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Effect of polyol supplementation in forage-based total mixed rations on in vitro rumen gas production and fermentation in beef cattle
No full textThe study evaluated the effects of a polyol blend (equal parts xylitol, arabinitol, and sorbitol) added to beef cattle total mixed rations (TMR) on in vitro rumen fermentation, total gas production, digestibility, and organic acid profiles. Polyols were supplemented at 0, 2, 4, 8, and 12% of dry matter. Results showed no significant differences in total gas production, metabolic energy, lactation net energy, or organic matter digestibility (OMd) between polyolsupplemented groups and the control (P < 0.05). However, the addition of 2, 4 and 8% polyols increased in vitro rumen pH (P < 0.05). All polyol levels reduced the proportions of acetic acid (AA), butyric acid (BA), propionic acid (PA), isobutyric acid (IBA), valeric acid (VA), iso-valeric acid (IVA), and branched short chain fatty acids (BSCFA) in total short-chain fatty acids (T-SCFA), while only 12% supplementation elevated straight-chain SCFA concentrations (P < 0.05). Overall, polyol addition at 2, 4, 8, and 12% did not significantly alter in vitro rumen fermentation parameters (total gas production, OMd, energy values and SCFAs) in beef cattle TMR. However, the increase in rumen fluid pH observed with moderate polyol doses (2–8%) suggests a potential buffering effect, which may be beneficial in starch-rich diets used during intensive fattening or early lactation in dairy cattle
Measuring the impact: Severity of harm from laboratory errors in 195 tests
No full textObjectives: This study aimed to objectively assess the potential severity of harm associated with erroneous results in 195 laboratory tests by surveying 514 specialist physicians and medical biochemistry experts. Methods: The survey obtained participants’ (75 medical biochemists, 439 clinicians) opinions on severity of harm for the erroneous results of 195 tests. The comprehensive list of errors and their effects on test results were obtained from the literature, and then matched with severity of harm scores, from 1 (negligible effect) to 5 (life-threatening injury/death), obtained from the survey responses. Results: Participants perceived tests such as cardiac biomarkers, blood gases, coagulation parameters (activated partial thromboplastin time, prothrombin time, international normalized ratio, and dimerized plasmin fragment D), critical ions (potassium, sodium), toxic trace elements (lead, mercury), and specific serum drug levels (lithium, digoxin) to have a greater potential for patient harm in case of errors. Medical biochemistry specialists assigned higher severity scores to some laboratory tests, including total bilirubin, pseudocholinesterase, platelet indices, and some drug levels (cyclosporine, methotrexate, vancomycin). Conclusions: A substantial agreement (91%) was observed between medical biochemists and clinicians in terms of the most frequently chosen severity of harm score. The study provided objective severity scores and identified high-risk tests for targeted quality improvement
MOVPE Growth and Doping Optimization of n-AlGaAs Layers for Laser Diode Applications
No full textEpitaxial n-AlₓGa₁₋ₓAs layers, which form the basis of semiconductor laser structures, play a critical role in both optical and electrical performance of the device. These layers provide electron injection into the active region and at the same time act as optical waveguides, allowing efficient steering of the laser light. Since Al concentration and doping levels have a direct effect on fundamental properties such as band gap, carrier density and resistive losses, it is of great importance to meticulously optimize these parameters. In this study, n-AlₓGa₁₋ₓAs layers grown epitaxially on GaAs substrate by MOVPE (Metal Organic Vapor Phase Epitaxy) method were processed with n-type doping process applied by using SiH₄ precursor and the effects of increasing Al concentration on doping density were investigated in detail. The obtained results show that when Al concentration is above 30%, no significant increase in doping density is observed despite the maximization of SiH₄ flow. Furthermore, the data obtained with Hall and ECV (Electrochemical Capacitance Voltage) measurements provided consistent results at low Al ratios, while significant differences were observed above 0.2 Al ratio. This comprehensive analysis reveals the current limitations in n-type doping processes and precise control of Al concentration, while providing a more in-depth interpretation by systematically comparing the obtained results with the data reported in the literature
Synthesis of (2R,3S)-2-(3,4-Dihydroxy phenyl)chroman-3,5,7-triol Derivative Boron Compounds: Antioxidant, Enzyme, Antimicrobial, and Antibiofilm Activities
No full text(2R,3S)-2-(3,4-dihydroxyphenyl)chroman-3,5,7-triol compound corresponds to catechin, which is from the flavanol class of flavonoids and has many pharmacological effects such as anticarcinogenic, antioxidant, dermatological, antihypertensive, antiviral, antimutagenic, antidiabetic. The aim of this study is to investigate novel drug candidates for several human diseases composed of catechin and boronic acid derivatives. Catechin was modified by various types of boronic acid compounds. In the derivatization experiment, phenyl boronic acid, 6-methoxy naphthalene boronic acid, 1,4-phenyl diboronic acid, 3-formyl phenyl boronic acid, and 4-methoxy-3-formyl phenyl boronic acid, 4-methoxy phenyl boronic acid were firstly used to modify catechin. The newly obtained compounds were structurally elucidated by 1H NMR, 13C NMR, FTIR, and LC-MS spectral techniques. All novel derivatives were examined for antioxidant (with particular methods such as ABTS, DPPH, and CUPRAC), enzyme, and antibiofilm activities. Most compounds were determined to be more active or effective than those standard compounds. Among all derivatives, CB-2 showed the highest inhibition of enzymes and the highest antioxidant activities. Biological results revealed that the boronic-modified compounds could be designed as potential antioxidants, enzymes, antimicrobials, and antibiofilm agents
