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We develop a conductive-atomic force microscope coupled to a mid-infrared (IR) quantum cascade laser that allows to measure mid-IR photocurrent maps and spectra with nanometric spatial resolution. Here, we exploit the photo-induced thermoelectric effect of graphene to obtain the mid-IR local absorption spectra of nanoscale devices and materials. By scanning the probe in AFM-contact mode, the thermoelectric photocurrent can be mapped throughout the graphene layer, which acts as a semitransparent transducer. At zero voltage bias applied to the probe tip, we observe very low noise (about 25 pA/ Hz ), which makes our technique competitive with others in measuring the local IR absorption in nanomaterials with insufficient thermal expansion coefficient, or to characterize nanoscale devices that significantly absorb IR radiation, such as mid-infrared photodetectors. [ABSTRACT FROM AUTHOR]

Superconducting nanostrip single photon detectors have emerged as the highest performing single-photon detectors; however, the possibility to use superconducting microstrip as single photon detectors is very appealing both to use them as larger areas detectors and for an easier technology in the manufacturing. The aim of this work is to test the photoresponse in liquid helium dewar of 9 nm thick MoSi covered with a very thin (2 nm) layer of Al, in two different configurations: nanomeanders and microstrips. We demonstrate that MoSi/Al microstrips can work as photodetectors also at T = 4.2 K. We also compare the dark count rate of the microstrip and the nanowire, confirming the lower noise for the microstrips also at 4.2 K. [ABSTRACT FROM AUTHOR]

Objective: Tracheostomy is required to ensure a safe airway in open partial horizontal laryngectomies. The presence of the tracheostomy tube can contribute to post-operative dysphagia. This study aimed to evaluate the effects of a circumferential tracheostomy technique on swallowing. Methods: A retrospective study was conducted of patients who underwent open partial horizontal laryngectomies between April 2018 and June 2019. Patients were divided into two groups based on the tracheostomy technique: group 1 had two stitches from the inferior tracheal ring to the skin; group 2 had circumferential fixation of the trachea to the skin. Demographic information, surgical data, post-operative rehabilitation course and complication details were collected and analysed. Results: Twenty-four patients were enrolled. Patients in group 2 had significant improvement in the initial phases of swallowing rehabilitation. Conclusion: Tracheostomy with anchorage of the trachea to the skin by circumferential stitches could allow early removal of the tracheal tube, with a better swallowing outcome. [ABSTRACT FROM AUTHOR]

We determine the full photon number response of a NbN superconducting nanowire single photon detector via quantum detector tomography, and the results show the separation of linear, effective absorption efficiency from the internal detection efficiencies. In addition, we demonstrate an error budget for the complete quantum characterization of the detector. We find that for short times, the dominant noise source is shot noise, while laser power fluctuations limit the accuracy for longer timescales. The combined standard uncertainty of the internal detection efficiency derived from our measurements is about 2%. [ABSTRACT FROM AUTHOR]

We determine the full photon number response of a NbN superconducting nanowire single photon detector via quantum detector tomography, and the results show the separation of linear, effective absorption efficiency from the internal detection efficiencies. In addition, we demonstrate an error budget for the complete quantum characterization of the detector. We find that for short times, the dominant noise source is shot noise, while laser power fluctuations limit the accuracy for longer timescales. The combined standard uncertainty of the internal detection efficiency derived from our measurements is about 2%. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) is a promising candidate as a material platform for photonic quantum technologies due to the coexistence of quantum emitters and a non-centrosymmetric crystal structure. The realization of a single-photon detector was hampered from both the poor surface quality and the difficulties in micromachining this material. In this work, we realized superconducting nanowire single-photon detectors (SNSPDs) integrated on top of high-quality 3C SiC whose electro-optical characterization was performed thanks to a novel alignment method. We demonstrate that SNSPDs with high internal efficiency can be fabricated which is a fundamental building block toward the realization of complex architectures in this platform. [ABSTRACT FROM AUTHOR]

The transoral approach for enucleation of a voluminous odontogenic lesion involving the maxillary sinus is considerably invasive and can cause irreversible damage to the ciliated mucosa with definitive loss of the normal bone morphology. Functional endoscopic sinus surgery (FESS), which increases the patency of the osteomeatal complex (OMC), involves the use of a direct approach to the lesion, facilitating the drainage of secretions and improving the ventilation. Nevertheless, FESS cannot completely enucleate large odontogenic cystic lesions, particularly dentigerous cysts associated with dislocated teeth. Accordingly, a combined transnasal endoscopic and transoral approach is desirable. Here, we report the successful use of FESS combined with a conservative intraoral approach for the treatment of a voluminous dentigerous cyst that completely occupied the maxillary sinus. In a single surgery, FESS was used to enlarge OMC and open the cystic compartment into the nasal cavity, while an intraoral approach involving the removal of a bony lid from the anterolateral wall of the maxillary sinus facilitated minimal removal of the cystic wall associated with the dislocated tooth. The bony lid was repositioned and fixed with titanium plates. Computed tomography performed at 6 months showed that the original cystic compartment, which maintained communication with the nasal cavity through the enlarged OMC, was absent, and that the sinus had recovered its healthy morphology. Computed tomography at 27 months showed the maintenance of this status with no signs of recurrence. We recommend this approach to eradicate such pathology while preserving the sinus structure and function. [ABSTRACT FROM AUTHOR]

Superconducting meanders of NbN thin films have applications as single-photon detectors with high sensitivity in the infrared region. We report here a detailed analysis of the electrical characteristics of such meanders, by studying structures where each wire of the meander is separately contacted. The effect of heating on the superconducting-normal transition of adjacent stripes is evidenced. Moreover, the analysis of the switching current distribution of each wire highlights the high-critical current uniformity achieved by our meander process. [ABSTRACT FROM AUTHOR]

We have fabricated and characterized at low temperature, down to 0.32 K, tunnel junctions made by a thin film of heavily doped silicon in contact with superconducting electrodes through Schottky barriers. Doped silicon films were chemical vapor deposited on silicon-on-insulator substrates and laterally dry etched in mesas. Aluminum or, alternatively, niobium contacts were deposited on the mesas. Below the superconducting critical temperature T[sub c], an energy gap opens in the superconductor and the current–voltage characteristics become nonlinear and strongly sensitive to temperature changes. We have also characterized the heavily doped silicon in terms of the electron–phonon thermal decoupling by cooling the electron gas by means of aluminum–silicon–aluminum structures. With Nb electrodes, we have observed an anomaly of the electrical differential conductance at zero voltage and a larger electron dissipation, as a result of a less opaque barrier. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We discuss the thermal properties of small metal and insulating structures, interesting for bolometer applications. We report on the characterization of thin-film thermometers based on normal metalinsulator-superconductor tunnel junctions, operating at sub-Kelvin temperature and fabricated by using either niobium or aluminum as superconducting electrodes. The effect of different bias methods on the thermometer current-voltage characteristics is measured as well as the response of small metal structures to absorbed/removed power. The characterization is performed with a helium-3 refrigerator, compatible with the instrumentation generally available in ground or space-borne experiments. [ABSTRACT FROM AUTHOR]

We measured the transport properties and charge noise of superconducting single-electron transistors at the temperature of 0.3 K. The devices were fabricated with different ratios between charging and Josephson energies in order to explore their behavior in different experimental situations. We show that, in spite of the substantial thermal fluctuation, it is possible to extract from the data the values of the device parameters and information on the various tunneling mechanisms. Furthermore, we measured the device noise at different bias points, corresponding to regions with different dominant tunneling mechanisms, namely in the supercurrent, in the Josephson quasiparticle, and in the sequential tunneling regions. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Purpose: Generic drugs use in the Liguria region is higher than the Italian average, but lower than in other European countries. No data exist about real-life prescription and level of awareness of generic drugs. In this study, we analyzed demographic, social, economic and cultural factors that may affect the level of awareness of generic drugs and their effective use. Methods: We conducted a population survey using a structured questionnaire, administered to a sample of 8 outpatient clinics of general practitioners located in different districts of Genoa (Liguria, Italy). Multivariate logistic modeling was adopted to study the relationship between awareness/use of generic drugs and characteristics of subjects. Results: Out of 2,000 outpatients surveyed, 95% were aware of generic drugs: these were mostly females (OR =2.2, 95% CI: 1.4-3.6), .35 years old (OR .6.0 vs 18-35 years), with a high level of education (OR .4.4 vs "elementary sch"), living in the west side of the city (OR =1.9 vs center); of these, only 59% declared that they effectively use generic drugs. Users were younger (OR =3.1, 18-35 years vs .65 years), with a high level of education (high school/university degree vs no title/elementary/secondary school OR =1.7) and were aware of the lower cost compared with branded drugs, and were mainly informed by pharmacists and physicians. Conclusions: Although subjects were substantially aware of the existence of generic drugs, ∼40% still did not use them; doubts about their efficacy seem to be mainly driven by the idea that cheaper drugs lead to lower product quality, in terms of efficacy, safety and tolerability. New education policies on generic drugs are needed. [ABSTRACT FROM AUTHOR]

We measure the maximal distance at which two absorbed photons can jointly trigger a detection event in NbN nanowire superconducting single photon detector microbridges by comparing the one-photon and two-photon efficiencies of bridges of different overall lengths, from 0 to 400 nm. We find a length of 23±2 nm. This value is in good agreement with the size of the quasiparticle cloud at the time of the detection event. [ABSTRACT FROM AUTHOR]

What is known and objective Nalmefene, a new opioid system regulator, has recently been approved for the treatment of alcohol dependence, primarily for reducing heavy drinking days. Cases description Two patients with a diagnosis of alcohol use disorder were treated with nalmefene. Both patients developed fatigue and deep sleepiness after 2 days of treatment. Only after 1 day of drug discontinuation, symptoms normalized. What is new and conclusion We have analysed symptoms' development before and after treatment discontinuation and the possible association with nalmefene therapy. This case should pinpoint our attention on this adverse event for a careful choice of anticraving therapy in patients with severe alcohol use disorder. [ABSTRACT FROM AUTHOR]

Ketamine is an anaesthetic and analgesic drug synthesized in the 1960s from phencyclidine. The recreational use of ketamine increased among the dance culture of techno and house music, in particular in clubs, discotheques, and rave parties. The psychotropic effects of ketamine are now well known and they range from dissociation to positive, negative, and cognitive schizophrenia-like symptoms. We report a case of a chronic oral consumption of ketamine which induced agitation, behavioral abnormalities, and loss of contact with reality in a poly-drug abuser; these symptoms persisted more than two weeks after the drug consumption had stopped. Antipsychotic treatment with paliperidone led to a successful management of the psychosis, getting a complete resolution of the clinical picture. Paliperidone has proven to be very effective in the treatment of ketamine-induced disorders. Moreover, the pharmacological action and metabolism of paliperidone are poorly dependent from the activity of liver enzymes, so that it seems to be one of the best second generation antipsychotics for the treatment of smokers and alcohol abusers. [ABSTRACT FROM AUTHOR]

The Brief Repeatable Battery (BRB) of Neuropsychological Tests is one of the most widely used instruments to assess cognitive functioning in multiple sclerosis patients. However, to date, normative data for the Italian population are available only for the version A, which limits the use of the battery in longitudinal evaluations. We administered the BRB version B to 132 healthy subjects to obtain normative values taking into account the influences of demographic factors on the test scores and calculating corrections for these relevant factors (age, gender and education). Higher age and educational level were associated with better performance on all the tests. The World List Generation was also influenced by gender, since women performed better than men. Moreover, some tests of the version B seem to be easier than those of version A. Our data can improve the applicability of the BRB for both clinical and research purposes in longitudinal assessments. [ABSTRACT FROM AUTHOR]

Purpose: Although neuropsychological impairments are common in Multiple Sclerosis (MS), the manifestation of cognitive deficits may vary greatly across MS patients. Here, we explored the influence of cognitive reserve proxy indices (education and occupation) and perceived fatigue on cognitive performance. Methods: Fifty relapsing-remitting MS patients were evaluated. Cognitive performance was measured using the Paced Auditory Serial Addition Test (PASAT), in which information processing speed can be manipulated by varying the presentation speed of stimuli. Results: MS patients with low education performed worse than healthy controls at faster PASAT speeds. By contrast, no difference was observed between MS patients with high education and matched healthy controls, regardless of PASAT speed. Moreover, we found that neither occupational attainment nor perceived fatigue has an influence on MS patients' cognitive performance. Conclusion: These findings provide evidence that higher education could be protective against MS-associated cognitive deficits and that high speed PASAT versions are more suitable for identifying compensatory capacities compared to low speed PASAT versions. [ABSTRACT FROM AUTHOR]

Quantum photonic integration circuits are a promising approach to scalable quantum processing with photons. Waveguide single-photon-detectors (WSPDs) based on superconducting nanowires have been recently shown to be compatible with single-photon sources for a monolithic integration. While standard WSPDs offer single-photon sensitivity, more complex superconducting nanowire structures can be configured to have photon-number-resolving capability. In this work, we present waveguide photon-number-resolving detectors (WPNRDs) on GaAs/Al0.75Ga0.25As ridge waveguides based on a series connection of nanowires. The detection of 0-4 photons has been demonstrated with a four-wire WPNRD, having a single electrical read-out. A device quantum efficiency of ∼24% is reported at 1310 nm for the transverse electric polarization. [ABSTRACT FROM AUTHOR]

The incidence of depression in diabetic patients is quite high; moreover, it has been suggested that the presence of depression itself may increase the risk of diabetes mellitus. Hence, it follows that the simultaneous use of antidiabetic and antidepressant drugs is common. Some clinical evidence indicates that selective serotonin re-uptake inhibitors (SSRIs) could be very useful in treating overweight patients, both with and without diabetes. However, recent deregulation of glucidic metabolism was tested in diabetic subjects treated with antidepressants. Several cases of hyperglycaemia and hypoglycaemia associated with other SSRIs have been published, whereas only one case of escitalopram inducing hyperglycaemia has been noted. The exact mechanism of glucose control impairment in patients taking SSRIs--escitalopram in particular--still remains unclear. We describe a diabetic 83-year-old woman with good glycaemic control (as evinced by glycaemic and glycosylated haemoglobin assay--HbAlc--values) before escitalopram initiation in response to therapy with glibenclamide. Escitalopram resulted in a significantly increased glycaemia values 5 days following administration. Glycaemia values returned to normality only after suspension of escitalopram, despite antidiabetic dosage increase. We report this case to draw attention to escitalopram as a possible cause of glycaemic control loss. [ABSTRACT FROM AUTHOR]

We studied surface plasmon sensors based on micrometric metal meshes by optical transmission spectroscopy as a function of the angle of incidence. The mesh period was set to 2 μm for operation at mid-infrared wavelengths. Metal meshes on dielectric substrates were compared to suspended meshes obtained with a lift-off-free fabrication process, which reduces plasmon damping and increases the quality factor up to 25. We have numerically calculated the electric field distribution of 'dark' quadrupole-like modes and found that the suspended mesh provides an enhanced interaction volume extending up to hundreds of nanometers in free space. Our sensors have been experimentally tested and they exhibited a sensitivity up to 1.4 · 10 nm, at least 1 order of magnitude better than standard mid-infrared absorption spectroscopy. [ABSTRACT FROM AUTHOR]

The study evaluates the possible relations between cognitive impairment, persisting anosognosia for hemiplegia and peripersonal neglect. Thirty eight chronic right hemisphere stroke patients were divided in three age- and education-matched groups: A (n = 13) patients with left hemiparesis, peripersonal neglect, and anosognosia for hemiplegia; B (n = 12) patients with left hemiparesis and peripersonal neglect, and C (n = 13) patients with left hemiparesis only. We used MMSE and WAIS Verbal IQ and verbal subtests to assess cognitive impairment in patients, in order to avoid a bias due to visuospatial deficit, which is common in patients with neglect. VIQ, Information, Digit Span and Vocabulary WAIS subtests as well as MMSE were found to be significantly lower in group A versus group B. No difference was found in any test between groups B and C, indicating a general worse cognition in patients compared to those without anosognosia for hemiplegia. Patients with anosognosia for hemiplegia also showed larger brain lesions and, more frequently, frontal, parietal, temporal and basal ganglia involvement, particularly if they had low verbal IQ, indicating a relationship between cognitive impairment, persisting anosognosia for hemiplegia and large right hemisphere lesions. [ABSTRACT FROM PUBLISHER]

The recent progress in the nanofabrication of superconducting films opens the road toward detectors with highly improved performances. This is the case for superconducting nano-striplines where the thickness and the width are pushed down to the extreme limits to realize detectors with unprecedented sensitivity and ultra fast response time. In this way quantum detectors for single photons at telecommunication wavelengths and for macromolecules such as proteins can be realized. As is often the case in applied nanotechnology, it is a challenge to make devices with the necessary macroscopic dimensions that are needed to interface present technologies, while maintaining the performance improvements. For nano-stripline detectors, both the fast temporal response and the device sensitivity is generally degraded when the area is increased. Here, we present how such detectors can be scaled up to macroscopic dimensions without losing the performance of the nano-structured active elements by using an innovative configuration. In order to realize ultrathin superconducting film the nano-layer is growth with a careful setup of the deposition technique which guarantees high quality and thickness uniformity at the nano-scale size. The active nano-strips are defined with the state-of-the-art electron beam nanolithography to achieve a highly uniform linewidth. We present working detectors based on nano-strips with thicknesses 9-40 nm and widths of 100-1000 nm which exhibit unprecedented speed and area coverage (40 × 40 μm for single photon detectors and 1 × 1 mm for single molecule detectors) based on niobium nitride thus enabling practical use of this nanotechnology. [ABSTRACT FROM AUTHOR]

The fluoropyrimidines are commonly used in chemotherapeutic cancer medicine, but many patients still experience severe adverse side effects from these drugs. We observed a severe toxicity in a 50-year-old woman treated with capecitabine and docetaxel for a metastatic breast cancer. Since dihydropyrimidine dehydrogenase (DPD) is the main candidate for pharmacogenetic studies on 5-FU toxicity, the entire coding sequence and exon-flanking intronic regions of the DPYD gene were sequenced in the patient. None of the previously described deleterious variants were detected. Also, the haplotype-based analysis failed to reveal DPYD variations associated with 5-FU toxicity. We also evaluated the UH2/U ratio in plasma as an index of 5-FU pharmacokinetics. The UH2/U value did not demonstrate low DPD activity in the patient. We discuss the advantages and limitations of this approach, particularly concerning the clinical applications of 5-FU pharmacogenetics in the family setting. [ABSTRACT FROM AUTHOR]

We report on the fabrication and optical properties of thin metal films periodically patterned with square hole arrays of 2 micron pitch, which behave as substrateless plasmonic devices at mid-infrared frequencies. Large (3×3 mm) meshes were fabricated by metallizing a patterned silicon nitride membrane. The mid-infrared spectra display resonant absorption lines with a Q-factor up to 22 in both transmission and reflection, due to the interaction of the radiation with surface plasmon modes on both faces of the film, allowed by substrate removal. The devices can be used to fabricate surface plasmon-based chemical sensors employing mid-infrared radiation. [ABSTRACT FROM AUTHOR]

Neuropsychological impairment affects 40-65% of multiple sclerosis patients, mainly involving speed in information processing, attention, executive functions and memory. Deterioration occurs over time independently from disability and seems to correlate particularly with magnetic resonance imaging (MRI) atrophy measures. Studies on therapies effective in controlling cognitive impairment are scanty. We found that intensive and specific training of attention, information processing and executive functions is significantly effective in ameliorating both neuropsychological treated functions and in reducing depression. Preliminary functional MRI data suggest that possible neural correlates of this neuropsychological training could be an exercise-induced activation of prefrontal and cingulate cortices. [ABSTRACT FROM AUTHOR]

The progress in nanofabrication has made possible the realization of optic nanodevices able to handle single photons and to exploit the quantum nature of single-photon states. In particular, quantum cryptography (or more precisely quantum key distribution, QKD) allows unconditionally secure exchange of cryptographic keys by the transmission of optical pulses each containing no more than one photon. Additionally, the coherent control of excitonic and photonic qubits is a major step forward in the field of solid-state cavity quantum electrodynamics, with potential applications in quantum computing. Here, we describe devices for realization of single photon generation and detection based on high resolution technologies and their physical properties. Particular attention will be devoted to the description of single-quantum dot sources based on photonic crystal microcavites optically and electrically driven: the electrically driven devices is an important result towards the realization of single photon source “on demand”. A new class of single photon detectors, based on superconducting nanowires, the superconducting single-photon detectors (SSPDs) are also introduced: the fabrication techniques and the design proposed to obtain large area coverage and photon number-resolving capability are described. [ABSTRACT FROM AUTHOR]

Superconducting devices based on the Josephson effect are effectively used for the implementation of qubits and quantum gates. The manipulation of superconducting qubits is generally performed by using microwave pulses with frequencies from 5 to 15 GHz, obtaining a typical operating frequency from 100MHz to 1 GHz. A manipulation based on simple pulses in the absence of microwaves is also possible. In our system, a magnetic flux pulse modifies the potential of a double SQUID qubit from a symmetric double well to a single deep-well condition. By using this scheme with a Nb/AlOx/Nb system, we obtained coherent oscillations with sub-nanosecond period (tunable from 50 to 200 ps), very fast with respect to other manipulating procedures, and with a coherence time up to 10 ns, of the order of that obtained with similar devices and technologies but using microwave manipulation. We introduce ultrafast manipulation, presenting experimental results, new issues related to this approach (such as the use of a compensation procedure for canceling the effect of 'slow' fluctuations) and open perspectives, such as the possible use of RSFQ logic for qubit control. [ABSTRACT FROM AUTHOR]

Amphibians and reptiles were surveyed at several rainforest sites on the Tsaratanana Massif and in the nearby Manongarivo Massif, NW Madagascar. Visual methods and pitfalls led to the discovery of 30 amphibian and 23 reptile species at Tsaratanana, and 30 amphibian and 17 reptile species at Manongarivo. The herpetofauna present at the investigated sites turned out to be composed (1) of typical elements of Madagascar's eastern rainforests, (2) of species widely distributed at low altitudes of the northwest, (3) of species typical for rainforests of the northeast and north (Montagne d'Ambre), and (4) of a rather large proportion of possible endemics. Beside many still undescribed species, we found some species of considerable biogeographic interest, such as the snake Pseudoxyrhopus ambreensis and the treefrog Boophis blommersae at Tsaratanana, previously known only from Montagne d'Ambre, which emphasizes a biogeographical link to this northernmost massif. At Manongarivo we also found one still unidentified species of leaf-axil dwelling mantellid frog of the subgenus Pandanusicola, representing the first record of this subgenus from northwestern rainforests. Comparisons of mitochondrial DNA sequences of some selected amphibian species indicate that the populations from Tsaratanana and Manongarivo show no or only a slight differentiation between the two massifs but are often strongly different from conspecific populations, or from their closest relatives, in other regions of Madagascar. Conservation at Tsaratanana should, as a priority, include an increase of field surveys and an integration of local people in the management planning of this huge massif. [ABSTRACT FROM AUTHOR]

We present a new photon number resolving detector (PNR), the Parallel Nanowire Detector (PND), which uses spatial multiplexing on a subwavelength scale to provide a single electrical output proportional to the photon number. The basic structure of the PND is the parallel connection of several NbN superconducting nanowires (≈100 nm wide, few nm thick), folded in a meander pattern. Electrical and optical equivalents of the device were developed in order to gain insight on its working principle. PNDs were fabricated on 3-4 nm thick NbN films grown on sapphire (substrate temperature TS = 900°C) or MgO (TS = 400°C) substrates by reactive magnetron sputtering in an Ar/N2 gas mixture. The device performance was characterized in terms of speed and sensitivity. The photoresponse shows a full width at half maximum (FWHM) as low as 660 ps. PNDs showed counting performance at 80 MHz repetition rate. Building the histograms of the photoresponse peak, no multiplication noise buildup is observable and a one-photon quantum efficiency can be estimated to be η ∼ 3% (at 700 nm wavelength and 4.2 K temperature). The PND significantly outperforms existing PNR detectors in terms of simplicity, sensitivity, speed, and multiplication noise. [ABSTRACT FROM AUTHOR]

We report on the fabrication and characterization of high performance nanowire superconducting single photon detectors (SSPD) on MgO substrates. The deposition of the superconducting material (NbN) has been performed by magnetron sputtering at 400°C. This deposition temperature is low enough to be compatible with the fabrication on traditional optical materials like GaAs. First, SSPD meanders covering a surface of 5 × 5 µm2 were characterized. We measured quantum efficiencies up to 20% at 1300 nm. Then, we used a straight 250 µm-long NbN nanowire to perform a spatially resolved measurement of the efficiency. Both efficiency dips and peaks were observed. The dips were correlated to lithographic defects, as confirmed by scanning electron microscopy. Conversely, no evidence of a lithographic origin of efficiency peaks was found. [ABSTRACT FROM AUTHOR]

A reliable marking technique was needed for a mark–release–recapture experiment with adults of Diabrotica speciosa (Germar). Four marking techniques, acrylic paint (spattered or brushed on the surface of the insect); and fluorescent pigments (dusted on surfaces or mixed with diet to produce an ingested marker), were tested. Fluorescent pigment durability for the dusting and ingested techniques was evaluated for laboratory conditions and under simulated field conditions. The impact of the techniques on beetle survival was also assessed. Both acrylic paint techniques caused mobility problems in the beetles, and neither technique lasted for more than 48 h. Both fluorescent pigment techniques were more reliable, but the dusting technique showed a significantly higher mortality than the control, and duration variations between laboratory and field conditions. Use of fluorescent pigments added to the diet was the most reliable technique. This technique allowed the manipulation of the marking period, and provided reliable timing of marker persistence in the field. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to estimate basal energy expenditure and variation in anthropometrics and body composition parameters after dietetic and lifestyle treatment in a population of obese untreated obstructive sleep apnea syndrome (OSAS) patients. Patients and methods: Sixteen obese mild to moderate untreated OSAS patients (AHI 5-29)followed a program of dietetic lifestyle and weight management. Body composition, anthropometric measures, indirect calorimetry, blood analysis, and results of the questionnaire for the Stanford Sleepiness Scale (SSS) were recorded with follow-up at 3 months. Results: Eleven patients completed the study. Weight (p = 0.001), body mass index (BMI) (p = 0.001), neck circumference (p = 0.003),fat mass (FM) (p = 0.036), and resting metabolic rate (RMR) (p = 0.008) also in connection with FM (p = 0.008) showed meaningful associations. Multivariate associations between weight and neck circumference (p = 0.025), weight and SSS score (p = 0.001), and RMR and FFM loss (p = 0.019) were also noted. Respiratory quotient was unvaried. Conclusion: The results of our study, in agreement with those of other works, confirm the importance of weight decrease for OSAS therapy. A significant association between weight loss and sympto.matology estimated with SSS was observed, mainly in relation to the circumference of the neck. These data confirm the hypothesis that one of the main pathogenetic factors of nocturnal apneas in obese patients is the deposition of adipose tissue around the upper airway. The massive reduction in RMR was one of the reasons management of weight loss in OSAS patients is complicated. Why RMR decrease is not related to a decrease of FFM and possible alterations of lipid metabolism in OSAS patients should be analyzed further in other studies. [ABSTRACT FROM AUTHOR]

Toxic baits and traps for Diabroticina, based on bitter cucurbit extracts, have been utilized for a number of years with inconsistent results. Four species of bitter Cucurbitaceae were compared in the field for their attractancy to species of Diabroticina in Argentina and the United States. The comparisons were made with polyester fabrics treated with known volumes of different cucurbit extracts, against a standard cucurbit extract of bitter Hawkesbury watermelon ( Citrullus lanatus (Thunberg) Matsumura and Nakai). The factors evaluated were: the attractancy of the different extracts in terms of beetle numbers, species and sex of the Diabroticina caught; influence of different fabrics on such attraction; and influence of several weather variables on the catches. The most attractive species was Cayaponia bonariensis (Miller) Martinez Crovetto, however, practical considerations indicated that Cucumis myriocarpus Naudin and Hawkesbury watermelon may be better choices from the commercial perspective. No single weather factor could explain the catches throughout the sample range, but different temperature and barometric pressure ranges provided some predictive value. Although the susceptibility to weather conditions and a strong male dominance in the catches raise the question of the usefulness of cucurbitacins as the main component in toxic baits or traps, these drawbacks may prove to be less important in widespread bait applications and Diabroticina management in vegetable crops. [ABSTRACT FROM AUTHOR]

We report on experiments performed on a system consisting of a double SQUID (Superconducting Quantum Interference Device) built with gradiometer geometry. Two single-turn coils provide two independent control fluxes: one of these allows biasing the device and tilting the potential, while the other changes the barrier height of the potential. When the dynamics of the inner dc SQUID can be neglected, the free energy of the double SQUID, as a function of the internal magnetic flux, is just the corrugated parabola of an rf SQUID whose local minima represent metastable states for the system. Our analysis instead is substantially concerned with the interesting phenomenology generated by the static configurations of an internal two-junction interferometer and by the tunability of the internal loop inductance. Two readout systems are employed to thoroughly characterize the dynamics of our system. We investigate the dynamical response at temperatures low enough (tens of mK) to minimize the effects of thermal fluctuations concentrating the analysis on the aspects that could be relevant for macroscopic quantum coherence and computing. The results indicate that from the finite inductance of the inner loop originates a potential well generating competing processes with the tunneling between the two main wells of the rf-SQUID potential. [ABSTRACT FROM AUTHOR]

3,3′-Dimethoxybenzidine (DMB), a congener of benzidine used in the dye industry and previously found to be carcinogenic in rats, was evaluated for its genotoxic activity in primary cultures of rat and human hepatocytes and of cells from human urinary bladder mucosa, as well as in liver and bladder mucosa of intact rats. A similar modest dose-dependent frequency of DNA fragmentation was revealed by the alkaline elution technique in metabolically competent primary cultures of both rat and human hepatocytes exposed for 20 h to subtoxic DMB concentrations ranging from 56 to 180 μM. Replicating rat hepatocytes displayed a modest increase in the frequency of micronucleated cells after a 48-h exposure to 100 and 180 μM concentrations. In primary cultures of human urinary bladder mucosa cells exposed for 20 h to 100 and 180 μM DMB, the Comet assay revealed a clear-cut increase of DNA fragmentation. In rats given one-half LD50 of DMB as a single oral dose, the GSH level was reduced in both the liver and urinary bladder mucosa, whereas DNA fragmentation was detected only in the bladder mucosa. Taken as a whole, these results suggest that DMB should be considered a potentially genotoxic chemical in both rats and humans; the selective effect on the rat urinary bladder might be the consequence of pharmacokinetic behavior. [ABSTRACT FROM PUBLISHER]