Morphological and Optical Characterization of Gold Nanoparticles Decorated Porous Silicon.

In this article, physical characteristics of porous silicon (PS) obtained by electro chemical etching using HAuCl4 in the electrolyte are described. The morphological and optical features of PS decorated with gold-nanoparticles (AuNPs) were analyzed in function of the chemical etching time. The insertion of AuNPs inside the PS were performed simultaneously with the formation of the porous silicon layer. Scanning electron microscopy (SEM) analysis showed the formation and incorporation of AuNPs with an average size of 20 nm in the PS structure, which has a pore size of 1.5 µm. Also, it was possible to observe the loss of Si in function of the etching time. Photoluminescence spectroscopy analysis shows a decreasing of the PL intensity, which can be related to the presence of oxygen in the samples. Raman spectroscopy was used to estimate the size of the Si nanocrystals in the PS structure, which suffers a reduction in size due to the presence of HAuCl4 in the electrolyte.

Mimicking physiological O2 tension in the female reproductive tract improves assisted reproduction outcomes in pig.

STUDY QUESTION: Is O2 tension in the pig oviduct and uterus affected by the estrous cycle stage and the animal's age, and can the outcome of in vitro embryo development be improved by mimicking these physiological values? SUMMARY ANSWER: O2 tension within the pig reproductive organs is affected by the animal's age, and values close to those measured in vivo have a positive impact on embryo development and quality when used during IVF and embryo culture (EC). WHAT IS KNOWN ALREADY: To obtain a healthy embryo in vitro, it is necessary to adopt a culture microenvironment that approximates physiological conditions. Despite advances in surgical procedures and sensitive probes that allow accurate assessment of in vivo O2 tension, few such studies have been conducted recently in mammals. In addition, no reference values of physiological O2 tension in the reproductive tract exist for large animal models such as pig, and the effect of O2 tension on ART outcomes is unknown. STUDY DESIGN, SIZE, DURATION: This study was conducted in pigs. We measured oviductal and uterine O2 tension (n = 29 and 13, respectively) and then examined how the use of the physiological values in pig IVF and EC affected pig ART output (n = 1447 oocytes). PARTICIPANTS/MATERIALS, SETTING, METHODS: The oviductal and uterine O2 tension at the different stages of the estrous cycle was monitored using a laparo-endoscopic single-site surgery (LESS) assisted approach along with a flexible and thin miniaturized luminescent probe. Two groups of pigs, Large-white × Landrace breed, were used: for the first group, 16 pre-pubertal gilts (5 months old and 95 kg) were induced to ovulate with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG); in the second group 13 mature sows (24-48 months and 185 kg) were used. IVF and EC were performed at two different O2 tensions: Atmospheric O2 (20%) and the mean in vivo value measured (7%). At 18-20 h post-insemination (hpi), a small sample of presumptive zygotes were fixed, stained and examined under epifluorescence microscopy to assess the fertilization rates. At 48 hpi, cleavage was evaluated under the stereomicroscope. Finally, at 180 hpi, development to the blastocyst stage was quantified, blastocyst morphology was assessed, and embryos were fixed and stained to count the mean cell number per blastocyst. MAIN RESULTS AND THE ROLE OF CHANCE: The mean O2 content within the pig oviduct and uterus was always lower than in ambient air. The average O2 percentage was higher in gilts (10.0%) than in sows (7.6%) (P < 0.0001). The cleavage rate of porcine in vitro fertilized embryos maintained under 7% O2 during IVF and EC was significantly higher (60.0 ± 2.3) compared with those cultured under 20% O2 (32.0 ± 2.2) (P < 0.05). An increase in the number of cells in embryos cultured under the low O2 concentration (88.9 ± 5.9) was observed compared to those cultured under 20% O2 (59.0 ± 5.0) (P < 0.05). LARGE SCALE DATA: None. LIMITATIONS, REASONS FOR CAUTION: Although minimally invasive surgery was used the effect of anesthesia and manipulations on O2 tension within the organs are unknown. WIDER IMPLICATIONS OF THE FINDINGS: Using physiological oxygen concentrations in IVF/EC could improve ART outcomes. STUDY FUNDING AND COMPETING INTEREST(S): This study was funded by Spanish Ministry of Economy and Competitiveness (MINECO) and European Regional Development Fund (FEDER). Grants AGL2012-40180-C03-01 and AGL2015-66341-R. The authors declare no conflict of interest.

Recommendations for the prevention and diagnosis of asthma in children: Evidence from international guidelines adapted for Mexico.

BACKGROUND: With the availability of high-quality asthma guidelines worldwide, one possible approach of developing a valid guideline, without re-working the evidence, already analysed by major guidelines, is the ADAPTE approach, as was used for the development of National Guidelines on asthma. METHODS: The guidelines development group (GDG) covered a broad range of experts from medical specialities, primary care physicians and methodologists. The core group of the GDG searched the literature for asthma guidelines 2005 onward, and analysed the 11 best guidelines with AGREE-II to select three mother guidelines. Key clinical questions were formulated covering each step of the asthma management. RESULTS: The selected mother guidelines are British Thoracic Society (BTS), GINA and GEMA 2015. Responses to the questions were formulated according to the evidence in the mother guidelines. Recommendations or suggestions were made for asthma treatment in Mexico by the core group, and adjusted during several rounds of a Delphi process, taking into account: 1. Evidence; 2. Safety; 3. Cost; 4. Patient preference - all these set against the background of the local reality. Here the detailed analysis of the evidence present in BTS/GINA/GEMA sections on prevention and diagnosis in paediatric asthma are presented for three age-groups: children with asthma ≤5 years, 6-11 years and ≥12 years. CONCLUSIONS: For the prevention and diagnosis sections, applying the AGREE-II method is useful to develop a scientifically-sustained document, adjusted to the local reality per country, as is the Mexican Guideline on Asthma.

On the origins of anomalous elastic moduli and failure strains of GaP nanowires.

Previous reports suggest that Raman peaks in uniaxially loaded nanowires with diamond cubic and zinc blende crystal structures shift at rates that are significantly different from bulk specimens. We have investigated the first order Raman scattering from individual, free-standing, [111] oriented GaP nanowires ranging from 75 to 180 nm in diameter at uniaxial tensile stresses up to 5 GPa. All of the phonon modes were shifted to frequencies lower than previously reported for bulk GaP, and significant splitting of the degenerate transverse optical mode was observed. A general analysis method using single and double Lorentzian fits of the Raman peaks is presented and used to report more accurate values of the phonon deformation potentials (PDPs) that relate uniaxial strains to Raman peak shifts in GaP. A new set of PDPs determined from the nanowires revealed that the they have elastic moduli and failure strains that are consistent with bulk GaP. The analysis method eliminated the anomalous, inconsistent deformation behavior commonly reported in Raman-based strain measurements of nanowires, and can be extended to other materials systems with degenerate phonons.

Magneto-conductivity and magnetically-controlled nonlinear optical transmittance in multi-wall carbon nanotubes.

The impact of vectorial magnetic field effects on electrical conductivity and nonlinear optical transmittance exhibited by multi-wall carbon nanotubes was studied. The samples were synthetized by an aerosol pyrolysis processing route in a thin film form. Optical signals in a two-wave mixing configuration allowed us to identify two orthogonal directions of propagation for a magnetic field travelling through the nanomaterials studied. A selective modification in optical absorption was considered to be induced by magnetic perturbations in the sample. Standard optical Kerr gate measurements were carried out for exploring the third order nonlinear optical behavior of the film. A capacitive effect influenced by optical and magnetic excitations was distinguished to be characteristic of the sample. Magneto-quantum conductivity sensitive to the direction of an external magnetic field interacting with the tubes was analyzed. Magnetically-induced changes in electronic band parameters seem to be the main responsible for the optical and electrical modulation observed in the nanostructures. Immediate applications for developing magneto-optical and magneto-electrical functions can be contemplated.

Effect of Supplemental Corn Dried Distillers Grains with Solubles Fed to Beef Steers Grazing Native Rangeland during the Forage Dormant Season.

Two experiments were conducted to evaluate the effects of the level of corn dry distillers grains with solubles (CDDGS) supplementation on growing performance, blood metabolites, digestion characteristics and ruminal fermentation patterns in steers grazing dormant forage. In Exp. 1, of growth performance, 120 steers (204±5 kg initial body weight [BW]) were distributed randomly into 3 groups (each of 40 steers), which were provided with the following levels of CDDGS supplement: 0%, 0.25%, or 0.50% BW. All groups of steers were grazed for 30 days in each of 3 grazing periods (March, April, and May). Approximately 1,000 ha of the land was divided with electric fencing into 3 equally sized pastures (333 ha in size). Blood samples were collected monthly from 20 steers in each grazing group for analysis of glucose (G), urea-nitrogen (UN) and non-esterified fatty acids. Final BW, average daily gain (ADG) and supplement conversion (CDDGS-C) increased with increasing levels of CDDGS supplementation (p<0.05).The CDDGS supplementation also increased the plasma G and UN concentrations (p<0.05). In Exp. 2, of digestive metabolism, 9 ruminally cannulated steers (BW = 350±3 kg) were distributed, following a completely randomized design, into groups of three in each pasture. The ruminally cannulated steers were provided the same levels of CDDGS supplementation as in the growing performance study (0%, 0.25%, and 0.50% BW), and they grazed along with the other 40 steers throughout the grazing periods. The dry matter intake, crude protein intake, neutral detergent fiber intake (NDFI), apparent digestibility of dry matter (ADDM), crude protein (ADCP) and neutral detergent fiber (ADNDF) increased with increasing levels of CDDGS supplementation (p<0.05). The ruminal degradation rates of CP (kdCP), NDF (kdNDF) and passage rate (kp) also increased with increasing levels of CDDGS supplementation (p<0.05). Ruminal ammonia nitrogen (NH3-N) and propionate concentrations also increased with increasing levels of CDDGS supplementation (p<0.05). However, acetate concentrations decreased with increasing levels of CDDGS supplementation (p<0.05). Liquid dilution rate increased with increasing levels of CDDGS supplementation but ruminal liquid volume decreased (p<0.05). On the basis of these findings, we can conclude that CDDGS supplementation enhanced the productive performance of cattle grazing native rangeland without negatively affecting forage intake, glucose and urea-nitrogen blood concentrations, ruminal degradation and ruminal fermentation patterns.

[Translated article] Experience in major complications with total trapezometacarpal prostheses.

INTRODUCTION: The treatment of rhizarthrosis using trapeziometacarpal prostheses (TMP) is increasing. Complications may lead to loss of the implant and result in salvage surgery. Our aim was to assess major complications with the use of some TMP models and their rescue. MATERIAL AND METHOD: Retrospective study on TMP implanted between 2006 and 2021. Models studied: Arpe®, Elektra®, Ivory®, Maïa®, Isis® and Touch®. Demographic data were assessed, implant placement by radiographic study, technical data, complications, salvage surgeries and final survival. RESULTS: Review of 224 TMP, 45 Arpe® (95.5% survival, rate follow-up [R] 6-16 years), 5 Elektra® (80% survival, R 13-14), 14 Ivory® (92.8% survival, R 9-11), 7 Maïa® (100% survival, R 8-9), 115 Isis® (99.1% survival, R 1-8), 38 Touch® (100% survival, R 1-4). The medial angle of the dome with the proximal articular surface of the trapezium in the lateral plane, was: Arpe®: 8.85°, Elektra®: not assessable, Ivory®: 6.6°, Maïa®: 14.4°, Isis®: 3.8°, and Touch®: 5.95°. The Isis® was placed 100% with scopic guidance presenting a significantly lower angle respect to the medial angle of the dome with the proximal articular surface of the trapezium. As main complications, we observed 3.5% of dislocations and 4% of mobilisations, with the Elektra® being responsible for 47% of these. Nineteen salvage surgeries were performed, with 3% of the implants being lost. CONCLUSIONS: Dislocation and mobilisation are the most observed complications, the Elektra® responsible for almost half of them. Correct placement and implant design appear to be crucial to avoid them in the short and long term.

In health and illness: does taste remain consistent? Exploring the influence of inflammation on taste perception through a systematic review and meta-analysis.

OBJECTIVE: Dysgeusia is characterized by a loss of taste perception, leading to malnutrition. This situation affects inflammatory conditions such as respiratory and neurological conditions, obesity, cancer, chemotherapy, aging, and many others. To date, there is not much information on the prevalence and risk of dysgeusia in an inflammatory condition; also, it is unclear which flavor is altered. MATERIALS AND METHODS: We systematically searched three databases from January 2018 to January 2023. Participants were children, adults, or elderly persons with an inflammatory condition and evaluated taste loss. A random effects model was used for statistical analysis to calculate the pooled odds ratio with its corresponding 95.0% confidence interval to estimate the probability of taste alteration (dysgeusia) in an inflammatory condition. RESULTS: The data allowed us to conduct a systematic review, including 63 original articles and 15 studies to perform the meta-analysis. The meta-analysis indicated a heterogenicity of 84.7% with an odds ratio of 3.25 (2.66-3.96), indicating a significant risk of Alzheimer's disease, SARS-CoV-2, chemotherapy, and rhinosinusitis. CONCLUSIONS: Inflammatory conditions and taste alterations are linked. Dysgeusia is associated with a higher risk of malnutrition and poorer general health status, especially in vulnerable populations.

Optoelectronic modulation by multi-wall carbon nanotubes.

We report the observation of photoconduction and a strong nonlinear optical absorptive response exhibited by multi-wall carbon nanotubes. An aerosol pyrolysis method was employed for the preparation of the samples. Measurements of the optical transmittance with 7 ns pulses at 1064 nm wavelength allowed us to identify a two-photon absorption effect as the main mechanism of third-order nonlinearity. Photoconductive experiments at 445 nm wavelength seem to confirm the possibility for generating non-resonant multi-photonic absorption processes in the multi-wall carbon nanotubes. By the optical control of the conductivity in the nanotubes, we implement an optoelectronic amplitude modulator device with potential applications for sharp selective functionalities.

Evaluation of biocidal efficacy of copper alloy coatings in comparison with solid metal surfaces: generation of organic copper phosphate nanoflowers.

AIMS: To analyse the biocidal efficacy of thermal sprayed copper surfaces. METHODS AND RESULTS: Copper alloy sheet metals containing >60% copper have been shown to exhibit potent biocidal activity. Surface biocidal activity was assessed by epifluorescence microscopy. After 2-h exposure at 20 °C in phosphate-buffered saline (PBS), contact killing of Gram-negative Escherichia coli and Gram-positive Staphylococcus epidermidis by brass sheet metal and phosphor bronze was 3-4-times higher than that by stainless steel. SEM observations revealed that the surface membranes of both bacterial strains were slightly more irregular when exposed to brass sheet metal than stainless steel. However, when exposed to phosphor bronze coating, E. coli were 3-4 times larger with irregular membrane morphology. In addition, the majority of the cells were associated with spherical carbon-copper-phosphate crystalline nanostructures characteristic of nanoflowers. The membranes of many of the S. epidermidis exhibited blebbing, and a small subset was also associated with nanoflowers. CONCLUSIONS: Our data indicate that increasing the surface roughness of copper alloys had a pronounced impact on the membrane integrity of Gram-positive and, to a lesser degree, Gram-negative bacteria. In the presence of PBS, carbon-copper-phosphate-containing nanoflowers were formed, likely nucleated by components derived from killed bacteria. The intimate association of the bacteria with the nanoflowers and phosphor bronze coating likely contributed to their nonreversible adhesion. SIGNIFICANCE AND IMPACT OF THE STUDY: Thermal spraying of copper alloys provides a strategy for the rapid coating of three-dimensional organic and inorganic surfaces with biocidal copper alloys. Our study demonstrates that the macroscale surface roughness generated by the thermal spray process enhances the biocidal activity of copper alloys compared with the nanoscale surface roughness of copper sheet metals. Moreover, the coating surface topography provides conditions for the rapid formation of organic copper phosphate nanocrystals/nanoflowers.

Experience in major complications with total trapezometacarpal prostheses. / Experiencia en complicaciones mayores con las prótesis totales trapeciometacarpianas.

INTRODUCTION: The treatment of rhizarthrosis using trapeziometacarpal prostheses (TMP) is increasing. Complications may lead to loss of the implant and result in salvage surgery. Our aim was to assess major complications with the use of some TMP models and their rescue. MATERIAL AND METHOD: Retrospective study on TMP implanted between 2006 and 2021. Models studied: Arpe®, Elektra®, Ivory®, Maïa®, Isis® and Touch®. Demographic data were assessed, implant placement by radiographic study, technical data, complications, salvage surgeries and final survival. RESULTS: Review of 224 TMP, 45 Arpe® (95.5% survival, rate follow-up [R] 6-16 years), 5 Elektra® (80% survival, R 13-14), 14 Ivory® (92.8% survival, R 9-11), 7 Maïa® (100% survival, R 8-9), 115 Isis® (99.1% survival, R 1-8), 38 Touch® (100% survival, R 1-4). The medial angle of the dome with the proximal articular surface of the trapezium in the lateral plane, was: Arpe®: 8.85°, Elektra®: not assessable, Ivory®: 6.6°, Maïa®: 14.4°, Isis®: 3.8°, and Touch®: 5.95°. The Isis® was placed 100% with scopic guidance presenting a significantly lower angle respect to the medial angle of the dome with the proximal articular surface of the trapezium. As main complications, we observed 3.5% of dislocations and 4% of mobilisations, with the Elektra® being responsible for 47% of these. Nineteen salvage surgeries were performed, with 3% of the implants being lost. CONCLUSIONS: Dislocation and mobilisation are the most observed complications, the Elektra® responsible for almost half of them. Correct placement and implant design appear to be crucial to avoid them in the short and long term.

Screws versus plate with screws for osteosynthesis of the posterior malleolus: a systematic review and meta-analysis.

INTRODUCTION: fractures involving the posterior malleolus (PM) of the ankle can have significant functional and clinical implications if not properly treated. The optimal treatment approach for these fractures remains uncertain. This review aims to compare the use of cannulated screws versus plate with screw fixation in terms of their impact on the development of postoperative ankle osteoarthritis and functional outcomes in patients with PM fractures. MATERIAL AND METHODS: a comprehensive search was conducted in PubMed, EMBASE, and Cochrane Library databases to identify studies directly comparing cannulated screws versus plate with screw fixation for PM fractures and their association with the development of postoperative osteoarthritis and functional outcomes. The quality of the included studies was assessed using appropriate assessment tools. The data on osteoarthritis development and functional outcomes were extracted and analyzed. RESULTS: a total of 691 articles were screened, and several studies were included for analysis. The findings revealed no statistically significant difference in the development of postoperative ankle osteoarthritis between the cannulated screws and plate with screw fixation groups. Similarly, there was no significant difference in functional outcomes between the two treatment approaches. CONCLUSION: based on the available evidence, there is no significant difference in the development of postoperative ankle osteoarthritis or functional outcomes between cannulated screws and plate with screw fixation for PM fractures. However, further research is needed to strengthen these findings and provide more conclusive evidence.

INTRODUCCIÓN: las fracturas que involucran el maléolo posterior (MP) del tobillo pueden tener importantes implicaciones funcionales y clínicas si no se tratan adecuadamente. El enfoque de tratamiento óptimo para estas fracturas sigue siendo incierto. El objetivo de esta revisión es comparar el uso de tornillos canulados versus placa con fijación de tornillos en cuanto a su impacto en el desarrollo de la osteoartrosis de tobillo postoperatoria y los resultados funcionales en pacientes con fracturas del MP. MATERIAL Y MÉTODOS: se realizó una búsqueda exhaustiva en las bases de datos de PubMed, EMBASE y Cochrane Library para identificar estudios que compararan directamente tornillos canulados versus placa con fijación de tornillos para fracturas de MP y su asociación con el desarrollo de osteoartrosis postoperatoria y los resultados funcionales. La calidad de los estudios incluidos se evaluó utilizando herramientas de evaluación adecuadas. Los datos sobre el desarrollo de osteoartrosis y los resultados funcionales se extrajeron y analizaron. RESULTADOS: se revisaron un total de 691 artículos y se incluyeron varios estudios para su análisis. Los hallazgos revelaron que no hay una diferencia estadísticamente significativa en el desarrollo de osteoartrosis de tobillo postoperatoria entre los grupos de tornillos canulados y placa con fijación de tornillos. Del mismo modo, no hubo una diferencia significativa en los resultados funcionales entre los dos enfoques de tratamiento. CONCLUSIÓN: según la evidencia disponible, no hay una diferencia significativa en el desarrollo de osteoartrosis de tobillo postoperatoria o en los resultados funcionales entre los tornillos canulados y la placa con fijación de tornillos para las fracturas del MP. Sin embargo, se necesita más investigación para fortalecer estos hallazgos y proporcionar evidencia más concluyente.

Angelman syndrome and thyroid dysfunction.

Angelman syndrome (AS) is a neurogenetic syndrome, has a prevalence of 1:10,000 to 1:40,000. Patients with AS have genetic alterations in maternal imprinting gene UB3A (15q11-q13) and molecular evaluations confirm the diagnosis. Our aim is to report a new case with AS and subclinical hypothyroidism (SCH) without goiter. Thyroid dysfunction has not been described as part of alterations in AS; the exact pathogenic mechanisms of SCH in patients with AS remains incompletely unknown.

The threshold tracking nerve conduction study technique: Experience of clinical users unfamiliar with a research-grade neuronal excitability system.

Objective: To 1) explore if clinical electrophysiologists with different degrees of experience performing standard nerve conduction studies could run a threshold tracking nerve conduction study (TTNCS) protocol and 2) learn how clinical users view a research-grade TTNCSs neuronal excitability system. Methods: Five clinical electrophysiologists conducted a TTNCS session using QTracS and then completed a questionnaire describing their impressions. Results: All of the electrophysiologists completed the QTracS protocol on an initial attempt. Perceived strengths comprised the ease of preparatory steps and quick protocol speed. Identified drawbacks included an unwieldly user-interface. The electrophysiologists indicated that knowledge of TTNCS principles and applications would be critical for incorporation of the method into clinical use. Conclusions: This pilot study suggests that clinical electrophysiologists can carry out TTNCSs with a research-grade system. The development of a more user-friendly program, along with dedicated education and training, could lead to wider application of the TTNCS technique. Significance: Considered together with clinical presentation and other biomarkers, increased use of TTNCSs could provide improved assessment of neuromuscular disease and treatment response.

Fast production of microwave component prototypes by additive manufacturing and copper coating.

We present a novel method for efficient production of prototypes of microwave components by fused depositing modeling, also known as 3D plastic printing, and vapor deposition coating of a 1 µm copper layer. We demonstrate that the properties of the components follow the predicted performance for low power microwave propagation. The production method offers new opportunities for cheap and efficient production of mock-ups and prototypes of advanced-geometry components for tests with low-power microwaves.

Initial survival of the Isis® total trapeziometacarpal prosthesis with conical trunk threaded cups. / Supervivencia inicial de la prótesis total trapeciometacarpiana de cúpula roscada Isis®.

INTRODUCTION: The treatment of trapeziometacarpal osteoarthritis through the implantation of total trapeziometacarpal prostheses is in continuous expansion. The Isis® prosthesis is a trunk-conical threaded anchorage prosthesis. Our objective was to assess the functional results and survival of this implant for at least one year of follow-up. MATERIAL AND METHOD: Prospective study on 53 Isis® prosthesis, implanted from april 2014 to january 2019. The Van Cappelle functional test, pain, strength, mobility, return to previous activity, radiological variables and placement of the trapezial component were evaluated. The surgical technique was performed with a guide wirefocused on the trapezius and control of the scopia. Observed complications were recorded and statistical analysis was performed. RESULTS: Fifty-one implants (49 patients) were reviewed. Mean follow-up was 2.1 years (1-5.7). Van Cappelle's test, pain, mobility, and grip and clamp strength improved significantly, as did the distance between the metacarpal head and the trapezius base; 96% of the patients returned in less than 6 months to their activities. Minor complications, 3 De Quervain's tendinopathy and 2 intra-operative metacarpal and 2 trapezium fractures were recorded, and one carpal tunnel syndrome. There was no dislocation, mobilization, or implant infection. CONCLUSIONS: The functional results of the Isis® prosthesis are excellent in the short term, far exceeding the first year of 100% of survival. The complications that arose were minor and few. The anchorage and placement of the trapezial component guided by scopia seem to be crucial for the good result.

Breteau Index threshold levels indicating risk for dengue transmission in areas with low Aedes infestation.

We used Breteau Indices to - retrospectively - predict dengue transmission. The presence of one house block (on average about 50 houses) with a Breteau Index >or=4 in a neighbourhood (a block plus the surrounding blocks in a radius of 100 m) predicted transmission at the latter level with 81.8% sensitivity and 73.3% specificity during the first month of the Havana 2001 dengue outbreak. This result corroborates the external validity of this threshold, at least in situations with low infestations levels.

Quantitative ultrasound of the tongue: Echo intensity is a potential biomarker of bulbar dysfunction in amyotrophic lateral sclerosis.

OBJECTIVES: To learn if quantitative ultrasound (QUS) distinguishes the tongues of healthy participants and amyotrophic lateral sclerosis (ALS) patients by echo intensity (EI) and to evaluate if EI correlates with measures of bulbar function. METHODS: Ultrasound was performed along the midline of the anterior tongue surface in 16 ALS patients and 16 age-matched controls using a linear hockey stick 16-7 MHz transducer. A region of interest was manually drawn and then EI was determined for the upper 1/3 of the muscle. For patients, the ALS functional rating scale - revised (ALSFRS-R) was used to calculate bulbar sub-scores and the Iowa Oral Performance Instrument (IOPI) was used to measure tongue strength. RESULTS: EI was significantly higher in ALS patients than in healthy participants (49.8 versus 37.8 arbitrary units, p < 0.01). In the patient group, EI was negatively correlated with ALSFRS-R bulbar sub-score (RS = -0.65, p < 0.01). An inverse correlation between EI and tongue strength did not reach significance (RS = -0.34, p = 0.28). CONCLUSIONS: This study suggests that EI can differentiate healthy from diseased tongue muscle, and correlates with a standard functional measure in ALS patients. SIGNIFICANCE: Tongue EI may represent a novel biomarker for bulbar dysfunction in ALS.

Probing individual quantum dots: noise in self-assembled systems.

In this work we explore the noise characteristics in lithographically-defined two terminal devices containing self-assembled InAs/InP quantum dots. The experimental ensemble of InAs dots show random telegraph noise (RTN) with tuneable relative amplitude-up to 150%-in well defined temperature and source-drain applied voltage ranges. Our numerical simulation indicates that the RTN signature correlates with a very low number of quantum dots acting as effective charge storage centres in the structure for a given applied voltage. The modulation in relative amplitude variation can thus be associated to the altered electrostatic potential profile around such centres and enhanced carrier scattering provided by a charged dot.