Binaural hearing with bone conduction stimulation

It has been argued that apparent masking-level differences (MLDs) in users of bilateral bone-anchored hearing aids (BAHAs) provide evidence of binaural hearing. However, there is considerably less acoustical isolation between the two ears with bone conduction (BC) compared to air conduction (AC). The apparent MLDs may have arisen, at least in part, from inter-cranial interference between signals arising from the two BAHAs (i.e. monaural effect). That might also explain some of the inter-individual variation in both the magnitude and the direction of the MLDs reported in BAHA users. The present study was composed of three experimental stages with the main aim to investigate the influence of interference in normal hearing participants by measuring masking level difference in AC and BC to explore the conditions contributing to the reported variation. An additional aim was to investigate the performance of a newly designed BC transducer; the balanced electromagnetic separation transducer (BEST), for bone conduction research as well as more general clinical use.Stage 1 evaluated the performance of the BEST in comparison to the clinically used RadioEar B71 in a series of acoustical (sensitivity and harmonic distortion) and psychoacoustical (hearing thresholds and vibrotactile thresholds) measurements. The results from these studies led to the use of the BEST in the second and third stages because they produced significantly lower harmonic distortion at low frequencies (mainly 250 Hz). The psychoacoustic measurements alluded to the need to use different calibration values with the BESTs.Stage 2 was a preliminary investigation comparing the MLDs with standard bilateral configurations between the AC and BC in nine normal-hearing participants. Signals were pure tones at one of three frequencies (250, 500, 1000 Hz), presented via AC or BC. Broadband noise (100- 5000 Hz) was always presented via AC at 70 dB SPL. Thresholds were estimated using a three-alternative forced choice procedure combined with an adaptive staircase. Transducers used were insert earphones and the BESTs for BC testing. The results from this stage showed a statistical significant difference between AC and BC MLDs at 250, 500 and 1000 Hz (mean difference is 9.4, 6.6 and 3.5 dB respectively). Evidence of the change in the MLDs direction is observed at 250 Hz in three participants.Stage 3 consisted of the investigation of inter-cranial interference in eighteen normal hearing participants. This stage was composed of three main measurements. The first measurement compared the AC and BC MLDs at three test frequencies. The second measurement evaluated the transcranial attenuation (TA). The third measurement was the novel feature of the study it evaluated the monaural interference effect through the measurement of the diotic and dichotic conditions in one test ear. A significant discrepancy was found between the AC and BC MLDs of approximately 6, 1.5 and 2.5 dB at 500, 1000 and 2000 Hz, respectively. The TA was found to be lower than 10 dB at the three test frequencies. Measurable MTLDs were reported in some of the participants, high inter-subject variability was observed in the direction of the MTLDs.The BEST can reliably replace the B71 in clinical setup. Formal adjustment of the reference equivalent threshold force levels is advised. Binaural hearing was achieved through bilateral BC stimulation to a lesser magnitude compared to AC MLDs in normal hearing participants. The discrepancy between the AC and BC MLDs was reduced with the increase in the frequency. The discrepancy can partially be explained by the cross-talk of the signal in one ear. The results showed that in some participants the magnitude of the monaural tone level difference was similar to the magnitude of the BC MLD. Further investigation is recommended to investigate the association of the transcranial delay with the discrepancy between the AC and BC MLDs. This investigation also recommends the investigation of the AC and BC MLDs in patients fitted with bilateral BAHAs

Thermal analysis of submicron nanocrystalline diamond films

The thermal properties of sub-μm nanocrystalline diamond films in the range of 0.37–1.1 μm grown by hot filament CVD, initiated by bias enhanced nucleation on a nm-thin Si-nucleation layer on various substrates, have been characterized by scanning thermal microscopy. After coalescence, the films have been outgrown with a columnar grain structure. The results indicate that even in the sub-μm range, the average thermal conductivity of these NCD films approaches 400 W m− 1 K− 1. By patterning the films into membranes and step-like mesas, the lateral component and the vertical component of the thermal conductivity, k<sub>lateral</sub> and k<sub>vertical</sub>, have been isolated showing an anisotropy between vertical conduction along the columns, with k<sub>vertical</sub> ≈ 1000 W m− 1 K− 1, and a weaker lateral conduction across the columns, with k<sub>lateral</sub> ≈ 300 W m− 1 K− 1

Primary Cilium-Dependent Signaling Mechanisms

Primary cilia are hair-like organelles and play crucial roles in vertebrate development, organogenesis, health, and many genetic disorders. A primary cilium is a mechano-sensory organelle that responds to mechanical stimuli in the micro-environment. A cilium is also a chemosensor that senses chemical signals surrounding a cell. The overall function of a cilium is therefore to act as a communication hub to transfer extracellular signals into intracellular responses. Although intracellular calcium has been one of the most studied signaling messengers that transmit extracellular signals into the cells, calcium signaling by various ion channels remains a topic of interest in the field. This may be due to a broad spectrum of cilia functions that are dependent on or independent of utilizing calcium as a second messenger. We therefore revisit and discuss the calcium-dependent and calcium-independent ciliary signaling pathways of Hedgehog, Wnt, PDGFR, Notch, TGF-β, mTOR, OFD1 autophagy, and other GPCR-associated signaling. All of these signaling pathways play crucial roles in various cellular processes, such as in organ and embryonic development, cardiac functioning, planar cell polarity, transactivation, differentiation, the cell cycle, apoptosis, tissue homeostasis, and the immune response

Unsupervised grounding of textual descriptions of object features and actions in video

We propose a novel method for learning visual concepts and their correspondence to the words of a natural language. The concepts and correspondences are jointly inferred from video clips depicting simple actions involving multiple objects, together with corresponding natural language commands that would elicit these actions. Individual objects are first detected, together with quantitative measurements of their colour, shape, location and motion. Visual concepts emerge from the co-occurrence of regions within a measurement space and words of the language. The method is evaluated on a set of videos generated automatically using computer graphics from a database of initial and goal configurations of objects. Each video is annotated with multiple commands in natural language obtained from human annotators using crowd sourcing

Investigation for Success Factors In Using Portals as a Knowledge Sharing Mechanism

Defining the concept of portal as a framework for integrating information, people and processes across organizational boundaries through software solution installed on organization infrastructure which may include internet, intranet, and extranet network. Portals play importance role in knowledge sharing and management as a gateway to all unstructured, structured, and collaborative information and knowledge within organization so that the user can easily work on this personalized platform. Firstly, i would like to explain the functions of some important concepts like portals and knowledge sharing. Furthermore, I will also explain the role of portals in knowledge sharing process and how it can improve the knowledge management in the organization. This paper will discuss and focus on the success factors for excellent portal implementation and how to use the portal to achieve knowledge sharing in the organization. In conclusion, I will determine the success factor on using portal as knowledge sharing tool and how it can improve the knowledge management overall in the organization and how the portal becomes strong point in the organization to publish knowledge sharing culture and support decision making. As Example for the portals, I’ll explain some features for MS SharePoint. Keywords: knowledge management, Portals , MS SharePoin

A qualitative approach for online activity recognition

We present a novel qualitative, dynamic length sliding window method which enables a mobile robot to temporally segment activities taking place in live RGB-D video. We demonstrate how activities can be learned from observations by encoding qualitative spatio-temporal relationships between entities in the scene. We also show how a Nearest Neighbour model can recognise activities taking place even if they temporally co-occur. Our system is validated on a challenging dataset of daily living activities