Effects of corn processing and cattle size on total tract digestion and energy and nitrogen balance

This study used 18 calves (295 ± 29 kg) and 18 yearlings (521 ± 29 kg) fed whole, cracked or steam-flaked corn (SFC) to evaluate nutrient digestion and energy balance across different types of processed corn and sizes of cattle. Cattle were fed a diet comprised of 75% corn (DM-basis) from whole, cracked or SFC to 2.5-times maintenance energy requirements. Subsequently, cattle were placed in individual stanchions and urine and feces was collected together with measures of gas production via indirect calorimetry. Data were analyzed using the MIXED procedure of SAS. There was no interaction of corn processing and cattle size (P ≥ 0.40). Time spent ruminating (min/d) and rumination rate (min/kg DM intake; DMI) was not affected by corn processing or cattle size. Eating rate (min/kg DMI) was faster (P < 0.01) for yearlings compared to calves. Total tract starch digestion was greatest (P = 0.01) for cattle fed SFC (97.5%), intermediate in cattle fed cracked (92.4%) and least in cattle fed whole corn (89.5%). Dietary digestible energy and metabolizable energy (Mcal/kg DMI) were greater (P ≤ 0.05) for cattle fed SFC compared to cracked or whole. A greater proportion of digestible energy was lost to heat production (P = 0.01) in cattle fed whole corn compared to cracked and tended to be greater (P = 0.08) in cattle fed SFC than cracked. Conversion of digestible energy to metabolizable energy in this study was more closely related to a dynamic model used to estimate metabolizable energy of feeds to dairy cows than to a linear model used to predict metabolizable energy of feeds to beef cattle. If library estimates of net energy for maintenance are correct, then retained energy (Mcal/d) should have been similar between each type of processed corn; however, retained energy was greater (P < 0.01) for cattle fed cracked compared to whole corn and tended to be greater (P = 0.06) compared to SFC. Yet, observed amounts of net energy based on measures of retained energy were not different (P ≥ 0.60) between cracked and SFC. Nitrogen balance was not affected (P ≥ 0.30) by corn processing or cattle size, although cattle fed cracked had numerically greater (P ≤ 035) N retention. These data indicate that physical processing of corn provides greater net energy to cattle in comparison to whole corn.

Heat capacity of lithium tungstate single crystal by DSC calorimetry data in the temperature range of 319-997 K

The heat capacity of lithium tungstate single crystal (Li2WO4) was measured for the first time in the temperature range of 319-997 K. The experiments were carried out by DSC calorimetry. The Li2WO4 single crystal was first grown by low-temperature-gradient Czochralski technique with weight control. The temperature dependence of Li2WO4 heat capacity in the temperature range 319-997 K was monotonic. According to results of our studies, there were no phase transitions in Li2WO4 in the investigated temperature range.

Synthesis of Dense 1,2,3-Triazole Polymers Soluble in Common Organic Solvents

Aiming at synthesis of dense 1,2,3-triazole polymers soluble in common organic solvents, a new 3-azido-1-propyne derivative, i.e., t-butyl 4-azido-5-hexynoate (tBuAH), was synthesized and polymerized by copper(I)-catalyzed azide–alkyne cycloaddition (CuAAC) and Huisgen cycloaddition (HC). CuAAC polymerization produced poly(tBuAH) composed of 1,4-disubstituted 1,2,3-triazole units (1,4-units), whereas HC polymerization gave poly(tBuAH) composed of 1,4- and 1,5-disubstituted 1,2,3-triazole units (1,4- and 1,5-units). In HC polymerization, the fraction of 1,4-unit (f1,4) decreased with the permittivity of solvent used. Differential scanning calorimetry data indicated that the melting point of poly(tBuAH) increased from 61 to 89 °C with increasing f1,4 from 0.38 to 1.0, indicative of higher crystallinity of poly(tBuAH) composed of 1,4-unit. Preliminary steady-state fluorescence study indicated that all the poly(tBuAH) samples of different f1,4 emitted weak but significant fluorescence in DMF. The maximum of fluorescence band shifted from ca. 350 to ca. 450 nm with varying the excitation wavelength from 300 to 400 nm.

Abstract 16900: Exertional Hemodynamics Among Patients With HFrEF Based on Resting HF Profile

Introduction: HFrEF can be classified by profiles A, B, C or L based on resting pulmonary capillary wedge pressure (PCWP) and cardiac output (Qc). We characterized exertional hemodynamics by HF profile. Methods: HFrEF patients (N=34) completed invasive exercise testing with Swan-Ganz and radial arterial catheterization on upright bicycle. Oxygen uptake was monitored by indirect calorimetry. Data were recorded at supine and upright rest, two exercise stages below ventilatory threshold (steady states 1 and 2), and peak exercise. Participants were stratified into HF profiles based on supine resting hemodynamics including PCWP and cardiac index (CI): Profile A (warm-dry) PCWP≤16mmHg, CI≥2.5L/min/m 2 ; Profile B (warm-wet) PCWP>16mmHg; CI≥2.5L/min/m 2 ; Profile C (cold-wet) PCWP>16mmHg; CI<2.5L/min/m 2 ; Profile L (cold-dry) PCWP≤16mmHg, CI<2.5L/min/m 2 . Results: Demographics are displayed in the table . Peak oxygen uptake (VO 2 ) was severely reduced in all participants ( figure 1 ). Throughout exercise, profile C and L patients had lower stroke volume and Qc, but higher (A-V)O2 difference than profiles A and B ( figure 2 ). Profile B and C patients had higher resting and exertional pulmonary arterial and PCWP filling pressures compared to profiles A and L. Conclusion: Exercise performance among HFrEF patients is not uniform. Exertional hemodynamics vary substantially based on HF profile.

Flame Retardant Polypropylenes: A Review

Polypropylene (PP) is a commodity plastic known for high rigidity and crystallinity, which is suitable for a wide range of applications. However, high flammability of PP has always been noticed by users as a constraint; therefore, a variety of additives has been examined to make PP flame-retardant. In this work, research papers on the flame retardancy of PP have been comprehensively reviewed, classified in terms of flame retardancy, and evaluated based on the universal dimensionless criterion of Flame Retardancy Index (FRI). The classification of additives of well-known families, i.e., phosphorus-based, nitrogen-based, mineral, carbon-based, bio-based, and hybrid flame retardants composed of two or more additives, was reflected in FRI mirror calculated from cone calorimetry data, whatever heat flux and sample thickness in a given series of samples. PP composites were categorized in terms of flame retardancy performance as Poor, Good, or Excellent cases. It also attempted to correlate other criteria like UL-94 and limiting oxygen index (LOI) with FRI values, giving a broad view of flame retardancy performance of PP composites. The collected data and the conclusions presented in this survey should help researchers working in the field to select the best additives among possibilities for making the PP sufficiently flame-retardant for advanced applications.

PyDSC: a simple tool to treat differential scanning calorimetry data

Herein, we describe an open-source, Python-based, script to treat the output of differential scanning calorimetry (DSC) experiments, called pyDSC, available free of charge for download at https://github.com/leonardo-chiappisi/pyDSC under a GNU General Public License v3.0. The main aim of this program is to provide the community with a simple program to analyze raw DSC data. Key features include the correction from spurious signals, and, most importantly, the baseline is computed with a robust, physically consistent approach. We also show that the baseline correction routine implemented in the script is significantly more reproducible than different standard ones proposed by proprietary instrument control software provided with the microcalorimeter used in this work. Finally, the program can be easily applied to large amount of data, improving the reliability and reproducibility of DSC experiments.