a convex optimization method is proposed, capable of increasing the field level inside a breast-emulating stratification. Results - The theoretical results are numerically validated via the design and simulation of two circularly polarized antennas. The experimental validation of the designed antennas, using tissue-mimicking phantoms, is provided, being in good agreement with the theoretical predictions. Conclusion - The possibility of focusing, within a lossy medium, the electromagnetic power at millimeter-wave frequencies is demonstrated. Significance - Field focusing can be a key for using millimeter waves for breast cancer detection.

Background: Pediatric cardiac surgery is commonly associated with acute kidney injury (AKI) and significant fluid retention, which complicate postoperative management and lead to increased rates of morbidity. This meta-analysis aimed to accumulate current literature evidence and evaluate the correlation of fluid overload degree with adverse outcome in patients undergoing congenital heart surgery. Methods: Medline, Scopus, CENTRAL, Clinicaltrials.gov, and Google Scholar were systematically searched from inception. All studies reporting the effects of fluid overload on postoperative clinical outcomes were selected. A dose-response meta-analytic method using restricted cubic splines was implemented in R-3.6.1. Results: Twelve studies were included, with a total of 3111 pediatric patients. Qualitative synthesis indicated that fluid overload was linked to significantly higher risk of mortality, AKI, prolonged hospital, and intensive care unit (ICU) stay, as well as with increased duration of mechanical ventilation, inotrope need, and infection rate. Meta-analysis demonstrated a linear correlation between fluid overload and the risk of mortality (χ2 = 6.22, p value = 0.01) and AKI (χ2 = 35.84, p value < 0.001), while a positive curvilinear relationship was estimated for the outcomes of hospital (χ2 = 18.84, p value = 0.0001) and ICU stay (χ2 = 63.69, p value = 0.0001). Conclusions: The present meta-analysis supports that postoperative fluid overload is significantly linked to elevated risk of prolonged hospital stay, AKI development, and mortality in pediatric patients undergoing cardiac surgery. These findings warrant replication by future prospective studies, which should define the optimal cutoff values and assess the effectiveness of therapeutic strategies to limit fluid overload in the postoperative setting. © 2020, IPNA.

BACKGROUND The search for reliable techniques to assess gait in stroke patients is crucial for the design and follow-up of rehabilitation programs. OBJECTIVE To assess the reproducibility of kinematic and kinetic gait parameters in chronic stroke patients using a three-dimensional gait analysis system. METHODS Ten chronic stroke patients were assessed while walking along a 20 m walkway at their natural speed, using a gait analysis system of six infrared cameras and two force plates. Each patient performed 10 gait trials on 2 separate days. Inter-measurement agreement was assessed with the Coefficient of Multiple Correlation, while Root Mean Square Differences were used to quantify the variability of the trials. RESULTS The majority of kinetics and kinematics showed excellent reproducibility in all patients. Joints' power seemed to be more reliable compared with joints' angle and moment. Most parameters presented greater variability in non-paretic than the paretic leg, while they were less variable in the sagittal compared with the non-sagittal planes. Less than 10 trials were sufficient to obtain excellent reproducibility for most kinematic and kinetic parameters. CONCLUSIONS The reproducibility of movement assessment through three-dimensional gait analysis appears excellent in chronic stroke patients.

A corrosion protection of Stainless Steel (Grade 304) with low-cost commercial organic coatings (paints) was investigated in this study. Air sprayed Polyurethane (PU)-, Epoxy- and Acrylic-based commercial paints on the above substrate were tested for their anticorrosion properties in prospect of potential application for the protection of condensing economizers from industrial flue gases. PU and Epoxy coatings exhibited better corrosion protection efficiency of stainless steel than the acrylic coatings with values of 40, 39 and 28.1% respectively. This is in total agreement with corrosion current density trend calculated from potentiodynamic polarization curves. Corrosion rates of coatings in 3.5% wt NaCl aqueous solutions were calculated at 0.065, 0.067 and 0.071 mpy for Epoxy, PU and Acrylic coatings respectively. Condensation phenomena and water collection rates (WCR) at various conditions are also provided. The highest WCR exhibited on the epoxy coatings reaching 1.987 ml m -1 h -1 at 40 o C and 100% RH. These data provide a full dataset for the designers of condensing economizer systems willing to incorporate organic coatings either at structural components or as touch up solutions.

Contrast-induced nephropathy represents a major source of morbidity in patients undergoing coronary angiography. Various preventive measures have been proposed, although the optimal one remains still unknown. The aim of the present meta-analysis is to accumulate current literature knowledge and evaluate the renoprotective effects of allopurinol administration before contrast medium exposure. To achieve this, MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, Clinicaltrials.gov, and Google Scholar databases were searched from inception to November 8, 2018. Statistical meta-analysis was conducted with Review Manager 5.3, TSA 0.9.5.5 and R-3.4.3. Six studies were included with a total of 918 patients. Quantitative synthesis revealed that allopurinol leads to significantly reduced incidence of contrast-induced nephropathy compared with hydration alone [odds ratio: 0.29, 95% confidence interval: (0.09-0.90)]. Trial sequential analysis suggested that Z-curve crossed the O'Brien-Fleming significance boundaries, although required information size was not reached. Network meta-analysis indicated that allopurinol had the highest probability (81.2%) to rank as the most effective intervention compared with hydration and N-acetyl cysteine; however, significant overlap with the rest treatments was noted. In conclusion, the present meta-analysis suggests that allopurinol may represent a promising measure for the prevention of acute kidney injury after coronary angiography. Future large-scale randomized controlled trials should verify this finding, while combinations of allopurinol with other novel interventions should be evaluated to define the most effective strategy to be implemented in the clinical setting. © 2019 Wolters Kluwer Health, Inc.

Background: Acute kidney injury constitutes a major complication of cardiac surgery in pediatric patients. The present meta-analysis aims to accumulate current literature and assess the efficacy of pharmacological interventions in preventing postoperative renal dysfunction after congenital heart surgery. Methods: Literature search was conducted using Medline (1966–2018), Scopus (2004–2018), Cochrane Central Register of Controlled Trials CENTRAL (1999–2018), Clinicaltrials.gov (2008–2018), and Google Scholar (2004–2018) databases. Statistical analysis was performed with Review Manager 5.3 and R 3.4.3. Results: Meta-analysis included 14 studies, with a total of 2,625 patients. AKI incidence was significantly lower in the dexmedetomidine (OR 0.49, 95% CI [0.28–0.87]) and acetaminophen (OR 0.43, 94% CI [0.28–0.67]) groups, while no difference was present in patients receiving corticosteroid (OR 1.16, 95% CI [0.69–1.95]), fenoldopam (OR 0.47, 95% CI [0.22–1.02]), or aminophylline (OR 0.98, 95% CI [0.29–3.34]). Network meta-analysis proposed that dexmedetomidine had the greatest probability (44.5%) to rank first, although significant overlap with the other treatments was observed. Conclusions: The present meta-analysis suggests that no firm evidence exists about the protective role of pharmacological interventions in the pediatric population. Future randomized controlled trials should clarify the effectiveness of dexmedetomidine and acetaminophen and indicate the optimal protocol to be applied, to protect renal function in the perioperative setting. © 2019, Japanese Society of Nephrology.

International audience; The generation of several beams with strict radiation requirements in the field of a radiating aperture is demonstrated here. An optimization scheme is adopted to derive the aperture-field distribution generating the required near-field radiation. The optimization tool is based on a set-theoretic approach and takes into account field constraints on the radiation profile and polarization. The challenging case of generating four independent beams in the near field of a radiating aperture and with different polarizations is then considered. A tensorial metasurface is adopted to synthesize the derived aperture field profile to fully control the amplitude and phase distribution of the radiating aperture. Measurement results at 20 GHz validate the proposed approach.

Objective: To evaluate the efficacy and safety of tolvaptan in fluid management after cardiac surgery compared with conventional diuretic treatment. Design: Systematic review of the literature with meta-analyses. Setting: The Medline, Scopus, Cochrane Central Register of Controlled Trials, Clinicaltrials.gov, and Google Scholar databases were searched from inception to July 30, 2018. Participants: The study comprised 759 patients undergoing cardiac surgery. Interventions: Tolvaptan administration (n = 397) or standard diuretic therapy (n = 398). Measurements and Main Results: Ten studies were included in the present meta-analysis. Tolvaptan administration was associated with a significantly faster return to preoperative body weight (mean difference [MD)] –1.48 d, 95% confidence interval [CI] –1.92 to 1.03), shorter duration of hospital stay (MD –2.58 d, 95% CI –5.09 to –0.07), lower incidence of acute kidney injury (odds ratio 0.34, 95% CI 0.16-0.69), and greater urine output (MD 0.47 L/d, 95% CI 0.25-0.69) and sodium levels (MD 2.85 mEq/L, 95% CI 1.90-3.80). No significant differences were present regarding duration of intensive care unit stay (MD –0.09 d, 95% CI –0.33 to 0.15), arrhythmia incidence (odds ratio 0.58, 95% CI 0.33-1.02), and serum creatinine values (MD –0.08 mg/dL, 95% CI –0.20 to 0.04). Conclusions: The outcomes of the present meta-analysis suggest the promising role of tolvaptan administration in the management of fluid retention in patients after cardiac surgery. Future large-scale clinical trials should be conducted to fully elucidate its efficacy and to assess the optimal treatment protocol to be applied in the clinical setting. © 2018 Elsevier Inc.

International audience; Antenna near-field focusing is a research topic that is recently attracting attention, due to its impact on a wide number of trending applications. In this communication we propose a methodology based on convex optimization to focus the scalar field radiated by planar continuous apertures. The methodology is capable to focus the field inside piecewise stratified media and is supported by an easy-to-implement MATLAB package. In addition, we apply specific optimization goals which render the resulting aperture distributions realizable. © 2017 IEEE.

Variability of CzeV843 Cen was detected 31 March 2016 in the FOV of V834 Cen using Dk154 telescope at La Silla.

International audience; Medical imaging using electromagnetic waves is a promising field of study, due to its non invasive nature and relatively low cost. Typically, it is pursued at frequencies in the microwave regime to provide adequate penetration depth. However, an increase of the frequency of operation is beneficial in order to improve the resolution, but it is accompanied by increased tissue losses. In this work we investigate the possibility to increase the penetration depth of systems for breast imaging at the lower bound of millimeter waves (30 GHz). The proposed technique consists in a near-field focusing of the radiated field with an enhanced penetration depth. © 2017 IEEE.

In questo studio sono state integrate osservazioni tipologiche, condotte su forme a vernice nera rinvenute a Palermo, Termini Imerese, Monte Iato e Marineo, con i dati ricavati dalla caratterizzazione mineralogica, petrografica e chimica degli impasti. I 55 campioni selezionati appartengono a due forme : un piatto («Lamboglia 36 » , serie 1310-1320 di J.-P. Morel), tra i più comuni nella Campana A di I e II secolo a. C. ; ed una coppa di produzione locale o regionale, attestata (fine IV-III secolo a. C.) in insediamenti della Sicilia nord-occidentale, che è stata utilizzata anche come «gruppo di riferimento » chimicopetrografico. Sono stati distinti due gruppi composizionali, da ascrivere uno all’area del Golfo di Napoli, l’altro ad ambito produttivo locale, che per le caratteristiche mineralogico-petrografiche e chimiche è riferibile alle Argille di Ficarazzi (periferia orientale di Palermo). Ad entrambi i gruppi appartengono reperti del piatto Lamboglia 36, ma solo al secondo i campioni della coppa., Belvedere Oscar, Burgio Aurelio, Iliopoulos Ioannis, Montana Giuseppe, Spatafora Francesca. Ceramica a vernice nera di età ellenistica da siti della Sicilia nord-occidentale : considerazioni tipologiche ed analisi archeometriche. In: Mélanges de l'École française de Rome. Antiquité, tome 118, n°2. 2006. Antiquité. pp. 549-571.

In this work a methodology to shape the near field of radiating apertures is presented. The technique, despite being generic, is applied to the specific scenario of shaping the focal pattern of a 12λ focusing aperture at 30 GHz. The main result comprises the capability to shrink/enlarge the focal depth, without affecting the spot diameter. To verify the concept, the acquired aperture distribution is mapped on a Radial Line Slot Antenna (RLSA), which has been manufactured and measured, showing excellent results.

International audience; This work aims at showing the feasibility of performing 2D near-field focusing using a Leaky-Wave Lens (LWL) based on Sinusoidally Modulated Reactance Surfaces (SMRS). The polarization of the field at the focus is perpendicular to the antenna aperture, due to the geometry of the structure. Electrically small focal distances are achieved, combined with very small spot diameters. The limitations of this approach are discussed, which are mainly related to the prediction of the focal point. The concept is proven by simulations and experimental testing is in progress. © 2016 European Association of Antennas and Propagation.

International audience; The near-field (NF) regime is a highly challenging and rather unstudied area of electromagnetic (EM) fields due to the high mathematical complexity that it presents. Nevertheless, the evanescent fields, present within the near field, can offer extra flexibility and freedom in molding the close-to-the-antenna field. In this work we develop an algorithm capable to shape the EM fields according to specifications in 3D regions at distances within the near-field and Fresnel region of the radiating device. The algorithm is based on a set theoretic approach and a frontand- back iterative propagation scheme, where the use of FFT is playing a key role in speeding up the algorithm's application. A prototype using a Radial Line Slot Antenna (RLSA) topology has been manufactured to prove the concept.

International audience; The manipulation of the near field (NF) is a challenging topic of electromagnetics, carrying essential importance for several applications. In this work, we develop an algorithm capable of shaping the near field in 3D domains according to given specifications. The algorithm is based on a set theoretic approach and a front-and-back iterative propagation scheme. The latter is realized using Fast Fourier Transforms (FFT), reducing the required computational time. The algorithm is applied on a focal shaping scenario. In this case, a full control of the depth of focus, spot diameter and sidelobe level of the generated radiation is achieved. In particular, the proposed procedure is successfully adopted to control the normal component of a radiating aperture over a range of 12 at 30 GHz. The derived aperture field distribution is then synthesized by a Radial Line Slot Antenna (RLSA) by means of an in-house Method of Moments (MoM) code. Near-field measurements have validated the proposed approach and prototype.

Various blends approaches based on PS-b-PMMA block-copolymers (BCP) systems are studied. The impacts of the different components in the blends on various basic characteristics of interest for lithographic applications are highlighted. More specifically, we show how such approaches can be managed to get a tight control over the different dimensions of the self-assembly, and reach lower defects levels than a single pure BCP. These methods could greatly help the BCP self-assembly technology to be introduced as an actual lithographic technic to further reduce achievable dimensions.

Background: Little information on costs and quality of life (QoL) of patients with Multiple Sclerosis (MS) has been published for Greece so far. Objective: The objective of the study was to assess the socio-economic burden that MS imposes to Greek patients with relapsing forms of multiple sclerosis. Methods: Information on demographics, disease history, resource consumption and productivity losses was collected from 200 patients recruited in six MS centres throughout Greece. Annual costs were estimated in 2011 unit costs. Health-related QoL (HRQoL) was measured with the EQ-5D questionnaire. Using the Expanded Disability Status Scale (EDSS), patients were stratified into those with mild (EDSS 0-3), moderate (EDSS 3.5-6.0) and severe (EDSS 6.5-7.5) disability. The perspective of the analysis was that of the national security fund (EOPYY). Results: The mean annual cost per patient was estimated at €26,118. Higher disability increased costs substantially; €20,702 for mild, €32,126 for moderate and €45.442 for high severity patients. HRQoL was considerably impaired by disease progression. Patients with Secondary Progressive (SPMS) as expected had higher costs and lower HRQoL than Relapsing Remitting Multiple Sclerosis (RRMS) subjects, attributed to higher mean disability. Conclusion: In accordance with other studies, MS imposes a considerable health and economic burden in Greece, which increases significantly with advancing disability.

We studied the effect of topically applied phenytoin on the healing of a decubitus ulcer in the sacral region of an immobile patient with stroke. Another similar, but smaller, ulcer was treated with conventional treatment only and served as a control. The ulcers were measured once a week and biopsies were taken from the margins before, 1 week and 2 weeks after commencing treatment with phenytoin. Clinically, phenytoin substantially accelerated the rate of healing. Microscopic examination of the biopsies showed increased lymphocytic infiltration of the phenytointreated lesion. Anti-CD31 immunohistochemistry revealed dense CD31+ lymphocytic infiltration and increased angiogenesis only in the phenytointreated lesion. Our findings suggest that phenytoin enhances wound healing by stimulating lymphocytic chemotaxis and up-regulation of angiogenesis.

The association mechanism of several hydrophobically modified sodium polyacrylates (HMPA) in aqueous solutions has been investigated by fluorescence probing with pyrene as the fluorescent probe, by electrical conductivity, and by 13C NMR. The investigated HMPAs differed by the molecular weight of the poly(acrylic acid) precursor, the degree of hydrophobe substitution, and the carbon number of the hydrophobe (alkyl chain). The results showed that the association of HMPAs is less cooperative than the micellization of conventional surfactants and that there is a concentration below which no micelle-like aggregates are present in the systems. 13C NMR studies showed that only a fraction Faggr of hydrophobes is involved in the formation of hydrophobic microdomains, and that Faggr increases with the hydrophobe length and degree of substitution. The combination of the values of Faggr with the hydrophobic microdomain concentration, obtained from steady state and time-resolved fluorescence quenching measurements, a...

We report on the synthesis and the properties of a novel water soluble polymer based on two comonomers, one hydrophobic and one amphiphilic: styrene and dimethylhexadecyl(vinylbenzyl)ammonium chloride, respectively. The behavior of aqueous solutions of the copolymer has been studied by rheology and compared with the properties of its polyelectrolyte and polysoap homologues. At concentration as low as 2% (w/w), they exhibit gel characteristics despite the low degree of polymerization of the copolymer chains (DP n ≅70). By analogy to surfactants, this suggests the formation of elongated aggregates involving several polymer chains. The birefringence shown by the solutions is a way to probe the formation of these superstructures inside the solution.

Pantellerian ware is a Late Roman cooking ware whose production centre was established on the island of Pantelleria by the pioneering research of Fulford and Peacock almost 20 years ago (Peacock 1982; Fulford and Peacock 1984). Archaeological and archaeometric studies carried out by the authors of the present contribution during the past four years have aimed to fully characterize this ceramic class. Recurrent ceramic forms, their distribution over time and space, their petrographic characteristics and their chemical identity, as well as possible raw materials and their technological properties, were considered. The present paper is a comprehensive review of this archaeometric work and aims to establish a ‘reference group’. Using a representative number of samples of Pantellerian ware that were recently discovered in the island through archaeological field surveys or surface and submarine excavations, it was possible to characterize in detail the compositional variability of this ware in terms of chemistry and petrography. Furthermore, the physical properties of this ceramic type have been defined in order to better understand its performance characteristics, mainly in response to induced thermal stress. In the meantime, the experimental mixing and tempering of locally sampled raw materials have shed light on the ancient manufacturing process and have led to an approximation of the original paste.

In this paper, we present some preliminary results on the phase behaviour of amphiphilic polyelectrolytes, derivatives of poly(vinyl benzyl chloride). The phase diagram of these copolymers contains, depending on the amount of amphiphilic units and on the polymer concentration, five different domains: an isotropic liquid and isotropic gel, a birefringent gel, a gel birefringent under stirring and a demixed gel.

International audience; The spontaneous self-assembly of a novel comb-like amphiphilic copolyelectrolyte in water was studied by small angle neutron scattering and freeze fracture transmission electron microscopy. The copolymer was synthesized by randomly grafting pendant quaternized alkylamine moieties to a poly(styrene) chain. The effects of the grafting density and the length of the alkyls (C12-C18) on the structure were investigated systematically. The polymers were soluble over a broad range of grafting densities (35-80 mol%) where they assembled either into lamellae (35-55 mol%) consisting of a double layer of polymers or cylinders (65-80 mol%) formed by bundling of several chains. At higher concentrations, electrostatic repulsion drove smectic and hexagonal ordering of, respectively, the lamellae and the rods. TEM images showed micro-domains of stacked lamellae that were in some cases closed upon themselves to form onion-like particles. Exposure of hydrophobic patches at the surface due to defects of the self-assembly led to the formation of bonds between lamellae or cylinders. As a consequence visco-elastic solutions or hydrogels were formed at higher concentrations.

We report on the effects on the phase behavior in the water-rich part of the ternary nonionic surfactant system, pentaethylene glycol dodecyl ether (C 12 E 5 )-water-decane, when adding sodium polyacrylate (PA) or hydrophobically modified polyacrylate (HMPA). The polyelectrolytes, having the same degree of polymerization, were derived from polyacrylic acid of M w = 150 000. The HMPA contains hydrophobic octadecyl side chains randomly anchored to the polyelectrolyte backbone, with a degree of modification of either 1 or 3% of the monomer units. The PA is found to be insoluble in the lamellar liquid crystalline and the liquid L 3 phases, containing infinite bilayer aggregates, while it is soluble in the liquid L 1 phase containing oil-swollen normal micelles. The HMPA, on the other hand, can be solubilized in all three phases, however, strongly affecting the phase equilibria. From the difference it is concluded that while PA is nonadsorbing, HMPA adsorbs to the surfactant film by the hydrophobic stickers. In the presence of HMPA the surfactant films behave as effectively charged with long-range electrostatic interactions and a positive shift of the spontaneous mean curvature. The lamellar phase containing the HMPA phase separates at higher bilayer concentrations into two lamellar phases in equilibrium. Here a HMPA-rich lamellar phase with larger water spacings coexists with a lamellar phase of smaller water spacings essentially free of HMPA.

We have investigated the association of hydrophobically modified poly(sodium acrylate) (HMPA) to micelles and bilayers of nonionic surfactant. The HMPA bears octadecyl chains randomly anchored on 1 or 3 mol% of the monomer units, and the surfactant is pentaethylene glycol dodecyl ether (C 12 E 5 ) or octaethylene glycol dodecyl ether (C 12 E 8 ). The HMPA was introduced in small amounts to the micellar and lamellar phases of the binary nonionic surfactant/water system. The association of HMPA with the nonionic surfactant aggregate is due to the hydrophobic alkyl chains of the polymer that dissolve in the surfactant film

Chronic necrotizing pulmonary aspergillosis is a rare infection encountered mainly in immunocompromised patients. We present the case of a young woman where the diagnosis of chronic necrotizing pulmonary aspergillosis was established after an open biopsy of the right lung. Liposomal amphotericin B was administered postoperatively for 10 days with moderate success. In a concise review we summarize the basic notions of chronic necrotizing pulmonary aspergillosis.

The formation of polymer complexes was studied between poly(ethylene oxide) (PEO) and poly(N-vinylpyrrolidone) (PVP), as hydrogen-bond acceptors and copolymers of acrylic acid (AA) with vinylsulfonic acid (VS) or with 2-acrylamido-2-methylpropanesulfonic acid (AMPS) as hydrogen-bond donors. Under acidic conditions (e.g., pH≃3), the strong-acid groups (VS or AMPS) are dissociated and uncomplexable, while the carboxylic groups (COOH) can be complexed by the polybase (PEO or PVP). Potentiometric and viscometric studies showed that the properties and the structure of the complexes formed depend on the experimental parameters: molar content of sulfonated monomers, concentration of polyacid and polybase, molecular weight of polymers, and nature of polybase

The association between a cationic hydrophobically modified polyelectrolyte and an anionic surfactant was investigated in bulk solution and at a negatively charged solid surface. The bulk association was followed by measurements of turbidity and electrophoretic mobility. The maximum turbidity of the solution was found to closely coincide with the point of zero electrophoretic mobility of the aggregates. The forces acting between negatively charged mica surfaces across a dilute aqueous solution of the hydrophobically modified polyelectrolyte were monitored using surface force measurements. The presence of hydrophobic side chains on the polyelectrolyte leads to adsorption in an inner rather compact layer and an outer extended layer. After dilution only the inner layer remains adsorbed to the surface. In the next step, sodium dodecyl sulphate (SDS) was added. It was found that the anionic surfactant is incorporated in the adsorbed layer even at very low bulk concentrations. As the surfactant concentration is increased stepwise the layer first swells and relaxes very slowly during compression. At higher SDS concentrations, desorption occurs. The interfacial properties of the hydrophobically modified polyelectrolyte alone and in mixtures with SDS are in many ways strikingly different to those of non-hydrophobically modified polyelectrolytes having a similar linear charge density. This is due to the importance of hydrophobic interactions between the hydrophobic side chains of the polyelectrolyte and between these groups and the non-polar part of the surfactant.

Symptoms of disequilibrium in multiple sclerosis (MS) are common. Neurogenic vestibular evoked potentials (NVsEPs) are saccular responses to tone-pip acoustic stimuli and are recordable from the parietal areas ipsilaterally to the stimulated ear. We wished to determine possible correlations of abnormal findings in NVsEP with clinical neurological findings related to the vestibular system, and demyelination seen on MRI.NVsEPs were performed by delivering a 1 kHz tone-pip stimulus monoaurally with contralateral masking noise via headphones. Brainstem auditory evoked potentials were performed in the standard manner.Thirty-three patients had either been diagnosed with MS or had possible MS. There is statistical evidence that the presence of symptoms is likely to give an abnormal NVsEP, but no correlation exists between the presence or absence of vestibular symptoms and signs and an abnormal BAEP. No correlation was found between the presence of brainstem lesions on MRI and an abnormal NVsEP. Correlation exists between abnormal NVsEP and the level of disability using Expanded Disability Status Scale scores.We have found that with increasing involvement of abnormal NVsEPs, there is a significant correlation with symptoms and signs that can be referred to the vestibular system.

To demonstrate that neurogenic vestibular evoked potentials (NVsEP) may be specific to the vestibular system using three cases of vestibular system dysfunction and normal auditory function,Neurogenic vestibular evoked potentials were performed by recording from the parietal areas of the scalp using a tone-pip auditory stimulus via headphones. Brainstem auditory evoked potentials (BAEPs) and NVsEP were performed in all three cases.Brainstem auditory evoked potentials were within normal limits in all three cases. All three patients showed abnormalities in their NVsEP In the third case, the responses normalized after treatment.The findings support further the hypothesis that NVsEP are specific to the vestibular system and are a separate response from the BAEP SIGNIFICANCE: Neurogenic vestibular evoked potentials is an easy examination to carry out and can be performed in any clinical neurophysiological laboratory that is familiar with BAEPs. Examinations used to diagnose vestibular system disorders at present include the glycerol dehydration test, electrocochleography, myogenic vestibular evoked potentials and electronystagmography. Neurogenic vestibular evoked potentials may also prove to be useful.

Chemical analysis is a well-established procedure for the provenancing of archaeological ceramics. Various analytical techniques are routinely used and large amounts of data have been accumulated so far in data banks. However, in order to exchange results obtained by different laboratories, the respective analytical procedures need to be tested in terms of their inter-comparability. In this study, the schemes of analysis used in four laboratories that are involved in archaeological pottery studies on a routine basis were compared. The techniques investigated were neutron activation analysis (NAA), X-ray fluorescence analysis (XRF), inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). For this comparison series of measurements on different geological standard reference materials (SRM) were carried out and the results were statistically evaluated. An attempt was also made towards the establishment of calibration factors between pairs of analytical setups in order to smooth the systematic differences among the results.

In eukaryotes the DnaJ homolog constitute a family of proteins with diverse functions which all appear to involve the chaperone activity of Hsp70. Here, we report the molecular characterization of DnaJ60, a gene located at 60C on the right arm of the second chromosome of Drosophila melanogaster and encoding a putative protein of 217 amino acids with a molecular mass of 27.7-kDa and a pl of 10.5. The N-terminal region of the DnaJ60 protein displays a significant sequence similarity with the J domain of DnaJ proteins and contains a centrally located hydrophobic segment suggesting the occurrence of a membrane spanning domain. Northern blot analysis detected a 0.75-kb transcript which is weakly expressed in embryos, larvae and females but intensively expressed in adult males. In situ localization revealed that the DnaJ60 transcript is highly expressed in male testes and the ejaculary bulb but at an undetectable level in ovaries suggesting that the DnaJ60 protein may play an important function during spermatogenesis and/or in the male genital tract.

Viscometry and fluorescence spectroscopy are used to study the dilute solution behavior of hydrophobically modified polyelectrolytes. Random copolymers of sodium acrylate and alkylacrylamide are used for this study. The alkylacrylamide content is low, 1–3 mol%, and the length of the alkyl group ranges from octyl to octadecyl. Upon addition of NaCl these copolymers exhibit a transition from a nonaggregated coil to an aggregated one. The transition occurs above a critical salt concentration which is dependent on the length and the content of alkyl groups. This behavior is ascribed to the formation of intrachain hydrophobic aggregates. The copolymer with the shortest alkyl chain (octyl) does not exhibit such aggregation at least in the range of salt concentrations studied, i.e. ≤ 15% NaCl.

Thrombosis of the central venous system (CVT) occurs in 20% to 30% of patients with indwelling catheters. This complication is usually treated with anticoagulation, extremity elevation, and catheter removal. Thirty-eight patients with CVT at our institution were treated with thrombolytic therapy to rapidly resolve symptoms and avoid removal of the catheters. Complete clot lysis occurred in 36 of 38 patients (95%) within 1 to 5 days (mean: 2.4 days). Symptoms resolved with clot resolution. Thrombolytic therapy detected stenoses in 22 patients. Angioplasty was successful in 64% of these patients. Five catheters were removed. Complications occurred in six patients: nonfatal pulmonary embolus, three bleeding episodes, pain with infusion of urokinase, and an episode of septic phlebitis. This experience suggests that thrombolytic therapy is safe, rapidly resolves symptoms of thrombosis, uncovers anatomic abnormalities amenable to angioplasty, and allows central venous catheters to remain in place despite central venous thrombosis.

The purpose of this study was to determine the significance of collateral supply from the hypogastric arteries (HGAs) to the inferior mesenteric arterial (IMA) bed. Peak systolic "stump" IMA and radial arterial pressures were obtained before and after clamping the right HGA, the left HGA, both HGAs, the middle colic artery (MCA) only, or the MCA plus right HGA, MCA plus left HGA, and MCA plus both HGAs in patients with aortoiliac aneurysm or occlusive disease. Six patients (four with aneurysms and two with occlusive disease) had patent IMAs. Five patients (four with aneurysms and one with occlusive disease) had chronically occluded IMAs. In the six patients with patent IMAs, clamping of the HGAs decreased the IMA-stump pressure index (IMA-SPI) from 0.61 +/- 0.20 to 0.56 +/- 0.17, 0.54 +/- 0.17, and 0.54 +/- 0.19, respectively (p greater than 0.05) whereas clamping only the MCA decreased the IMA-SPI from 0.61 +/- 0.20 to 0.32 +/- 0.15 (p less than 0.01). In the five patients with chronically occluded IMAs, clamping of the HGAs decreased the IMA-SPI from 0.60 +/- 0.11 to 0.59 +/- 0.12, 0.58 +/- 0.12, and 0.57 +/- 0.11, respectively (p greater than 0.05), whereas clamping the MCA decreased the IMA-SPI from 0.60 +/- 0.11 to 0.34 +/- 0.04 (p less than 0.01). These data suggest that branches of the superior mesenteric artery provide the major collateral pathway to the IMA bed and that the contribution through branches of the HGAs is insignificant in the acute setting.

Two hundred twenty-one patients undergoing thyroidectomy were analyzed for factors increasing the risk of postoperative hypocalcemia. Eighty-three percent of all patients experienced hypocalcemia postoperatively, with 13 percent requiring some treatment for symptoms. Patients with advanced thyroid cancer, Graves' disease, or other manifestations of preoperative hyperthyroidism had significantly increased rates of hypocalcemia compared with patients with small cancers or benign euthyroid disease. Total thyroidectomy, repeat thyroidectomy, and thyroidectomy plus neck dissection all significantly increased the incidence of permanent hypocalcemia, whereas lobectomy or subtotal thyroidectomy for benign euthyroid disease were low risk operations. Inadvertent excision of more than one parathyroid gland during thyroidectomy also significantly increased the rate of permanent hypocalcemia.

Twenty to thirty per cent of patients with arterial injuries and some patients with venous injuries require interpositional grafting. The first choice of grafting material for both arterial and venous injuries is autogenous vein. Injuries to large vessels such as the aorta and superior vena cava may necessitate synthetic prostheses. Synthetic aortic prostheses have excellent long-term patency rates, but the same materials are much less likely to remain patent in the vena cava. Panel or spiral grafts constructed from saphenous vein appear to be the best replacement for this vessel. Autogenous veins are present in different diameters ranging from a mean of 6.4 mm in the saphenous vein to a mean of 1.8 cm in the internal jugular vein. The thickest autogenous vein is the saphenous vein, and thus it is preferred for medium-sized and small arteries. The authors prefer the larger 7.5-mm cephalic vein for replacement of medium-sized veins. In the absence of suitable saphenous vein, the cephalic vein is also the choice for arterial interposition grafts. Although there are few reports of the use of arterial autografts in vascular trauma, the surgeon should be aware that autografts may be ideal for vascular injuries in children and for isolated injuries with severe contamination. Finally, the use of synthetic grafts in injuries where adequate tissue coverage is not possible may result in immediate limb salvage, but the incidence of limb loss in this situation will be extremely high.