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1.
Animal ; 17 Suppl 5: 100888, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37451902

RESUMO

In practice, cows are fed by pen, but a diet is formulated to the nutrient requirements of a single cow. If the DM intake (DMI) of a pen were equal for all cows, this approach would have no error, but cows are grouped into pens on pregnancy and other management factors creating a distribution of DMI. The goal of precision feeding is to meet the requirements of individual animals to increase efficiency and reduce environmental impact but is not achieved when a group is fed as if the individuals have uniform requirements and the DMI distribution is not normal. The hypothesis of this work is that the DMI of cow pens are not normally distributed and the total DMI from the best-fit distribution shape for a cow pen will have lower percentage error to the observed DMI than a prediction of a single DMI that is fed at a uniform level and assumes a normal distribution. Our objective was to describe the distribution shape of DMI by week of lactation, and for different pen types. Pens were generated by randomly assorting cows by the week of lactation from a database into different categories of pen for size and lactation period. These pens were fitted to the best distribution type, and its parameters were used to randomly generate distribution plots that predict the total DMI for each pen. A second predictive model estimated the DMI of each pen using an empirical equation of DMI that was multiplied by the number of cows in the pen to represent feeding of a uniform DMI quantity. The percentage error for the distribution shape model was significantly lower than the empirical model with pen errors being less than 1%. The beta distribution type was the most common distribution to best represent the data of pen DMI. Describing the distribution and using it to predict a total pen DMI provides accurate estimates of feed quantity for a group. Reducing error by using the distribution of DMI for feed formulation, instead of the nutrient requirements of an individual animal can provide a precision nutrition approach to group feeding.


Assuntos
Dieta , Lactação , Humanos , Gravidez , Feminino , Bovinos , Animais , Dieta/veterinária , Estado Nutricional , Leite , Ração Animal/análise
2.
J Dairy Sci ; 104(4): 4290-4302, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33752289

RESUMO

The objective of this clinical trial was to evaluate the effectiveness of probiotic, prebiotic, and synbiotic supplementation on average daily weight gain (ADG), duration of diarrhea, age at incidence of diarrhea, fecal shedding of Cryptosporidium oocysts, enteric pathogens, and the odds of pneumonia in preweaning dairy heifer calves on a commercial dairy. Feeding prebiotics and probiotics may improve health and production of calves. Hence, healthy Holstein heifer calves (n = 1,801) from a large California dairy were enrolled at 4 to 12 h of age and remained in this study until weaning at 60 d of age. Calves were block randomized to 1 of 4 treatments: (1) control, (2) yeast culture enriched with mannan-oligosaccharide (prebiotic), (3) Bacillus subtilis (probiotic), and (4) combination of both products (synbiotic), which were fed in milk twice daily from enrollment until weaning. Serum total protein at enrollment and body weight at 7, 42, and 56 d of age were measured. Fecal consistency was assessed daily for the entire preweaning period. A subgroup of 200 calves had fecal samples collected at 7, 14, 21, and 42 d for microbial culture and enumeration of Cryptosporidium oocysts by direct fluorescent antibody staining. Synbiotic-treated calves had 19 g increased ADG compared with control calves for overall ADG, from 7 to 56 d. From 42 to 56 d, prebiotic-treated calves had 85 g greater ADG and synbiotic-treated calves had 78 g greater ADG than control calves. There was no difference in duration of the first diarrhea episode, hazard of diarrhea, or odds of pneumonia per calf with treatment. Probiotic-treated calves had 100 times lower fecal shedding of Cryptosporidium oocysts at 14 d and prebiotic-treated calves had fewer Escherichia coli and pathogenic E. coli at 42 d compared with control calves. Although there were no effects on duration of diarrhea or pneumonia incidence, greater ADG in the late preweaning period may reflect treatment effects on enteric pathogens during the rearing process. The decreased shedding of Cryptosporidium should reduce infectious pressure, environmental contamination, and public health risks from Cryptosporidium. Our findings suggest ADG and potential health benefits for calves fed prebiotics, probiotics, and synbiotics and can help the dairy industry make informed decisions on the use of these products in dairy production.


Assuntos
Criptosporidiose , Cryptosporidium , Ração Animal , Animais , Bacillus subtilis , Peso Corporal , Bovinos , Diarreia/prevenção & controle , Diarreia/veterinária , Dieta , Escherichia coli , Feminino , Mananas , Oligossacarídeos , Desmame , Aumento de Peso
3.
Icarus ; 291: 107-123, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32908319

RESUMO

Data from the Gravity Recovery and Interior Laboratory (GRAIL) mission have revealed that ~98% of the power of the gravity signal of the Moon at high spherical harmonic degrees correlates with the topography. The remaining 2% of the signal, which cannot be explained by topography, contains information about density variations within the crust. These high-degree Bouguer gravity anomalies are likely caused by small-scale (10's of km) shallow density variations. Here we use gravity inversions to model the small-scale three-dimensional variations in the density of the lunar crust. Inversion results from three non-descript areas yield shallow density variations in the range of 100-200 kg/m3. Three end-member scenarios of variations in porosity, intrusions into the crust, and variations in bulk crustal composition were tested as possible sources of the density variations. We find that the density anomalies can be caused entirely by changes in porosity. Characteristics of density anomalies in the South Pole-Aitken basin also support porosity as a primary source of these variations. Mafic intrusions into the crust could explain many, but not all of the anomalies. Additionally, variations in crustal composition revealed by spectral data could only explain a small fraction of the density anomalies. Nevertheless, all three sources of density variations likely contribute. Collectively, results from this study of GRAIL gravity data, combined with other studies of remote sensing data and lunar samples, show that the lunar crust exhibits variations in density by ±10% over scales ranging from centimeters to 100's of kilometers.

4.
IEEE Trans Syst Man Cybern B Cybern ; 42(4): 1006-16, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22581139

RESUMO

For facial expression recognition systems to be applicable in the real world, they need to be able to detect and track a previously unseen person's face and its facial movements accurately in realistic environments. A highly plausible solution involves performing a "dense" form of alignment, where 60-70 fiducial facial points are tracked with high accuracy. The problem is that, in practice, this type of dense alignment had so far been impossible to achieve in a generic sense, mainly due to poor reliability and robustness. Instead, many expression detection methods have opted for a "coarse" form of face alignment, followed by an application of a biologically inspired appearance descriptor such as the histogram of oriented gradients or Gabor magnitudes. Encouragingly, recent advances to a number of dense alignment algorithms have demonstrated both high reliability and accuracy for unseen subjects [e.g., constrained local models (CLMs)]. This begs the question: Aside from countering against illumination variation, what do these appearance descriptors do that standard pixel representations do not? In this paper, we show that, when close to perfect alignment is obtained, there is no real benefit in employing these different appearance-based representations (under consistent illumination conditions). In fact, when misalignment does occur, we show that these appearance descriptors do work well by encoding robustness to alignment error. For this work, we compared two popular methods for dense alignment-subject-dependent active appearance models versus subject-independent CLMs-on the task of action-unit detection. These comparisons were conducted through a battery of experiments across various publicly available data sets (i.e., CK+, Pain, M3, and GEMEP-FERA). We also report our performance in the recent 2011 Facial Expression Recognition and Analysis Challenge for the subject-independent task.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 68(4): 1036-45, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17723318

RESUMO

Combined remote laser-induced breakdown spectroscopy (LIBS) and Raman spectroscopy investigations at a distance of 8.6m have been carried out in air and under a simulated Martian atmosphere of 933Pa (7Torr) CO(2) on calcite (CaCO(3)), gypsum (CaSO(4).2H(2)O), and elemental sulfur (S), and LIBS investigations on chalcopyrite (CuFeS(2)) and pyrite (FeS(2)). Both Raman and LIBS techniques have also been used sequentially in air on hematite-coated calcite crystals and on a sample of anhydrite covered with basaltic dust. These experiments demonstrate that by using a frequency-doubled Nd:YAG pulsed laser co-radiating 1064 nm and 532 nm laser beams with a 5x beam expander, it is possible to measure simultaneously both the Raman and LIBS spectra of calcite, gypsum and elemental sulfur by adjusting the laser power electronically. The spectra of calcite, gypsum, and elemental sulfur contain fingerprint Raman lines; however, it was not possible to measure the remote Raman spectra of pyrite and chalcopyrite because of low intensities of Raman lines. In the cases of CuFeS(2), FeS(2), and elemental sulfur, S atomic emission lines in the LIBS spectra were detected only in 7Torr of CO(2) pressure and not in air. No S atomic emission lines were detected for gypsum in air or in CO(2). In the case of coated/dusted minerals, it was possible to remove the coating or dust with the focused LIBS laser and measure the Raman spectra of subsurface minerals with a 532 nm laser excitation. The complementary nature of these two techniques is highlighted and discussed.


Assuntos
Poeira/análise , Compostos Férricos/química , Lasers , Minerais/química , Silicatos/química , Análise Espectral Raman , Enxofre/química , Carbonato de Cálcio/química
6.
Appl Spectrosc ; 60(8): 871-6, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16925922

RESUMO

A portable pulsed remote Raman spectroscopy system has been fabricated and tested to 100 m radial distance. The remote Raman system is based on a directly coupled f/2.2 spectrograph with a small (125 mm diameter) telescope and a frequency-doubled Nd:YAG pulsed laser (20 Hz, 532 nm, 25 mJ/pulse) used as the excitation source in a co-axial geometry. The performance of the Raman system is demonstrated by measuring the gated Raman spectra of calcite, sodium phosphate, acetone, and naphthalene. Raman spectra of these materials were recorded with the 532 nm pulsed laser excitation and accumulating the spectra with 600 laser shots (30 s integration time) at 100 m with good signal-to-background ratio. The remote pulsed Raman system can be used for remotely identifying both inorganic and organic materials during daytime or nighttime. The system will be useful for terrestrial applications such as monitoring environmental pollution and for detecting minerals and organic materials such as polycyclic aromatic hydrocarbons (PAHs) on planetary surfaces such as Mars.

7.
Nature ; 413(6854): 390-3, 2001 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-11574879

RESUMO

The NEAR-Shoemaker spacecraft was designed to provide a comprehensive characterization of the S-type asteroid 433 Eros (refs 1,2,3), an irregularly shaped body with approximate dimensions of 34 x 13 x 13 km. Following the completion of its year-long investigation, the mission was terminated with a controlled descent to its surface, in order to provide extremely high resolution images. Here we report the results of the descent on 12 February 2001, during which 70 images were obtained. The landing area is marked by a paucity of small craters and an abundance of 'ejecta blocks'. The properties and distribution of ejecta blocks are discussed in a companion paper. The last sequence of images reveals a transition from the blocky surface to a smooth area, which we interpret as a 'pond'. Properties of the 'ponds' are discussed in a second companion paper. The closest image, from an altitude of 129 m, shows the interior of a 100-m-diameter crater at 1-cm resolution.

8.
Science ; 292(5516): 484-8, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11313490

RESUMO

On 25 October 2000, the Near Earth Asteroid Rendevous (NEAR)-Shoemaker spacecraft executed a low-altitude flyover of asteroid 433 Eros, making it possible to image the surface at a resolution of about 1 meter per pixel. The images reveal an evolved surface distinguished by an abundance of ejecta blocks, a dearth of small craters, and smooth material infilling some topographic lows. The subdued appearance of craters of different diameters and the variety of blocks and different degrees of their burial suggest that ejecta from several impact events blanketed the region imaged at closest approach and led to the building up of a substantial and complex regolith consisting of fine materials and abundant meter-sized blocks.

9.
Science ; 289(5487): 2088-97, 2000 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-11000105

RESUMO

Eros is a very elongated (34 kilometers by 11 kilometers by 11 kilometers) asteroid, most of the surface of which is saturated with craters smaller than 1 kilometer in diameter. The largest crater is 5.5 kilometers across, but there is a 10-kilometer saddle-like depression with attributes of a large degraded crater. Surface lineations, both grooves and ridges, are prominent on Eros; some probably exploit planes of weakness produced by collisions on Eros and/or its parent body. Ejecta blocks (30 to 100 meters across) are abundant but not uniformly distributed over the surface. Albedo variations are restricted to the inner walls of certain craters and may be related to downslope movement of regolith. On scales of 200 meters to 1 kilometer, Eros is more bland in terms of color variations than Gaspra or Ida. Spectra (800 to 2500 nanometers) are consistent with an ordinary chondrite composition for which the measured mean density of 2.67 +/- 0.1 grams per cubic centimeter implies internal porosities ranging from about 10 to 30 percent.

10.
Science ; 268(5214): 1150-3, 1995 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-17840628

RESUMO

The abundance and distribution of iron on the moon is derived from a near-global data set from Clementine. The determined iron content of the lunar highlands crust ( approximately 3 percent iron by weight) supports the hypothesis that much of the lunar crust was derived from a magma ocean. The iron content of lower crustal material exposed by the South Pole-Aitken impact basin on the lunar farside is higher ( approximately 7 to 8 percent by weight) and consistent with a basaltic composition. This composition supports earlier evidence that the lunar crust becomes more mafic with depth. The data also suggest that the bulk composition of the moon differs from that of the Earth's mantle. This difference excludes models for lunar origin that require the Earth and moon to have the same compositions, such as fission and coaccretion, and favors giant impact and capture.

11.
Science ; 266(5192): 1835-9, 1994 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-17737076

RESUMO

In the course of 71 days in lunar orbit, from 19 February to 3 May 1994, the Clementine spacecraft acquired just under two million digital images of the moon at visible and infrared wavelengths. These data are enabling the global mapping of the rock types of the lunar crust and the first detailed investigation of the geology of the lunar polar regions and the lunar far side. In addition, laser-ranging measurements provided the first view of the global topographic figure of the moon. The topography of many ancient impact basins has been measured, and a global map of the thickness of the lunar crust has been derived from the topography and gravity.

12.
Science ; 266(5192): 1855-8, 1994 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-17737081

RESUMO

The distribution of elevations on the moon determined by Clementine deviates strongly from a normal distribution, suggesting that several geologic processes have influenced the topography. The hypsograms for the near side and far side of the moon are distinctly different, and these differences correlate with differences in composition as determined by Apollo orbital geochemistry, Clementine global multispectral imaging, and ground-based spectroscopy. The hypsograms and compositional data indicate the presence of at least five compositional-altimetric units. The lack of fill of the South Pole-Aitken Basin by mare basalts suggests poor production efficiency of mare basalt in the mantle of this area of the moon.

13.
Science ; 266(5192): 1858-62, 1994 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-17737082

RESUMO

Multispectral and topographic data acquired by the Clementine spacecraft provide information on the composition and geologic history of the Aristarchus region of the moon. Altimetry profiles show the Aristarchus plateau dipping about 1 degrees to the north-northwest and rising about 2 kilometers above the surrounding lavas of Oceanus Procellarum to the south. Dark, reddish pyroclastic glass covers the plateau to average depths of 10 to 30 meters, as determined from the estimated excavation depths of 100- to 1000-meter-diameter craters that have exposed materials below the pyroclastics. These craters and the walls of sinuous rilles also show that mare basalts underlie the pyroclastics across much of the plateau. Near-infrared images of Aristarchus crater reveal olivine-rich materials and two kilometer-sized outcrops of anorthosite in the central peaks. The anorthosite could be either a derivative of local magnesium-suite magmatism or a remnant of the ferroan anorthosite crust that formed over the primordial magma ocean.

14.
Science ; 252(5010): 1293-6, 1991 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-17842954

RESUMO

Near-infrared spectra of a bright and a dark thermal emission feature on the night side of Venus have been obtained from 2.2 to 2.5 micrometers (microm) at a spectral resolution of 1200 to 1500. Both bright and dark features show numerous weak absorption bands produced by CO(2), CO, water vapor, and other gases. The bright feature (hot spot) emits more radiation than the dark feature (cold spot) throughout this spectral region, but the largest contrasts occur between 2.21 and 2.32 microm, where H(2)SO(4) clouds and a weak CO(2) band provide the only known sources of extinction. The contrast decreases by 55 to 65 percent at wavelengths longer than 2.34 microm, where CO, clouds, and water vapor also absorb and scatter upwelling radiation. This contrast reduction may provide direct spectroscopic evidence for horizontal variations in the water vapor concentrations in the Venus atmosphere at levels below the cloud tops.

15.
Br J Psychiatry ; 151: 550-2, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3447674

RESUMO

Two cases of catatonic stupor are described due to presumed encephalitis lethargica. Catatonic and obsessional phenomena in the setting of a depressive psychosis associated with a movement disorder may constitute a post-encephalitic syndrome.


Assuntos
Catatonia/etiologia , Encefalite por Arbovirus/complicações , Adolescente , Adulto , Catatonia/terapia , Transtorno Depressivo/complicações , Eletroconvulsoterapia , Humanos , Masculino , Transtorno Obsessivo-Compulsivo/complicações
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