Increase In Reaction Time Research Articles

Enhanced thermoelectric power generation performance of mixed-phase FeS/FeS2 nanostructures by controlling the reaction time duration

Thermoelectric materials can convert heat energy into electricity and could be the future of sustainable energy demand. In the current work, we have successfully improved the thermoelectric performance of hydrothermally synthesized mixed-phase pyrite nanostructures. For this, samples with different FeS/FeS2 phase ratios were synthesized by controlling the reaction time duration. XRD data confirms the formation of mixed phases of FeS and FeS2, which increases with the increase in reaction time, while the Raman spectroscopy results verify the argument. Scanning electron microscope images represents the formation of nanoporous morphology. For thermoelectric properties, both the Seebeck coefficient (44–69 μV/°C) and electrical conductivity (33–48 S/cm) were found to be improved with the increase in reaction time (12–48h). This simultaneous enhancement in Seebeck coefficient and electrical conductivity was associated with the energy filtering effect at the crystal interface leading to the improvement in thermoelectric power factor to 2.28 × 10−5 Wm−1C−2 (at 25oC) for 48h sample.

Synthesis of sucrose ester through enzymatic esterification and stability analysis as food emulsifier

Sucrose ester can be synthesized enzymatically using fatty acid or fatty acid ester. The research has been carried out using methyl ester as a substrate in the synthesis of sucrose ester enzymatically. Initially, methyl ester was synthesized from crude palm kernel oil (off grade) through two-step reaction and obtained an ester content 96.5927%. Furthermore, the esterification reaction between methyl ester and sucrose was carried out using Candida antarctica as biocatalyst. This study aimed to determine the effect of reaction time and the ratio of Candida antarctica lipase on the yield of sucrose ester and to perform an emulsion stability test. The observation of esterification reaction time was carried out at 2, 4, 6, 8 and 10 (hours), while the ratio of Candida antarctica was carried out at 0.1; 0.2; 0.3; 0.4 and 0.5 (% w/w). The results showed that the increase in reaction time and the ratio of the lipase had an effect on increasing the yield of sucrose ester. Optimal synthesis of sucrose ester was obtained at reaction time of 10 hours and lipase enzyme ratio was 0.4% (w/w) with 90.45% of yield and emulsion stability at 487 seconds.

Preparation and formation process of high efficient and stable CsPbBr<sub>3</sub>-Cs<sub>4</sub>PbBr<sub>6</sub> nanocrystals with mixed phase

CsPbBr<sub>3</sub>-Cs<sub>4</sub>PbBr<sub>6</sub> dual-phase nanocrystals are prepared by adding the mixture ligand of oleylamine and tetradecyl-phosphonic acid (OLA-TDPA) to CsPbBr<sub>3</sub> perovskite nanocrystals through ligand post-treatment. The structure, the morphology, optical property and the stability of CsPbBr<sub>3</sub>-Cs<sub>4</sub>PbBr<sub>6</sub> dual-phase nanocrystals are characterized by X-ray diffraction, transmission electron microscopy (high-resolution TEM), UV-vis spectrophotometer, fluorescence spectrophotometer, and transient fluorescence spectrophotometer. The as-obtained nanocrystals have a high photoluminescence quantum yield of 78% and long fluorescence lifetime of 476 ns when prepared at the optimal molar ratio of CsPbBr<sub>3</sub>, TDPA and OLA (1∶1∶15). Moreover, the nanocrystal is quite stable at room temperature for at least 25 days, and has a good thermal stability in five heating-cooling cycles at temperature in a range between 293 K and 328 K. The formation of dual-phase nanocrystals go through two stages of surface passivation/dissolution and recrystallization to generate CsPbBr<sub>3</sub>-Cs<sub>4</sub>PbBr<sub>6</sub> nanocrystals. In the first stage (<i>t</i> ≤ 1 h), the m OLA-TDPA mixing ligand can form (RNH<sub>3</sub>)<sub>2</sub>PO<sub>3</sub> X type ligand and exchanges with [RNH<sub>3</sub>]<sup>+</sup>-[RCOO]<sup>–</sup> at the surface of CsPbBr<sub>3</sub> nanocrystals, which can effectively passivate surface defects by strong interaction with Pb<sup>2+</sup> and high ligand content at surface, thus improving the quantum yield and fluorescence life of CsPbBr<sub>3</sub> nanocrystals with spherical shape. In the second stage, with the increase of reaction time, PbBr<sub>2</sub> partially dissolves from the surface of CsPbBr<sub>3</sub> nanocrystals, then some CsPbBr<sub>3</sub> nanocrystals transform into lead-depleted Cs<sub>4</sub>PbBr<sub>6</sub> nanocrystals with hexagonal phase, thus improving the stability of nanocrystals. This work has a certain reference value for promoting the applications of high efficient and stable perovskite nanocrystals.

Attempting to counteract vigilance decrement in older adults with brain stimulation.

Against the background of demographic change and the need for enhancement techniques for an aging society, we set out to repeat a study that utilized 40-Hz transcranial alternating current stimulation (tACS) to counteract the slowdown of reaction times in a vigilance experiment but with participants aged 65 years and older. On an oscillatory level, vigilance decrement is linked to rising occipital alpha power, which has been shown to be downregulated using gamma-tACS. We applied tACS on the visual cortex and compared reaction times, error rates, and alpha power of a group stimulated with 40 Hz to a sham and a 5-Hz-stimulated control group. All groups executed two 30-min-long blocks of a visual task and were stimulated according to group in the second block. We hypothesized that the expected increase in reaction times and alpha power would be reduced in the 40-Hz group compared to the control groups in the second block (INTERVENTION). Statistical analysis with linear mixed models showed that reaction times increased significantly over time in the first block (BASELINE) with approximately 3 ms/min for the SHAM and 2 ms/min for the 5-Hz and 40-Hz groups, with no difference between the groups. The increase was less pronounced in the INTERVENTION block (1 ms/min for SHAM and 5-Hz groups, 3 ms/min for the 40-Hz group). Differences among groups in the INTERVENTION block were not significant if the 5-Hz or the 40-Hz group was used as the base group for the linear mixed model. Statistical analysis with a generalized linear mixed model showed that alpha power was significantly higher after the experiment (1.37 μV2) compared to before (1 μV2). No influence of stimulation (40 Hz, 5 Hz, or sham) could be detected. Although the literature has shown that tACS offers potential for older adults, our results indicate that findings from general studies cannot simply be transferred to an old-aged group. We suggest adjusting stimulation parameters to the neurophysiological features expected in this group. Next to heterogeneity and cognitive fitness, the influence of motivation and medication should be considered.

Dry reforming of methane over single-atom Rh/Al2O3 catalysts prepared by exsolution.

Single-atom catalysts often show exceptionally high performance per metal loading. However, the isolated atom sites tend to agglomerate during preparation and/or high-temperature reaction. Here we show that in the case of Rh/Al2O3 this deactivation can be prevented by dissolution/exsolution of metal atoms into/from the support. We design and synthesise a series of single-atom catalysts, characterise them and study the impact of exsolution in the dry reforming of methane at 700-900 °C. The catalysts' performance increases with increasing reaction time, as the rhodium atoms migrate from the subsurface to the surface. Although the oxidation state of rhodium changes from Rh(iii) to Rh(ii) or Rh(0) during catalysis, atom migration is the main factor affecting catalyst performance. The implications of these results for preparing real-life catalysts are discussed.

Rapid wet chemical synthesis of bioactive glass with high yield by probe sonication.

Bioactive glasses (BGs) are inorganic biomaterials which possess favourable properties for bone repair and regeneration. The biological properties of the BGs depend on their physical features. This manuscript describes a simple methodology for rapid synthesis of BG nanoparticles (NPs) with tailored physical properties using ultrasonic disruption produced by an ultrasonic probe. The ultrasonic probe generates stable and transient cavitation which increases the mass transfer and accelerates the chemical reaction. This approach is relatively green as it evades the use of the drastic acidic conditions required for hydrolysis. The prepared BG NPs were characterized by Fourier transform infra-red (FTIR) spectroscopy, Raman spectroscopy, scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD), particle size analysis (PSA), nitrogen adsorption/desorption and BET surface area analysis, X-ray photoelectron spectroscopy (XPS), inductively coupled plasma-optical emission spectrometry (ICP-OES), and in situ high temperature synchrotron XRD. The effects of ultrasonic irradiation time, and amplitude on the surface properties were investigated and the results confirmed that both parameters, especially amplitude, have significant effects on the physical properties of the prepared BG NPs. The XPS results showed that both, amplitude and time have a pronounced effect on the bridging and non-bridging oxygen atoms bonded to the Si centre in the BG samples, which play an important role in the bioactivity of the BG NPs. The in situ high temperature XRD patterns indicated a gradual phase transformation for the BG samples synthesized at different ultrasonic irradiation times and amplitudes. The TEM images showed that uniform nano-sized BG particles were obtained at 50% amplitude in only 10 minutes. A bimodal particle size distribution was observed with an increasing reaction time, up to 30 minutes, due to an increase in the formation of vortices at the interface where nucleation starts. All the prepared samples exhibited a glassy structure with the composition 70SiO2 : 25CaO : 5P2O5 and were highly bioactive. The proposed method would give a quick route for the synthesis of bioactive glasses and other ceramics with controlled physical properties.

Deep insights to explain the mechanism of carbon dot formation at various reaction times using the hydrothermal technique: FT-IR, 13C-NMR, 1H-NMR, and UV-visible spectroscopic approaches.

A well-explained mechanism for synthesizing carbon dots (CDs) is not yet explored and is still a subject of great debate and challenge. This study used a one-step hydrothermal method to prepare highly efficient, gram-scale, excellent water solubility, and blue fluorescent nitrogen-doped carbon dots (NCDs) with the particle size average distribution of around 5 nm from 4-aminoantipyrine. The effects of varying synthesis reaction times on the structure and mechanism formation of NCDs were investigated using spectroscopic methods, namely FT-IR, 13C-NMR, 1H-NMR, and UV-visible spectroscopies. The spectroscopic results indicated that increasing the reaction time affects the structure of the NCDs. As the hydrothermal synthesis reaction time is extended, the intensity of the peaks in the aromatic region decreases, and new peaks in the aliphatic and carbonyl group regions are generated, which display enhanced intensity. In addition, the photoluminescent quantum yield increases as the reaction time increases. The presence of a benzene ring in 4-aminoantipyrine is thought to contribute to the observed structural changes in NCDs. This is due to the increased noncovalent π-π stacking interactions of the aromatic ring during the carbon dot core formation. Moreover, the hydrolysis of the pyrazole ring in 4-aminoantipyrine results in polar functional groups attached to aliphatic carbons. As the reaction time prolongs, these functional groups progressively cover a larger portion of the surface of the NCDs. After 21 h of the synthesis process, the XRD spectrum of the produced NCDs illustrates a broad peak at 21.1°, indicating an amorphous turbostratic carbon phase. The d-spacing measured from the HR-TEM image is about 0.26 nm, which agrees with the (100) plane lattice of graphite carbon and confirms the purity of the NCD product with a surface covered by polar functional groups. This investigation will lead to a greater understanding of the effect of hydrothermal reaction time on the mechanism and structure of carbon dot synthesis. Moreover, it offers a simple, low-cost, and gram-scale method for creating high-quality NCDs crucial for various applications.

Structural, Morphological, and Magnetic Characterization of Iron Oxide Nanoparticles Synthesized at Different Reaction Times via Thermal Decomposition Method

Background: Superparamagnetic Iron Oxide Nanoparticles (SPIONs) were synthesized by the thermal decomposition method. Methods: In this work, the properties of the nanoparticles synthesized at different reaction times were investigated. Fourier Transformed Infrared Spectroscopy (FTIR) and thermal analysis were carried out to characterize oleate adsorbed on the surface of nanoparticles. Results: The oleate-coated surfaces were obtained for all samples, and the amount of oleate on the surfaces of the particles changed with the change in reaction time. The size, size distribution, and shape of SPIONs were determined by X-ray Diffraction (XRD), transmission electron microscopy (SEM), and Dynamic Light Scattering (DLS). It was seen that changing the reaction time affected the shape of the nanoparticles, but almost the same sized nanoparticles were obtained with the increase of reaction time. The sample's crystallite size of 12.5-14.2 nm achieved with XRD is in good agreement with the mean size of 15-16.4 that was obtained by TEM results. Maximum magnetic saturation of the sample was achieved at 3 h reaction time. Conclusion: The magnetic properties of iron oxide nanoparticles were characterized by Electron- Spin Resonance (ESR) and Physical Properties Measurement System (PPMS). All samples showed superparamagnetic behaviors at room temperature.

Effect of Proprioception Exercise versus Focused Regimen Exercise on Balance and Quality of Life in Subjects with Diabetic Neuropathy

Background: Diabetic peripheral neuropathy is a polyneuropathy that can cause damage to the peripheral nervefibers, sensorimotor and autonomic nervous system. Neuropathy causes somatosensory dysfunction of the lowerextremities, such as decreased ankle position and vibration sensations. The sensation of the skin on the feet andthe proprioceptive sense are two important factors in standing balance, postural control and coordination. As thiscondition progresses, this can lead to increased postural sway, gait disturbance, abnormal neuromuscular controland increased reaction time leading to falls in balance impaired patients.Objective: To determine the effect of proprioception exercise versus focused regimen exercise on balance andquality of life in subjects with diabetic neuropathy.Methods: 20 Subjects with diabetic neuropathy of both genders, in the age group of 40 – 60 years were convenientlyassigned into 2 groups. Group A (n = 10) received Proprioception exercise and Group B (n = 10) received Focusedregimen exercise, 3 sessions a week for 8 weeks. Balance and quality of life were evaluated with Berg Balance Scaleand SF – 36 Survey questionnaire.Results: The difference in the post-test mean scores of group A and group B in Berg Balance Scale was 32 and 28.3and SF – 36 Survey questionnaire was 61.4 and 56.6 respectively. The result showed a significant improvement inGroup A than in Group B at p < 0.0001.Conclusion: Therefore, the study concludes that the Proprioception exercise training is better managementto improve balance and quality of life in subjects with diabetic neuropathy.

The correlation of sulfonation reaction kinetics with the degree of sulfonation (DS) and its effects on microstructure and morphology of electrospun fibers for the membrane of fuel cells.

Sulfonation is among the frequently used surface modification methods to endow new surface properties on polymer fibers. Direct sulfonation is the simplest chemical modification via incorporation of sulfonate functional groups onto fibers' surfaces at ordinary conditions. However, the process of functionalization compromises other properties of the electrospun membrane due to the extent of sulfonation reaction that occurred. This study was carried out to determine the effects on microstructure and morphology of crosslinked electrospun polybenzoxazine (PBz) fibers by correlating the reaction kinetics using a specific reaction parameter with the degree of sulfonation (DS). The kinetics of sulfonation reaction for PBz fibers is an electrophilic-based, first-type substitution mechanism where only one sulfonic acid (-SO3H) group is attached to each of the repeating units in the aromatic structure of PBz under ordinary conditions. From a previous study, the rate of change of ion exchange capacity (IEC) was derived as a logarithmic correlation that increased rapidly for some time and became constant. This study employed the derived empirical relationship based on reaction kinetics to correlate the degree of sulfonation (DS) with IEC at varying reaction time. DS was calculated as 55%, 66% and 77%, for 3, 6 and 24 h, respectively. The maximum IEC of 2.71 with the corresponding DS of 100% was obtained theoretically but since sulfonation reaction kinetics at ordinary conditions proceeds at slower phase, it can only attain 86% DS with maximum IEC of 2.44 at a calculated time of 48 h. Sulfonation was confirmed by the functional groups present in the structural composition of PBz fibers using ATR-FTIR which were quantified based on the absorbance in the IR spectra showing an increased peak height with increased reaction time for the first 6 h. Morphological analyses using SEM images revealed an increase in fiber diameter with increased sulfonation time. In addition, the higher reaction time showed the effects of longer acid exposure which compromised the fibers' structural integrity with the presence of broken fibers and defects on fibers' surfaces after 24 h. The electrospun PBz fibers sulfonated for 6 h achieved the highest IEC value with DS of 66% which was enough to attain the balance of degree of sulfonation with electrochemical and morphological properties.

Evaluation of Antinociceptive Activity of Ficus Religiosa Root Extract in Swiss Albino Mice

Background 
 Ficus religiosa, commonly known as peepal, is widely distributed in Indian subcontinent. It has been used as an antiepileptic, aphrodisiac, analgesic, anti-inflammatory and laxative in traditional medicine.
 Objective To explore the analgesic effect of aqueous root extract of Ficus religiosa using thermal and chemical models of pain in swiss albino mice.
 Method The aqueous aerial root extract of Ficus religiosa was prepared using soxhlet apparatus. The anti-nociceptive effect of the extract at doses of 50 and 100 mg/kg was evaluated using peripheral (acetic acid-induced abdominal writhing), spinal (tail flick) and supra-spinal (hot plate) behavioral models of pain. All data were presented as Mean ± SEM. Statistical differences between Ficus religiosa (50 and 100 mg/kg) and standard control groups were evaluated using Mann-Whitney U test.
 Result There was significant dose dependent increase in the mean reaction time compared to the vehicle control in hot plate and tail- flick test. In acetic acid induced writhing test, mice treated with Ficus religiosa (50 and 100 mg/kg) exhibited significant dose-dependent decrease in the mean number of writhes (57.45% and 79.20% respectively) compared to the vehicle control. The activity of Ficus religiosa extract at doses of 50 and 100 mg/kg was equipotent to Standard control (Morphine and Indomethacin) used in different test models.
 Conclusion The extract of Ficus religiosa possesses both central and peripheral analgesic activity thus validating the traditional use of this plant in the management of pain.

The Ameliorative Effect of Thymoquinone on Vincristine-Induced Peripheral Neuropathy in Mice by Modulating Cellular Oxidative Stress and Cytokine.

Thymoquinone (TQ), an active constituent of Nigella sativa, has been reported to exert a broad spectrum of pharmacological effects, including neuroprotective, anticancer, anti-inflammatory, antidiabetic, antiepileptic, antioxidant, and other modulatory roles in inflammation in experimental studies. The present study aims to evaluate the potential effects of TQ on vincristine-induced neuropathy in mice, as well as the possible role of oxidative stress, and pro- and anti-inflammatory cytokine in neuropathy development. A Swiss strain of male albino mice were randomly divided into seven groups, comprising of five animals each. Vincristine sulfate (0.1 mg/kg, i.p.) was administered for 10 consecutive days for the induction of peripheral neuropathy. The animals received their respective treatment of TQ (2.5, 5, and 10 mg/kg, p.o.) and pregabalin (10 mg/kg, p.o.) concurrently with vincristine for 10 days followed by 4 days post treatment. The animals were assessed for pain and related behavior on day 7 and 14 using hot and cold plates, and a rotarod test. TQ preventive treatment attenuated vincristine induced neuropathy in a dose dependent manner evidenced as a significant (p < 0.001) increase in reaction time on the hot plate and the cold plate, and a fall off time on the rotarod test. Further, TQ preventive treatment resulted in a significant (p < 0.001) reduction in the number of flinches and duration of paw elevation in a formalin test. Preventative treatment with TQ abolished the vincristine-induced rise in malondialdehyde and glutathione depletion in sciatic nerve tissue, as well as the blood IL-6 levels. In conclusion, TQ at 2.5, 5, and 10 mg/kg dose produced significant attenuation of neuropathic pain induced by vincristine which may be due to its antinociceptive, antioxidant, and anti-proinflammatory activity.

Phosphorus diffusion at the interface between 2CaO·SiO2 and CaO–SiO2–FeO–P2O5 slag

ABSTRACT The reaction behaviour of solid 2CaO·SiO2 (C2S) in steel slag is of great interest during the hot-metal dephosphorization process. In the present work, C2S samples were prepared and interfaced with steel slag to investigate the phosphorus diffusion behaviour at the interface of C2S at 1723K at the onset of the slag melting. The results showed that the phosphorus diffusion from the slag to C2S was very rapid with a significant diffusion coefficient of 4.44 × 10−9 m2·s−1. Phosphorus-enriched phases were formed continuously with increasing reaction time. As the reaction time increases, the composition of the diffusion layer becomes closer to 3CaO·P2O5 (C3P) and farther away from the C2S. The results indicate that a hot-metal dephosphorization process with much higher efficiency can be achieved by the careful selection of the interface characteristics between the C2S and steel slag.

Varying the hydrophobicity of humic matter by a phase-transfer-catalyzed O-alkylation reaction

An O-alkylation reaction catalyzed by tetrabutylammonium hydroxide (TBAH) as a phase-transfer agent was applied to a humic acid (HA) to modify its hydrophobic properties. The carboxyl and hydroxyl functional groups of HA acted as nucleophiles in substitution reactions (Sn2) with methyl iodide, pentyl bromide and benzyl bromide added in amounts equimolar to 20, 60 and 80% of HA total nucleophilic sites. The occurrence of O-alkylation was shown by DRIFT spectrometry, NMR spectroscopy, High Performance Size Exclusion Chromatography (HPSEC) and elemental analysis of reaction products. DRIFT spectra showed changes in C–H stretching and bending regions following the insertion of methyl and pentyl groups, while the incorporation of benzyl groups revealed the characteristics aromatic C–H stretching bands. Both liquid- and solid-state NMR spectra revealed characteristic signals for alkyl/aryl esters and ethers. HPSEC chromatograms of alkylated materials invariably displayed an increase in hydrodynamic volume in respect to the original HA, thereby suggesting that the enhanced hydrophobicity conveyed further associations among humic molecules. Analytical, HPSEC and spectroscopic results suggest that benzylation was the most effective reaction at all percentages of HA total nucleophilicity, followed, in the order, by pentylation and methylation, The benzylation reaction was used to improve reaction and work-up conditions and show that HA could be efficiently alkylated also with substantial reduction of TBAH amount, with no THF addition, increase of reaction time and of washing cycles to remove catalyst impurities. These findings indicate that the hydrophobicity of humic substances can be modulated through a mild O-alkylation reaction under a phase-transfer catalysis according to the extent of exposed HA nucleophilic sites. Such a structural modification of humic matter may have multiple chemical, environmental and biological applications.

Synthesis of LiNi0.6Co0.2Mn0.2O2 Using Supercritical Carbon Dioxide as a Cathode Material for Lithium‐Ion Batteries

AbstractA supercritical carbonation method for the preparation of lithium‐ion battery precursor (Ni0.6Co0.2Mn0.2CO3) is proposed. With appropriate selection of reaction temperature, pressure and pH, a desirable stoichiometry of transition metal ratio (6 : 2 : 2) can be achieved. The precursor synthesis time plays a significant role in the battery performance as the transition metal ion distributions become more uniform with increasing reaction time. This results in a more stable layered structure, lower cation mixing level, higher electrochemical reversibility, and lower impedance. The battery made of the precursor prepared under the best synthesis conditions can achieve a discharge capacity of 174.2 mAh g−1 in the first cycle and a capacity retention of 93.0 % after 50 cycles using a current density of 60 mA g−1. This study proves the feasibility of using supercritical carbon dioxide as the reagent for the coprecipitation of lithium‐ion battery precursor Ni0.6Co0.2Mn0.2CO3. Furthermore, this method can possibly be applied to the synthesis of other carbonate‐based materials.

Improved gonadal sperm reserves, growth performance, and antioxidant capacity of maturity V-line rabbits fedVespa oriental meal

Insects continue to receive considerable interest as a potential nutrient source and as nutraceuticals. In this study, the effects of diets containing 25 and 50% ofVespa orientalis meal (VOM) as a replacement for soybean meal (control: 100%), on the reproductive potential of 90-day-old V-line male rabbits (average weight: 1.06±0.03 kg) were investigated. Bucks fed the 50% VOM diet demonstrated the highest increase in body weight, reaction time, and testicular weight at maturity, and their gonadal sperm reserves (GSR) increased significantly (P<0.001) compared with those of other experimental groups. GSR in the testis was significantly (P<0.001) higher in rabbits fed a diet containing VOM than the control group. Epididymal sperm reserves in caput, corpus, and cauda increased significantly (P<0.001) as the percentage of VOM increased in the diets of bucks. The daily sperm production per gram in the testis of bucks fed with diets containing VOM improved significantly (P<0.05; by 39.67 and 62.13% when provided with diets containing 25 and 50% VOM, respectively) compared with that in the control group. Similarly, testosterone and follicle-stimulating hormone levels were significantly (P<0.05) higher in the VOM-fed groups than in the control group. However, luteinising hormone levels declined (P<0.05) in the VOM- provided groups than in the control group. Supplementation with different VOM levels significantly (P<0.001) enhanced the serum total antioxidant capacity, and glutathione peroxidase and superoxide dismutase activities, and decreased the serum malondialdehyde levels compared with the control group. Serum biochemical traits, including protein and lipid profiles and glucose concentration, were significantly improved in bucks fed with VOM-supplemented diets. In conclusion, dietary VOM supplementation promotes the daily sperm production, testicular sperm reserves, sexual hormone production, and antioxidant capacity of V-line bucks.

Sintesis Nanopartikel Tembaga dari Larutan CuSO4.5H2O dengan Menggunakan Ekstrak Getah Merkubung ( Macarangan Gigantea)

The synthesis of copper nanoparticles in this study used a reducing agent from the extract of mercurd gum with a solution of CuSO4.5H20. The results of the synthesis of copper nanoparticles using the extract of mercurd gum resulted in the color of the solution becoming clear greenish. The reaction time greatly affects the formation of copper nanoparticles, it can be seen visually that after 5 minutes the reaction shows a color change from clear to clear greenish and a lot of precipitate is formed. As the reaction time increases, the solution gets darker. The color of the copper nanoparticle solution tends to be clear to clear greenish, the clear color will continue to increase with the length of reaction time. In XRD analysis of Cu which has been synthesized from 0.01 M mercury extract solution. It can be seen that Cu nanocrystals have been formed which are indicated by the appearance of peaks at 2q : 18.76˚, 22.24˚, and 23.99, The results of the Scanning Electron Microscopy analysis, the results of the SEM analysis in the study show that the particle sizes produced are different from one another and the distribution of particles is uneven, there are many particles that accumulate into chunks larger than other particles so that the size is not uniform and to form agglomerations. This is because the particle growth is very fast and UV-vis Confirmation of the formation of nanoparticles can be known through UV-Vis spectrophotometer observations by measuring the absorbance value in time intervals.

Characteristics and anti-inflammatory effects of the enzymatically extracted polysaccharides of Sargassum fulvellum using crude enzyme from Shewanella oneidensis PKA 1008

Alginic acid is a polysaccharide obtained from brown algae, and its oligosaccharide has various functions such as antiviral, antitumor, immunoregulation, and antioxidant. However, because of its high viscosity, numerous studies have degraded the alginic acid by enzymes to improve its utilisation. In the present work, we characterised Sargassum fulvellum enzymatic extract (SFEE) using polysaccharide-degrading enzyme obtained from Shewanella oneidensis PKA 1008, and investigated its anti-inflammatory potential. S. fulvellum powder and crude enzyme were mixed at a ratio of 1:1 (v/v), and reacted at 30°C for 0 - 48 h to obtain the optimum degrading time. The changes in pH, colour, reducing sugar, and viscosity of SFEE were determined. The anti-inflammatory activity of SFEE was confirmed by measuring the expression level of nitric oxide (NO) and pro-inflammatory cytokines (IL-6, TNF-α, and L-1β) in RAW 264.7 macrophage cell line. The reducing sugar content was found to increase 2.75-fold at 24 h as compared to that at the initial reaction point, but pH and viscosity decreased significantly with increasing reaction time. SFEE showed a high inhibitory effect on the levels of NO and pro-inflammatory cytokines. SFEE thus has great potential for development as a functional food and therapeutic material owing to its anti-inflammatory effect.

Contribution of semantic context to bilingual processing

Aims: This paper seeks to determine the degree to which bilinguals and monolinguals use the semantic information available to them to activate semantically related lexical associates and facilitate processing. Design: We conduct a visual word masked priming task with 300 pairs of words that differed in forward strength of association in English-dominant early-acquiring and late bilinguals and monolinguals. We measured the reaction time for participants who completed a semantic judgment. Data and Analysis: Reaction times from 34 college-aged bilinguals and 28 monolinguals were analyzed with a series of analyses of variance (ANOVAs). The coefficient of variation (CV), a measure of efficiency, was calculated and used to compare speaker groups. Conclusions: Results indicated bilinguals were generally slower than monolinguals and did not display a benefit of additional semantic context on reaction time speed. The increase of semantic information in highly associated word pairs compared to unassociated word pairs did not increase reaction time in bilinguals to the same degree as it did in monolinguals. Comparing CV values indicate that the speaker groups were processing semantic information with approximately equal efficiency, although both groups were processing at different speeds. Originality: This study expands on previous research exploring the effect of semantic relations across three word strengths conditions and using visual pairs in a masked priming paradigm using predominantly English-dominant bilinguals. Significance: The findings indicate that even early-acquiring bilinguals may not be using meaning-related information to activate semantic associates in the same way as monolinguals. Such differences with word-level processing and activation may contribute to bilinguals’ differences and delays in sentence processing tasks.

Co-Enzymes with Dissimilar Stabilities: A Discussion of the Likely Biocatalyst Performance Problems and Some Potential Solutions

Enzymes have several excellent catalytic features, and the last few years have seen a revolution in biocatalysis, which has grown from using one enzyme to using multiple enzymes in cascade reactions, where the product of one enzyme reaction is the substrate for the subsequent one. However, enzyme stability remains an issue despite the many benefits of using enzymes in a catalytic system. When enzymes are exposed to harsh process conditions, deactivation occurs, which changes the activity of the enzyme, leading to an increase in reaction time to achieve a given conversion. Immobilization is a well-known strategy to improve many enzyme properties, if the immobilization is properly designed and controlled. Enzyme co-immobilization is a further step in the complexity of preparing a biocatalyst, whereby two or more enzymes are immobilized on the same particle or support. One crucial problem when designing and using co-immobilized enzymes is the possibility of using enzymes with very different stabilities. This paper discusses different scenarios using two co-immobilized enzymes of the same or differing stability. The effect on operational performance is shown via simple simulations using Michaelis–Menten equations to describe kinetics integrated with a deactivation term. Finally, some strategies for overcoming some of these problems are discussed.