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Six primiparous Holstein cows were assigned to a half udder design (n=6) 40 days prior to parturition. Beginning at parturition, one udder half was milked once daily (24hr interval) and the other four times daily (6hr interval). Udder halves were biopsied at days 15, 60, 120, and 230 of lactation for mammary tissue to perform mitochondrial staining and apoptosis studies. Increasing the milking frequency from 1x to 4x elevated the 4x udder half milk yield at early (d1-45) (P<0.0001), mid (d46-150) (P<0.0001) and late (d151-230) (P<0.0001) lactation. Milk protein percent (P= 0.013), lactose percent (P=0.004) and SNF percent (P=0.006), were elevated in milk from 4x udder halves over milk from 1x udder halves. We did not detect an effect of increased milking frequency on milk fat percent (P=0.25); however, yield of all components was increased. Increased milking frequency also increased mitochondrial numbers in mammary cells from 4x udder half (P=0.002) compared to 1x. We did not detect an effect of increased milking frequency on mammary apoptosis percentage. We also did not detect a difference in the abundance of gene transcripts for SOCS1, SOCS2, SOCS3 and CIS in milk; but could find an increase in alpha-lactalbumin (P=0.04) and beta-casein (P=0.001) 4x udder half gene transcripts.

This thesis is focused on the high-frequency performance of carbon nanotube field-effect transistors (CNFETs). Such transistors show their promising performance in the nanoscale regime where quantum mechanics dominates. The short-circuit, common-source, unity-current-gain frequency ft is analyzed through regional signal-delay theory. An energy-dependent effective-mass feature has been added to an existing SP solver and used to compare with results from a constant-effective-mass SP solver. At high drain bias, where electron energies considerably higher than the edge of the first conduction sub-band may be encountered, ft for CNFETs is significantly reduced with respect to predictions using a constant effective mass. The opinion that the band-structure-determined velocity limits the high-frequency performance has been reinforced by performing simulations for p-i-n and n-i-n CNFETs. This necessitated incorporating band-to-band tunneling into the SP solver. Finally, to help put the results from different CNFETs into perspective, a meaningful comparison between CNFETs with doped-contacts and metallic contacts has been made. Band-to-band tunneling, which is a characteristic feature of p-i-n CNFETs, can also occur in n-i-n CNFETs, and it reduces the ft dramatically.

Radio Frequency Identification (RFID) is an emerging area under ubiquitous computing. RFID benefits include multiple read/write, longer read range and no requirement for line of sight. Due to security and privacy issues, RFID is not as popular as it should be. Tag cloning is one of the biggest threats to RFID systems. Easy access to RFID tags allows an attacker to replicate the tags and insert duplicate tags into the system. An RFID tag cloning attack can lead to access control or financial frauds in areas like supply chain management and government issued IDs. In this thesis, a cloning prevention protocol is proposed. It uses light weight functions such as Pseudo Random Number Generator (PRNG) and compare function. A 3-way handshake with a secret key, frequency hopping mechanism and dynamic fake ID makes this protocol a secure authentication mechanism.

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This thesis is concerned with various aspects of stationary and nonstationary time series analysis. In the nonstationary case, we study estimation of the Wold-Cram'er evolutionary spectrum, which is a time-dependent analogue of the spectrum of a stationary process. Existing estimators of the Wold-Cram'er evolutionary spectrum suffer from several problems, including bias in boundary regions of the time-frequency plane, poor frequency resolution, and an inability to handle the presence of purely harmonic frequencies. We propose techniques to handle all three of these problems. We propose a new estimator of the Wold-Cram'er evolutionary spectrum (the BCMTFSE) which mitigates the first problem. Our estimator is based on an extrapolation of the Wold-Cram'er evolutionary spectrum in time, using an estimate of its time derivative. We apply our estimator to a set of simulated nonstationary processes with known Wold-Cram'er evolutionary spectra to demonstrate its performance. We also propose an estimator of the Wold-Cram'er evolutionary spectrum, valid for uniformly modulated processes (UMPs). This estimator mitigates the second problem, by exploiting the structure of UMPs to improve the frequency resolution of the BCMTFSE. We apply this estimator to a simulated UMP with known Wold-Cram'er evolutionary spectrum. To deal with the third problem, one can detect and remove purely harmonic frequencies before applying the BCMTFSE. Doing so requires a consideration of the aliasing problem. We propose a frequency-domain technique to detect and unalias aliased frequencies in bivariate time series, based on the observation that aliasing manifests as nonlinearity in the phase of the complex coherency between a stationary process and a time-delayed version of itself. To illustrate this ``unaliasing'' technique, we apply it to simulated data and a real-world example of solar noon flux data. / Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2009-02-05 10:18:13.476

The pathophysiology of essential tremor (ET) is not clearly understood but is thought to involve multiple brain regions. The purpose of this study was to describe in greater detail head tremor in ET and to investigate the possible relationship between head and hand tremor. Ten ET subjects were recruited (1 male, 9 female) and compared to three control subjects (1 male, 2 female). Head and hand tremors were recorded simultaneously with surface electromyography (EMG) of the wrist extensors and various neck muscles, laser displacement sensors (hand tremor), a load cell (hand tremor) and an accelerometer (head tremor). While seated, subjects performed four tasks: 1) constant force (10% maximum) wrist extensions (with and without visual feedback); maintenance of the hands in a horizontal posture against gravity while 2) seated upright in a chair, 3) seated in a reclined chair (20° backward, head not supported); and 4) seated upright in a chair and producing steady submaximal hip adduction forces. Head tremor spectral peaks were found between 3.5 and 7 Hz in neck muscle EMG and the accelerometer signal. Wrist tremor (EMG and kinematic data) was slightly higher in frequency with a range of 4 -10 Hz. Of the ten ET subjects recruited for this study, 60% (n = 6) demonstrated significant levels of coherence (p < 0.05) in at least one neck-wrist muscle comparison at the fundamental frequency of their tremor. The results demonstrated an obvious bias of the trapezius descendens (TD) muscles over the more axial neck muscles to demonstrate significant coherence with the extensor carpi radialis (ECR) muscles. Of the six neck muscles investigated, the SPLs and the SCMs were commonly driven at the same frequencies (change in frequency < 0.5), although this seldom resulted in coherence. There is indication that the oscillatory activity driving more distal muscles is different from that in the SPL and the SCM. Due to the multifunctional nature of the TD, it may be the recipient of two descending neural commands. These commands may each be of a different oscillatory frequency originating from different central oscillators. / Thesis (Master, Neuroscience Studies) -- Queen's University, 2008-10-29 10:03:22.354

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