Ovulation rate and its relationship with follicle diameter and gene expression of the LH receptor (LHR) in Nelore cows

The objective was to determine the relationship among the diameter of ovarian follicles, ovulation rate, and gene expression of the LH receptor (LHR) in Nelore cattle. In Experiment 1, ovulation was synchronized in 53 Nelore cows. Three days after ovulation, ovaries were assessed with ultrasonography, all cows were given 6.25 mg LH im, and they were allocated into three groups, according to diameter of their largest ovarian follicle: G1 (7.0-8.0 mm); G2 (8.1-9.0 mm); and G3 (9.1-10.0 mm). For these three groups, ovulation rates were 9, 36, and 90%, respectively, (P < 0.03; each rate differed significantly from the other two). In Experiment 2, granulosa and theca cells were subjected to total RNA extraction, and gene expression of the LHR was determined by RT-PCR. Follicles were allocated in three groups based on their diameter (similar to the Experiment 1), which were denoted Groups A, B, and C. Expression of the LHR gene in granulosa cells was lower in Group A than Group C (P < 0.05). However, there were no significant differences among groups in expression of the LHR gene in theca cells. We concluded that ovulatory capacity in Nelore cattle was related to increased follicular diameter and expression of the LHR gene in granulosa cells. (C) 2012 Elsevier B.V. All rights reserved.

Ovarian follicle diameter at timed insemination and estrous response influence likelihood of ovulation and pregnancy after estrous synchronization with progesterone or progestin-based protocols in suckled Bos indicus cows

The objectives of the present study were to evaluate factors associated with estrous synchronization responses and pregnancy per insemination (P/AI) in Bos indicus beef cows submitted to progesterone-based fixed-time artificial insemination (FTAI) protocols. A total of 2388 cows (1869 Nellore and 519 crossbred Nellore x Angus) from 10 commercial farms were evaluated to determine the relationships among breed, body condition score (BCS) on the first day of the FTAI protocol, the occurrence of estrus between progesterone device removal and FTAI and diameter of largest ovarian follicle (LF) at FTAI on estrous synchronization responses and P/AI. Cows (n=412 primiparous; 1976 multiparous) received an intravaginal device containing progesterone or an ear implant containing norgestomet (a progestin), and an injection of estradiol at the beginning of the estrous synchronization protocol. Body condition was scored using a 1-5 scale on the first day of the FTAI protocol and at 30-60 days postpartum. Females received 300IU of equine chorionic gonadotropin (eCG) and PGF(2 alpha) on the day the progesterone device/implant was removed and were inseminated 48-60h later. At insemination, cows (n=2388) were submitted to an ultrasonographic exam to determine the diameter of the LF. Follicles were classified into four categories based on mean and standard deviation (SD) of the LF (LF1 = two SD below the mean; LF2 = mean minus one SD; LF3 = mean plus one SD; LF4 = two SD above the mean). Ovulation rate was determined in a subset of cows (n=813) by three consecutive ultrasonographic exams: (1) at time of progesterone device/implant removal, (2) at time of FTAI and (3) 48 h after FTAI. Ovulation was defined as the disappearance of a large follicle (>= 8.0 mm) that was previously recorded. Estrus was determined in a subset of the cows (n = 445) by the activation of a detection of estrous patch placed on the tail head on the day of progesterone device/implant removal. Pregnancy was diagnosed 30 days after FTAI. Pregnancy was influenced (P = 0.001) by follicle diameter [LF1 = 27.5% (81/295), LF2 = 46.6% (328/705), LF3 = 57.9% (647/1118), LF4 = 63.3% (171/270)] and the occurrence of estrus [estrus = 67.7% (174/257) and no estrus = 36.2% (68/188)]. Follicle diameter at FTAI influenced ovulation rate [LF1 = 42.5% (34/80), LF2 = 73.9% (161/218), LF3 = 95.8% (407/425), LF4 = 97.8% (88/90)], the occurrence of estrus [LF1 = 54.8% (51/93), LF2 = 33.6% (43/128), LF3 = 68.9% (126/183), LF4 = 90.2% (37/41)] and P/AI among cows that had ovulations [LF1 =32.4% (11/34), LF2 = 50.3% (81/161), LF3 = 60.0% (244/407), LF4 = 68.2% (60/88)]. Improving estrous responses between progesterone device withdrawal and FTAI and increasing the diameter of the LF at FTAI may be important aspects to achieve improved estrous synchronization responses and P/AI following progesterone/progestin and estradiol based FTAI protocols in suckled Bos indicus cows. (C) 2010 Elsevier B.V. All rights reserved.

Maximum and mean diameter record of Orbulina universa from DSDP Hole 47-397 of Cape Bojador, eastern North Atlantic

Measurements of the diameter of O. universa carried out on 30 specimens from 39 samples covering a sediment thickness of 78 m and going back in time to approximately 750 000 y resulted in the construction of a curve of the mean diameter and a curve of the maximum diameter. Both curves, as well as those calculated with the running-averages technique, display cyclic fluctuations with durations of the order of 100 000 y and downwards decreasing amplitudes. These curves are compared with a carbonate curve (on bulk sediment) and an isotopic curve (on benthic foraminifers) obtained from the same set of samples. Correlations are fair to good, but a timelag is noticed between the isotopic curve and the faunal (O. universa mean diameter) curve, with the isotopic signal coming first, in the middle part of the Brunhes Epoch. Biostratigraphic calibration to the paleomagnetic record is provided by four datum planes (two based on calcareous nannofossils, two on diatoms) identified in the succession. Changes recorded in test porosity seem to be less meaningful than changes in test size.

Woodleigh, Southern Carnarvon Basin, Western Australia: history of discovery, Late Devonian age, and geophysical and morphometric evidence for a 120 km-diameter impact structure

The discovery of the Woodleigh impact structure, first identified by R. P. lasky, bears a number of parallels with that of the Chlcxulub impact structure of K-T boundary age, underpinning complications inherent in the study of buried impact structures by geophysical techniques and drilling. Questions raised in connection with the diameter of the Woodleigh impact structure reflect uncertainties in criteria used to define original crater sizes in eroded and buried impact structures as well as limits on the geological controls at Woodleigh. The truncation of the regional Ajona - Wandagee gravity ridges by the outer aureole of the Woodleigh structure, a superposed arcuate magnetic anomaly along the eastern part of the structure, seismic-reflection data indicating a central > 37 km-diameter dome, correlation of fault patterns between Woodleigh and less-deeply eroded impact structures (Ries crater, Chesapeake Bay), and morphometric estimates all indicate a final diameter of 120 km. At Woodleigh, pre-hydrothermal shock-induced melting and diaplectic transformations are heavily masked by pervasive alteration of the shocked gneisses to montmorillonite-dominated clays, accounting for the high MgO and low K2O of cryptocrystalline components. The possible contamination of sub-crater levels of the Woodlelgh impact structure by meteoritic components, suggested by high Ni, Co, Cr, Ni/ Co and Ni/Cr ratios, requires further siderophile element analyses of vein materials. Although stratigraphic age constraints on the impact event are broad (post-Middle Devonian to pre-Early Jurassic) high-temperature (200-250 degrees C) pervasive hydrothermal activity dated by K-Ar isotopes of illite - smectite indicates an age of 359 +/- 4 Ma. To date neither Late Devonian crater fill, nor impact ejecta fallout units have been identified, although metallic meteoritic ablation spherules of a similar age have been found in the Conning Basin.

A model for continuous measurement of drilled shaft diameter during construction

Non-Destructive Testing (NDT) of deep foundations has become an integral part of the industry's standard manufacturing processes. It is not unusual for the evaluation of the integrity of the concrete to include the measurement of ultrasonic wave speeds. Numerous methods have been proposed that use the propagation speed of ultrasonic waves to check the integrity of concrete for drilled shaft foundations. All such methods evaluate the integrity of the concrete inside the cage and between the access tubes. The integrity of the concrete outside the cage remains to be considered to determine the location of the border between the concrete and the soil in order to obtain the diameter of the drilled shaft. It is also economic to devise a methodology to obtain the diameter of the drilled shaft using the Cross-Hole Sonic Logging system (CSL). Performing such a methodology using the CSL and following the CSL tests is performed and used to check the integrity of the inside concrete, thus allowing the determination of the drilled shaft diameter without having to set up another NDT device.^ This proposed new method is based on the installation of galvanized tubes outside the shaft across from each inside tube, and performing the CSL test between the inside and outside tubes. From the performed experimental work a model is developed to evaluate the relationship between the thickness of concrete and the ultrasonic wave properties using signal processing. The experimental results show that there is a direct correlation between concrete thicknesses outside the cage and maximum amplitude of the received signal obtained from frequency domain data. This study demonstrates how this new method to measuring the diameter of drilled shafts during construction using a NDT method overcomes the limitations of currently-used methods. ^ In the other part of study, a new method is proposed to visualize and quantify the extent and location of the defects. It is based on a color change in the frequency amplitude of the signal recorded by the receiver probe in the location of defects and it is called Frequency Tomography Analysis (FTA). Time-domain data is transferred to frequency-domain data of the signals propagated between tubes using Fast Fourier Transform (FFT). Then, distribution of the FTA will be evaluated. This method is employed after CSL has determined the high probability of an anomaly in a given area and is applied to improve location accuracy and to further characterize the feature. The technique has a very good resolution and clarifies the exact depth location of any void or defect through the length of the drilled shaft for the voids inside the cage. ^ The last part of study also evaluates the effect of voids inside and outside the reinforcement cage and corrosion in the longitudinal bars on the strength and axial load capacity of drilled shafts. The objective is to quantify the extent of loss in axial strength and stiffness of drilled shafts due to presence of different types of symmetric voids and corrosion throughout their lengths.^

Diameter-driven crossover in resistive behaviour of heavily doped self-seeded germanium nanowires

The dependence of the resistivity with changing diameter of heavily-doped self-seeded germanium nanowires was studied for the diameter range 40 to 11 nm. The experimental data reveal an initial strong reduction of the resistivity with diameter decrease. At about 20 nm a region of slowly varying resistivity emerges with a peak feature around 14 nm. For diameters above 20 nm, nanowires were found to be describable by classical means. For smaller diameters a quantum-based approach was required where we employed the 1D Kubo–Greenwood framework and also revealed the dominant charge carriers to be heavy holes. For both regimes the theoretical results and experimental data agree qualitatively well assuming a spatial spreading of the free holes towards the nanowire centre upon diameter reduction.

A Model for Continuous Measurement of Drilled Shaft Diameter During Construction

Non-Destructive Testing (NDT) of deep foundations has become an integral part of the industry’s standard manufacturing processes. It is not unusual for the evaluation of the integrity of the concrete to include the measurement of ultrasonic wave speeds. Numerous methods have been proposed that use the propagation speed of ultrasonic waves to check the integrity of concrete for drilled shaft foundations. All such methods evaluate the integrity of the concrete inside the cage and between the access tubes. The integrity of the concrete outside the cage remains to be considered to determine the location of the border between the concrete and the soil in order to obtain the diameter of the drilled shaft. It is also economic to devise a methodology to obtain the diameter of the drilled shaft using the Cross-Hole Sonic Logging system (CSL). Performing such a methodology using the CSL and following the CSL tests is performed and used to check the integrity of the inside concrete, thus allowing the determination of the drilled shaft diameter without having to set up another NDT device. This proposed new method is based on the installation of galvanized tubes outside the shaft across from each inside tube, and performing the CSL test between the inside and outside tubes. From the performed experimental work a model is developed to evaluate the relationship between the thickness of concrete and the ultrasonic wave properties using signal processing. The experimental results show that there is a direct correlation between concrete thicknesses outside the cage and maximum amplitude of the received signal obtained from frequency domain data. This study demonstrates how this new method to measuring the diameter of drilled shafts during construction using a NDT method overcomes the limitations of currently-used methods. In the other part of study, a new method is proposed to visualize and quantify the extent and location of the defects. It is based on a color change in the frequency amplitude of the signal recorded by the receiver probe in the location of defects and it is called Frequency Tomography Analysis (FTA). Time-domain data is transferred to frequency-domain data of the signals propagated between tubes using Fast Fourier Transform (FFT). Then, distribution of the FTA will be evaluated. This method is employed after CSL has determined the high probability of an anomaly in a given area and is applied to improve location accuracy and to further characterize the feature. The technique has a very good resolution and clarifies the exact depth location of any void or defect through the length of the drilled shaft for the voids inside the cage. The last part of study also evaluates the effect of voids inside and outside the reinforcement cage and corrosion in the longitudinal bars on the strength and axial load capacity of drilled shafts. The objective is to quantify the extent of loss in axial strength and stiffness of drilled shafts due to presence of different types of symmetric voids and corrosion throughout their lengths.

Growth and survival of Sclerolobium paniculatum vogel and the relationship between rainfall and the increment in diameter at different planting spacings.

Sclerolobium paniculatum Vogel is a species that has good potential for reclamation of degraded soils. The aim of the investigation was to evaluate the growth and survival of the species and the influence of rainfall on growth in diameter as a function of different spacings (4 m x 2 m, 4 m x 3 m, and 4 m x 4 m). The results indicate that the temporal analysis (period from November 2007 to August 2013) detected significant differences (p ? 0.05) in height between the 4 m x 2 m and 4 m x 4 m spacings, while no significant difference in diameter was found between the 4 m x 2 m and 4 m x 3 m spacings. However, the statistical differences did not persist when the data was analyzed at seven and half years old. Regarding survival, a significant difference was observed only between the 4 m x 4 m spacing and the others, with superiority to the former. A strong correlation was found between rainfall and the increment in diameter of individuals in the broader spacings (R = 0.80 in the 4 m x 3 m spacing and R = 0.77 in the 4 m x 4 m spacing), while in the denser spacing the correlation was moderate (R = 0.56 in the 4 m x 2 m spacing). Since the spacings adopted did not influence tree growth by the end of the period, the choice will depend on other factors such as survival and costs of implementation and forestry management. Plantations in regions with larger rainfall amplitude may benefit the productivity of the species.

Characterization of expiration air jets and droplet size distributions immediately at the mouth opening

Size distributions of expiratory droplets expelled during coughing and speaking and the velocities of the expiration air jets of healthy volunteers were measured. Droplet size was measured using the Interferometric Mie imaging (IMI) technique while the Particle Image Velocimetry (PIV) technique was used for measuring air velocity. These techniques allowed measurements in close proximity to the mouth and avoided air sampling losses. The average expiration air velocity was 11.7 m/s for coughing and 3.9 m/s for speaking. Under the experimental setting, evaporation and condensation effects had negligible impact on the measured droplet size. The geometric mean diameter of droplets from coughing was 13.5m and it was 16.0m for speaking (counting 1 to 100). The estimated total number of droplets expelled ranged from 947 – 2085 per cough and 112 – 6720 for speaking. The estimated droplet concentrations for coughing ranged from 2.4 - 5.2cm-3 per cough and 0.004 – 0.223 cm-3 for speaking.

Biomechanical force displacement analysis of strength of fixation of tracker holding devices to bone in computer aided joint replacement

Computer aided joint replacement surgery has become very popular during recent years and is being done in increasing numbers all over the world. The accuracy of the system depends to a major extent, on accurate registration and immobility of the tracker attachment devices to the bone. This study was designed to asses the forces needed to displace the tracker attachment devices in the bone simulators. Bone simulators were used to maintain the uniformity of the bone structure during the study. The fixation devices tested were 3mm diameter self drilling, self tapping threaded pin, 4mm diameter self tapping cortical threaded pin, 5mm diameter self tapping cancellous threaded pin and a triplanar fixation device ‘ortholock’ used with three 3mm pins. All the devices were tested for pull out, translational and rotational forces in unicortical and bicortical fixation modes. Also tested was the normal bang strength and forces generated by leaning on the devices. The forces required to produce translation increased with the increasing diameter of the pins. These were 105N, 185N, and 225N for the unicortical fixations and 130N, 200N, 225N for the bicortical fixations for 3mm, 4mm and 5mm diameter pins respectively. The forces required to pull out the pins were 1475N, 1650N, 2050N for the unicortical, 1020N, 3044N and 3042N for the bicortical fixated 3mm, 4mm and 5mm diameter pins. The ortholock translational and pull out strength was tested to 900N and 920N respectively and still it did not fail. Rotatory forces required to displace the tracker on pins was to the magnitude of 30N before failure. The ortholock device had rotational forces applied up to 135N and still did not fail. The manual leaning forces and the sudden bang forces generated were of the magnitude of 210N and 150N respectively. The strength of the fixation pins increases with increasing diameter from three to five mm for the translational forces. There is no significant difference in pull out forces of four mm and five mm diameter pins though it is more that the three mm diameter pins. This is because of the failure of material at that stage rather than the fixation device. The rotatory forces required to displace the tracker are very small and much less that that can be produced by the surgeon or assistants in single pins. Although the ortholock device was tested to 135N in rotation without failing, one has to be very careful not to put any forces during the operation on the tracker devices to ensure the accuracy of the procedure.

Selective growth of carbon nanotubes on bare silicon : MWNT sinthesys on patterned substrates without predeposition of metal catalyst

Carbon nanotubes (CNTs) are expected to become the ideal constituent of many technologes, in particular for future generation electronics. This considerable interest is due to their unique electrical and mechanical properties. They show indeed super-high current-carrying capacity, ballistic electron transport and good field-emission properties. Then, these superior features make CNTs the most promising building blocks for electronic devices, as organic solar cells and organic light emitting devices (OLED). By using Focused Ion Beam (FIB) patterning it is possible to a obtain a high control on position, relative distances and diameter of CNTs. The present work shows how to grow three-dimensional architecture made of vertical-aligned CNTs directly on silicon. Thanks to the higher activity of a pre-patterned surface the synthesis process results very quick, cheap and simple. Such large area growths of CNTs could be used in preliminary test for application as electrodes for organic solar cells.

Melt electrospinning of polycaprolactone and its blends with poly(ethylene glycol)

Melt electrospinning is one aspect of electrospinning with relatively little published literature, although the technique avoids solvent accumulation and/or toxicity which is favoured in certain applications. In the study reported, we melt-electrospun blends of poly(ε-caprolactone) (PCL) and an amphiphilic diblock copolymer consisting of poly(ethylene glycol) and PCL segments (PEG-block-PCL). A custom-made electrospinning apparatus was built and various combinations of instrument parameters such as voltage and polymer feeding rate were investigated. Pure PEG-block-PCL copolymer melt electrospinning did not result in consistent and uniform fibres due to the low molecular weight, while blends of PCL and PEG-block-PCL, for some parameter combinations and certain weight ratios of the two components, were able to produce continuous fibres significantly thinner (average diameter of ca 2 µm) compared to pure PCL. The PCL fibres obtained had average diameters ranging from 6 to 33 µm and meshes were uniform for the lowest voltage employed while mesh uniformity decreased when the voltage was increased. This approach shows that PCL and blends of PEG-block-PCL and PCL can be readily processed by melt electrospinning to obtain fibrous meshes with varied average diameters and morphologies that are of interest for tissue engineering purposes. Copyright © 2010 Society of Chemical Industry

Synthesis and characterisation of hybrid gold/polymer nanoparticles for bioassay application

A bioassay technique, based on surface-enhanced Raman scattering (SERS) tagged gold nanoparticles encapsulated with a biotin functionalised polymer, has been demonstrated through the spectroscopic detection of a streptavidin binding event. A methodical series of steps preceded these results: synthesis of nanoparticles which were found to give a reproducible SERS signal; design and synthesis of polymers with RAFT-functional end groups able to encapsulate the gold nanoparticle. The polymer also enabled the attachment of a biotin molecule functionalised so that it could be attached to the hybrid nanoparticle through a modular process. Finally, the demonstrations of a positive bioassay for this model construct using streptavidin/biotin binding. The synthesis of silver and gold nanoparticles was performed by using tri-sodium citrate as the reducing agent. The shape of the silver nanoparticles was quite difficult to control. Gold nanoparticles were able to be prepared in more regular shapes (spherical) and therefore gave a more consistent and reproducible SERS signal. The synthesis of gold nanoparticles with a diameter of 30 nm was the most reproducible and these were also stable over the longest periods of time. From the SERS results the optimal size of gold nanoparticles was found to be approximately 30 nm. Obtaining a consistent SERS signal with nanoparticles smaller than this was particularly difficult. Nanoparticles more than 50 nm in diameter were too large to remain suspended for longer than a day or two and formed a precipitate, rendering the solutions useless for our desired application. Gold nanoparticles dispersed in water were able to be stabilised by the addition of as-synthesised polymers dissolved in a water miscible solvent. Polymer stabilised AuNPs could not be formed from polymers synthesised by conventional free radical polymerization, i.e. polymers that did not possess a sulphur containing end-group. This indicated that the sulphur-containing functionality present within the polymers was essential for the self assembly process to occur. Polymer stabilization of the gold colloid was evidenced by a range of techniques including, visible spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and Raman spectroscopy. After treatment of the hybrid nanoparticles with a series of SERS tags, focussing on 2-quinolinethiol the SERS signals were found to have comparable signal intensity to the citrate stabilised gold nanoparticles. This finding illustrates that the stabilization process does not interfere with the ability of gold nanoparticles to act as substrates for the SERS effect. Incorporation of a biotin moiety into the hybrid nanoparticles was achieved through a =click‘ reaction between an alkyne-functionalised polymer and an azido-functionalised biotin analogue. This functionalized biotin was prepared through a 4-step synthesis from biotin. Upon exposure of the surface-bound streptavidin to biotin-functionalised polymer hybrid gold nanoparticles, then washing, a SERS signal was obtained from the 2-quinolinethiol which was attached to the gold nanoparticles (positive assay). After exposure to functionalised polymer hybrid gold nanoparticles without biotin present then washing a SERS signal was not obtained as the nanoparticles did not bind to the streptavidin (negative assay). These results illustrate the applicability of the use of SERS active functional-polymer encapsulated gold nanoparticles for bioassay application.

Technical note : a technique for measuring the surface area of articular cartilage in acetabular fractures

The aim of this study was to develop a reliable technique for measuring the area of a curved surface from an axial computed tomography (CT) scan and to apply this clinically in the measurement of articular cartilage surface area in acetabular fractures. The method used was a triangulation algorithm. In order to determine the accuracy of the technique, areas of hemispheres of known size were measured to give the percentage error in area measurement. Seven such hemispheres were machined into a Perspex block and their area measured geometrically, and also from CT scans by means of the triangulation algorithm. Scans of 1, 2 and 4 mm slice thickness and separation were used. The error varied with slice thickness and hemisphere diameter. It was shown that the 2 mm slice thickness provides the most accurate area measurement, while 1 mm cuts overestimate and 4 mm cuts underestimate the area. For a hemisphere diameter of 5 cm, which is of similar size to the acetabulum, the error was -11.2% for 4 mm cuts, +4.2% for 2 mm cuts and + 5.1% for 1 mm cuts. As expected, area measurement was more accurate for larger hemispheres. This method can be applied clinically to quantify acetabular fractures by measuring the percentage area of intact articular cartilage. In the case of both column fractures, the percentage area of secondary congruence can be determined. This technique of quantifying acetabular fractures has a potential clinical application as a prognostic factor and an indication for surgery in the long term.

Graph rigidity for near-coplanar structure from motion

Recent algorithms for monocular motion capture (MoCap) estimate weak-perspective camera matrices between images using a small subset of approximately-rigid points on the human body (i.e. the torso and hip). A problem with this approach, however, is that these points are often close to coplanar, causing canonical linear factorisation algorithms for rigid structure from motion (SFM) to become extremely sensitive to noise. In this paper, we propose an alternative solution to weak-perspective SFM based on a convex relaxation of graph rigidity. We demonstrate the success of our algorithm on both synthetic and real world data, allowing for much improved solutions to marker less MoCap problems on human bodies. Finally, we propose an approach to solve the two-fold ambiguity over bone direction using a k-nearest neighbour kernel density estimator.