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In this research effort, we developed MEMS micromirrors which are suitable for large angle deflections for optical scanning applications using the PolyMUMPs™ foundry fabrication process. This foundry process uses polysilicon and gold as the structural layers to form the bimorph beam structures which make up our actuation assembly. From both modeling and experimental testing, current micromirror designs fabricated in the PolyMUMPs™ process do not meet the deflection requirements to enable large angle scanning. As a result, we developed several post processing deposition techniques, using the PolyMUMPs™ structural layers as the baseline structure, to enable the necessary upward deflections to permit large angle scanning. In this research, we design, model, post fabricate, and test high out-of-plane MEMS actuators intended for integration with SOI micromirror arrays to enable the broadband, high fill-factor scanning applications. These arrays are designed to scan in multiple directions due to the segmented actuation design. The upward deflection is accomplished through material selection and design control (i.e., structure length, material thickness, material coefficient of thermal expansion (CTE), deposition temperature, and material layer composition) of bimorph structures. Following the post processed fabrication and sacrificial release; the initial deflection profiles are measured and compared against COMSOL™ models.

MEMS micromirrors for large angle beamsteering are needed for numerous broadband steering and imaging applications. However, current scanning micromirrors generally exhibit scanning angles (

This research effort is focused on the development of a micro-electro-mechanical system (MEMS) energy harvesting device using large, out-of-plane bimorph MEMS structures fabricated in the PolyMUMPs™ foundry process. In general, MEMS designers have limited options for commercial device fabrication, each bringing the advantage of quick prototyping, and repeatable results but also unique limitations. The design rules limit the designers to specific materials, structural layers, and fabrication processes to those of the fabrication facility. In previous work we have shown that the PolyMUMPs™ process will provide an adequate foundational structure for the device, meeting the initial out-of-plane deflection and flexibility requirements. However, it will require some post-processing to add the required mass and piezoelectric material layers to the structures. COMSOL™ finite element modeling software is used to evaluate various mass sizes, orientations, and materials as well as to explore different piezoelectric materials and configurations to produce optimal results from the in-house post-processing of these designs. Initial modeling of the structures illustrates unique design flexibility such that the operational frequency can be tailored to meet specific resonances enabling these devices to be adapted for a multitude of applications. Lastly, since the device provides the added benefit and flexibility, they can easily be integrated into an array for increased output voltage making them a prime candidate for micro power generation circuits.

The objective of this study was to determine the effects of frequency of feed delivery on time budgets of individuallystalled dairy cows. The experiment was conducted as a 2 x 2 crossover design using 12 Holstein dairy cows randomly assigned to 1 of 2 treatments (n = 6): ad libitum feeding of a total mixed ration (TMR) delivered either 2x or 3x daily in a tie-stall operation. The experiment consisted of two 21-d experimental periods (13 d of adaptation and 8-d data collection periods). During the data collection periods, time-lapse video photography was used to quantify time budgets. Frequency of feed delivery had no effect (P > 0.05)on DMI, milk yield, or time budgets of the dairy cows. These results suggest that as long as feed is available to the cows ad libitum, frequency of feed delivery does not seem to affect time budget.

Subacute ruminal acidosis (SARA) was induced by replacing 25% of the total mixed ration intake [dry matter (DM) basis] with pellets consisting of 50% wheat and 50% barley. This reduced dietary forage content (DM basis) from 39.7 to 29.8% and increased the dietary concentrate content from 60.3 to 70.2%. Induction of SARA reduced the 24- and 48-h in situ neutral detergent fiber (NDF) degradabilities of grass hay numerically from 31.5% to 24.6% (P = 0.29) and from 51.3% to 36.9% (P < 0.05), respectively. The 24- and 48-h in situ NDF degradabilities of legume hay were reduced from 35.3 to 26.3% (P < 0.05) and from 49.0 to 35.8% (P < 0.05), respectively. The 24- and 48-h in situ NDF degradabilities of corn silage were reduced from 44.0 to 37.2% (P < 0.05) and from 56.1 to 44.8% (P < 0.05), respectively. This study suggests that induction of SARA by excess feeding of wheat/barley pellets reduces the rumen digestion of NDF from grass hay, legume hay, and corn silage.

The objectives of this study were to examine the effect of supplying post-ruminal L-glutamine in mid-lactation Holstein dairy cows on plasma amino acid profile, dry matter intake, milk yield and milk composition. The experiment was designed as a 4 × 4 Latin square with four 2-wk periods. Cows were continuously infused post-ruminally with graded levels of L-glutamine (L-Gln) for 5 consecutive days during the second week of each period. During the last 24 h of the infusion, blood plasma was collected every 6 h for the determination of plasma amino acid concentrations. Plasma Gln concentration increased (P < 0.05) with increasing L-Gln daily infusions. Infusion of 0, 100, 200, and 300 g d–1 resulted in blood plasma Gln concentrations of 289.5, 299.2, 356.4 and 386.2 mmol L–1, respectively. The level of Gln infusion also resulted in a decrease in the blood plasma concentration of phenylalanine, but the concentrations of all other amino acids were not affected. The administration of Gln did not affect dry matter intake, milk yield and milk composition. Key words: Post-ruminal, L-glutamine, plasma amino acids, milk constituents

Mammals that hibernate must rely on endogenous lipid reserves to survive over winter. This study was conducted to compare the difference in serum fatty acid composition, dietary intake, and apparent digestibility in the Vancouver Island marmot (N = 6) fed the Metro Zoo lagomorph diet supplemented with α-linolenic acid [C(18:3) n-3 (α-LA)]. The experiment was designed as a 3 × 3 Latin square with three 17-day collection periods. The test diets contained 12.16, 14.85, and 17.05% α-LA as a percentage of fatty acids in the diet supplied through the addition of flaxseed oil (∼53% α-LA). Across treatments, dry matter intake (g/d), dry matter digestibility, apparent fat digestibility, and apparent neutral detergent fiber digestibility did not differ significantly (P > 0.05). There were no significant differences in serum α-LA concentration between the three levels of α-LA supplementation. However, this supplementation did elevate serum α-LA, eicosapentaenoic acid [C20:5 (n-3)], and docosahexaenoic acid [C22:6 (n-3)] levels compared with feeding the basal zoo lagomorph diet (P < 0.05). Thus, supplementation of the basal zoo lagomorph diet with α-LA elevated the serum levels of essential fatty acids in the Vancouver Island marmot. Zoo Biol 20:251–259, 2001. © 2001 Wiley-Liss, Inc.

ntroduction. Low-dimensional topology is dominated by the fundamental group. However, since every finitely presented group is the fundamental group of some closed 4-manifold, it is often stated that the effective influence of π1 ends in dimension three. This is not quite true, however, and there are some interesting border disputes. In this paper, we show that, by imposing the extra condition of parallelizability on the tangent bundle, the dominion of π1 is extended by an extra dimension.

We have measured hyperfine-structure splittings and isotope shifts in the $4s{}^{4}{P}_{J}\ensuremath{\rightarrow}4p{}^{4}{D}_{{J}^{\ensuremath{'}}}$ multiplet in atomic chlorine using Doppler-free saturated absorption spectroscopy with an external cavity diode laser. Spectra of seven of the eight components of this multiplet, which have wavelengths between 798 and 859 nm, were obtained. Values for the magnetic dipole and electric quadrupole hyperfine-structure constants of the ${}^{4}{P}_{1/2\ensuremath{-}5/2}$ and ${}^{4}{D}_{1/2\ensuremath{-}7/2}$ states in both ${}^{35}\mathrm{Cl}$ and ${}^{37}\mathrm{Cl}$ were found, and the isotope shifts of the seven transitions studied were measured. The data were also analyzed in an attempt to extract values for magnetic octupole coupling constants for some of the levels investigated, but these were found to be zero at the level of the experimental uncertainty of our measurements.

The MINERvA(6) experiment is designed to perform precision studies of neutrino-nucleus scattering using nu(mu) and (nu) over bar (mu) neutrinos incident at 1-20 GeV in the NuMI beam at Fermilab. This article presents a detailed description of the MINERvA detector and describes the ex situ and in situ techniques employed to characterize the detector and monitor its performance. The detector is composed of a finely segmented scintillator-based inner tracking region surrounded by electromagnetic and hadronic sampling calorimetry. The upstream portion of the detector includes planes of graphite, iron and lead interleaved between tracking planes to facilitate the study of nuclear effects in neutrino interactions. Observations concerning the detector response over sustained periods of running are reported. The detector design and methods of operation have relevance to future neutrino experiments in which segmented scintillator tracking is utilized. (C) 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/3.0/).

Feeding forages containing condensed tannins (CT) can reduce intestinal absorption of amino acids (AA) and peptides. This experiment tested the hypothesis that CT in Lotus pedunculatus altered small intestinal mucosal morphology reducing absorptive capacity of the gut. Thirteen young Romney wethers were fed ad libitum either Lotus pedunculatus (cv. Grasslands Maku, N = 7) containing 5.5% CT in the dry matter (DM) or white clover-perennial ryegrass pasture (N = 6), which did not contain CT, for 4 wk. The wethers were euthanized at the end of the feeding trial and samples were collected for histological examination from the proximal and distal duodenum, proximal, mid-, and distal jejunum and ileum, and ventral rumen. There was no effect of feeding L. pedunculatus containing 5.5% CT (P > 0.05) on rumen or gut morphological parameters in sheep. The cause of reduced AA absorption in the presence of CT is not known, but this study suggests it is not due to changes in intestinal morphology. Key words: Lotus pedunculatus, condensed tannins, gut morphology, sheep

Induction of subacute ruminal acidosis (SARA) by replacing 25% of the total mixed ration (TMR) intake [dry matter (DM) basis] with pellets consisting of 50% wheat and 50% barley, reduced the in situ DM and neutral detergent fibre (NDF) digestion of mixed hay. In situ 48 h NDF disappearance was reduced from 39.5 to 30.9% (P < 0.05). Key words: Sub-acute ruminal acidosis, fibre digestibilty, dairy cows

1. Three experiments were conducted using a low temperature model to induce pulmonary hypertension (PH) and ascites in broiler chickens. Diets containing 25 g or 50 g flax oil/kg food and control diets with an equivalent amount of animal/vegetable (A/V) blend oil, with and without supplemental antioxidants (vitamin C and vitamin E) were used. The amount of PH was assessed by the ratio of right ventricle weight to total ventricle weight (RV/TV ratio). Birds were considered to suffer from pulmonary hypertension syndrome (PHS) if the RV/TV ratio was greater than 0.299. 2. In experiment 1, the test diets contained 50 g oil/kg food and were given during the grower period only. Birds fed on the flax oil diet tended to have a lower incidence of PHS, ascites and lower RV/TV ratios than birds fed on the control diet. However, when the flax oil diet was supplemented with antioxidants, the incidence of ascites, PHS, haematocrit and whole blood and plasma viscosity increased compared with birds fed on the flax oil diet without antioxidants. These effects were not seen in experiment 2, when the test diets containing 30 g oil/kg food (25 g flax oil plus 5 g A/V blend oil/kg food compared to 30 g A/V blend oil/kg food) were given during the grower period. However, in experiment 3, when the test diets containing 30 g oil/kg food were given from day 1 to week 8, birds fed on the control diet supplemented with antioxidants had a higher incidence of PHS than those fed on the control diet alone. 3. In all 3 experiments, there was no significant effect of dietary fat source or supplemental antioxidants on total food intake or food conversion. 4. We conclude that diets containing 50 g flax oil/kg food tend to reduce the incidence of PHS and ascites in broilers using a low temperature model but the results were not statistically significant. In some cases, supplementing diets with a combination of vitamin E and vitamin C increased the incidence of ascites and PHS.

Urinary 3 methyl-histidine excretion was measured in high yielding dairy cows between 10 and 3 d precalving and between 3 and 9 d postcalving. Cows received a sodium monensin controlled-release capsule or a placebo 3 wk before calving. Monensin did not affect urinary 3 methyl-histidine. Average urinary 3 methyl-histidine excretion was significantly higher postcalving (4.11mmol d –1 ) than precalving (2.48 mmol d –1 ). This increase is assumed to be predominantly due to the negative nitrogen balance in the postcalving period caused by insufficient nutrient intake to meet nutrient requirements, which necessitates catabolism of mainly myofibrillar protein.

Whole-nerve action potentials evoked by a standard click were recorded from a gross electrode on the RW and the discharges of auditory nerve fibers to the same standard click were recorded from micropipette electrodes in the auditory nerve. The effect of a preceding tone burst (2, 4, or 8 kHz) upon the responses was measured for forward-masker intensities from 20 to 80 dB SPL. All forward maskers reduced the discharges of auditory nerve fibers to the standard click with the greatest reduction occurring for fibers with characteristic frequencies (CFs) near the masker frequency. The 4- and 8-kHz forward maskers produced similar effects on N1, P1, and N2 of the RW response. However, the 2-kHz forward masker produced enhancement at P1 and N2 in the RW response to the standard click. An empirical summation model of estimated elemental waveforms at latencies dependent on CF produces synthesized AP response waveforms which are similar to the observed RW response. The model permits the exclusion of discharges from segments along the cochlear partition in a manner similar to the effect of a forward masker. Alterations in the synthesized waveforms due to the exclusion of segments are similar in direction to the alterations observed in the RW responses for forward masking.

The discharges of auditory nerve fibers in kittens 4-37 days of age were recorded from micropipette electrodes. Tuning curves, thresholds, and the degree of tuning (Q 10) are compared over this age range. The tuning curves for fibers during the first postnatal week are relatively flat, with thresholds above 100 dB SPL. The response areas of VIII-nerve fibers during this period are restricted to low-to-middle frequencies. With increasing age there is a reduction in threshold and an increase in the sharpness of tuning which is dependent on fiber CF. Response characteristics similar to adult VIII-nerve fibers were observed first for fibers with CFs near 5 kHz. For the response measures used here, VIII-nerve fibers in kittens are adultlike by the third to fourth postnatal week. The results are discussed in relation to the morphological development of the cochlea reported by other investigators.

Acoustic reflex thresholds, latencies and magnitudes were recorded binaurally in decerebrate chinchillas suffering monaural, temporary noise trauma. Simultaneous recordings of cochlear microphonics from both cochleae during monaural reflex stimulation served as an index for acoustic reflex dynamics. Baseline values of threshold, latency and magnitude were recorded from ipsilateral and contralateral ears prior to a monaural 2-hour exposure to a 0.5-kHz octave-band noise at 100 dB SPL. Reflex dynamics were measured immediately after exposure and again following 1 h of recovery. Cochlear microphonic input-output functions for the exposed ear were completed prior to and after cessation of the noise and after 1 h of recovery. Acoustic reflex threshold and magnitude increased and latency decreased following exposure to noise for both the ipsilateral and contralateral recording conditions. Reflex activity in the nonexposed ear was unaffected. Reflex properties returned to pre-exposure values following recovery. These responses followed the same time course as changes in cochlear sensitivity. Alterations in reflex response following noise exposure is caused by changes at purely peripheral sites.

Infants with the diagnosis of persistent fetal circulation were evaluated for hearing loss. From Jan 1, 1982, to Jan 1, 1984, 28 infants with this diagnosis were retrospectively identified, and 18 were evaluated by formal audiologic testing. Additionally, 22 infants were prospectively followed by serial auditory evaluation from Jan 1, 1984, to Jan 1, 1986. Of the 40 infants evaluated, 21 were identified as having hearing impairment (52.5%), 14 of whom required hearing aids. For 82% of those retrospectively identified hearing-impaired infants who required hearing aids, parental concern was expressed for their lack of hearing acuity. This factor could have aided in the earlier recognition of these infants' impairment. Among those infants followed prospectively, formal audiologic testing, in some cases serially, was needed to diagnose a progressive hearing loss that was expressed at 6 to 8 months after discharge from the neonatal intensive care unit. Perinatal factors associated with the development and management of persistent fetal circulation were identified and compared in infants with confirmed hearing loss and those with normal hearing. Variables related to those infants with hearing loss were as follows: degree of alkalosis, duration of ventilation, and possibly use of furosemide. We concluded from these results that infants with persistent fetal circulation have an extremely high incidence of sensorineural hearing loss and suggest serial formal audiologic evaluations to aid in detection of hearing-impaired infants.

Discharges of auditory nerve fibers to broadband clicks were masked with tone bursts (rise time, 1 ms; duration, 30 ms) of 4,8, or 13 kHz. The tone burst preceded the click by 10 ms, thus the click response was subjected to “forward masking.” Click intensity was set 30 dB above the intensity which produced a just detectable N1 averaged response (256 epochs). After determining CF for each fiber, a PST histogram of the unit's response to the click at the standard intensity was taken. Tone burst frequency was then set at 4, 8, or 13 kHz and PST histograms to the click were recorded as the intensity of the tone bursts was increased in 10 dB steps. The reduction in click responses by each forward masker was measured for units distributed over a range of CF for constant masker intensities. The discharges of units with CFs near the masker frequency are reduced by the greatest amount, those from units with CFs below masker frequency may show an increase in discharges to the click. [Supported by NSF, No. BNS‐77‐16...

The acoustic pressures produced by a band of noise were measured at the entrance to the auditory canal and near the tympanum. The stimuli was produced by a TDH‐39 earphone activated by a noise band tailored to produce an approximately flat spectrum between 0.1 and about 4 kHz at the entrance to the ear canal. A computer program calculated the output power spectra, the signal/noise, the cross‐power spectrum, the transfer function, the coherence function, and the phase between the input and output power spectra. The transfer function in each animal shows an upper frequency peak, the location of which varies with the apparent volume of the canal, being highest for the guinea pig and lowest for man. The magnitude of the resonance is largest for the cat and smallest for the guinea pig. [Supported in part by DAMD 17‐78C‐8067 and NSF‐77‐16907.]

High‐intensity, low‐frequency octave band noise in the free field has been reported to produce permanent threshold shift at 2 kHz in chinchillas [Burdick, Patterson, Mozo, and Camp, J. Acoust. Soc. Am. 64, 458 (1978)]. We have delivered 100‐ and 250‐Hz low‐pass noise to the chinchilla with intact pinna but open bulla and have measured the spectrum of the CM recorded with electrodes in turn I and turn II. SPL's were measured at the pinna. The output of the microphone was led to channel 1 of an A/D converter. The CM was led to channel 2. The inputs to the A/D's were adjusted to the same rms level to minimize digital noise. A computer program calculated FFT's and produced several calculations from them (see previous abstract). At SPL's below 100 dB, the output spectrum (CM) is similar to the input spectrum (microphone). Above 100 dB the output spectrum contains frequencies above the passband of the input spectrum. The coherence function indicates that the high‐frequency output is not present in the input power spectrum. [Supported in part by DAMD17‐78C‐8067 and NSF 77‐16907.]