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Introducción. Los microorganismos de montaña (MM) son un insumo fundamental para la producción orgánica/ecológica en Costa Rica. Su uso genera preguntas relacionadas con el procedimiento para las activaciones líquidas, que presenten las mayores poblaciones microbianas. Objetivo. Evaluar factores clave que afectan la calidad de la fase líquida de MM, tales como el tiempo de activación, aireación, presencia de nutrientes, entre otros. Materiales y métodos. Se evaluaron factores asociados con las activaciones líquidas, tiempo de activación, disponibilidad de aireación, dosis de MM sólido, dosis de melaza y la adición de nutrientes inorgánicos solubles (K) e insolubles (P). Se determinaron poblaciones de bacterias, hongos filamentosos, bacterias fijadoras de nitrógeno (FN), microorganismos solubilizadores de fósforo (SP), lactobacilos (Lac) y levaduras (Lev), así como pH y P en solución. Los datos se sometieron a la prueba de Shapiro-Wilks. Las variables que no presentaron normalidad fueron evaluadas según Kruskal Wallis y las normales con ANDEVA y LSD Fisher (p

This study examined internal and external quality traits of organic and cage-system table eggs in different household storage conditions. Baseline values for internal and external quality traits were obtained for 60 fresh eggs per production system, and the remaining eggs were then divided into six groups according to storage conditions. Eggs were kept at two different temperatures (room temperature and refrigerator temperature) with three subgroups (with stretch-wrap, without stretch-wrap and washed). At 7, 14, 21, and 28 days, 15 eggs were selected from each group, and internal and external quality traits as well as weight loss were measured. Lowest egg weight loss occurred in eggs stored in the refrigerator with stretch-wrap (0.99%, p

Groundwater is essential for the sustainable development of the Guanzhong Basin, China, and its quality is mainly controlled by hydrogeochemical processes and anthropogenic pollution. This study used statistical and multivariate statistical analysis approaches to recognize the hydrogeochemical processes and affecting factors of groundwater in the central part of the Guanzhong Basin. Correlations among 14 hydrochemical parameters were statistically examined. Principal component analysis (PCA), factor analysis (FA), and hierarchical cluster analysis (HCA) techniques were applied to analyze the physicochemical variables to understand the affecting factors of groundwater quality in the study area. The correlation analysis results indicate that cation exchange is the dominant process affecting the concentration of Na+ and Ca2+ in the groundwater. Both the PCA and FA indicate that minerals dissolution/precipitation and human activities are the key factors that affect groundwater quality. All parameters except CO32- and pH increase from C1 to C4 obtained through the Q mode HCA. C4 has a hydrochemical type of SO4-Na·K, indicating that the sample of this cluster is primarily influenced by anthropogenic processes.

Wettability alteration seems to be the main physicochemical process during low salinity water injection in carbonate formations. A pH increase due to calcite dissolution during low salinity water i...

Injecting low saline water is one of the practices used to improve hydrocarbon production that has recently significantly grown due to its advantages over seawater and chemical flooding. Although many theories and mechanisms have been provided on how additional oil recovery has been achieved utilizing low salinity waterflooding, the principle fundamentals of the mechanism(s) are still ambiguous. This article investigates the potential use of low salinity waterflooding (LSWF) to improve oil production from a sandstone formation. A 3D field-scale model was developed using Computer Modeling Group ( generalized equation-of-state model simulator) based on a mature oil field data. The developed model was validated against actual field data where only 8% deviation was observed. Simulation analysis indicated that multi-component ion exchange is a key factor to improve oil production because it alters rock wettability from oil-wet to water-wet. Simulation sensitivity studies showed that low salinity water flooding provided higher oil production than high water salinity flooding. Moreover, simulation showed early breakthrough time of low salinity water injection can provide high oil recovery up to 71%. Therefore, implementing LSWF instantly after first stage production provides recovery gains up to 75%. The determined optimal injected brine composition concentration for Ca 2+ , Mg 2+ and Na + are 450, 221, and 60 ppm, respectively. During LSWF, a high divalent cations and low monovalent cations’ concentration can be recommended for injected brine and formation aquifer for beneficial wettability alteration. Simulation also showed that reservoir temperature influenced the alteration of ion exchange wettability during LSWF as oil recovery increased with temperature. Therefore, high temperature sandstone reservoirs can be considered as a good candidate for LSWF. Cited as : Ben Mahmud, H., Mahmud, W.M., Arumugam, S. Numerical investigation of optimum lons concentration in low salinity waterflooding. Advances in Geo-Energy Research, 2020, 4(3): 271-285, doi: 10.46690/ager.2020.03.05

Cellulose nanofibrils (CNFs) prepared from wood biomass are promising candidates to replace oil-based materials in, for example, packaging applications. However, CNFs' affinity for water combined with their small size leads to very slow and energy-demanding processes for handling and removal of water. To a large extent, this is the major roadblock that prevents a feasible production of dry CNF-based materials on an industrial scale. In this work, self-fibrillating fibers (SFFs) from wood, where the fibrils can be liberated by external stimuli, were prepared via sequential TEMPO and periodate oxidation reactions. Papers made from these modified fibers using conventional laboratory papermaking methods were then in situ nanofibrillated via a modest pH increase. With a dewatering time of less than 10 s for a 3 g/L dispersion, SFFs represent a major improvement over conventional CNF nanopapers that take approximately 6 h to dewater. Moreover, 100 g/m2 nanopapers obtained through in situ fibrillation exhibited comparable, if not superior, properties to those reported for conventionally made CNF films. A tensile strength of 184 MPa, a Young's modulus of 5.2 GPa, a strain at break of 4.6%, 90% optical transmittance, and an oxygen permeability of 0.7 cm3 μm m-2 d-1 kPa-1 at 50% RH were measured for SFF nanopapers. Furthermore, in situ nanofibrillation of the SFFs can also be achieved from already dried papers, facilitating numerous possibilities in terms of logistics and handling for an industrial scale-up and transportation of nanomaterials. Overall, stimuli-induced SFFs indeed enable a rapid production of strong, transparent, gas barrier nanopapers, which likely can be industrially scaled up and eventually compete with the oil-based plastics in the market for packaging materials. QC 20220406Correction in DOI: 10.1021/acs.biomac.0c00040

Electro-activated alkaline (basic) solution known as catholyte has been reported to have a number of unique properties. The changes in the pH and alkalinity of the catholyte were monitored in the current study. A full-factorial design was applied in order to examine the effects of current, time of treatment, and salt concentration on the electro-activated solutions treated in 4 types of configurations. Two configurations were constructed as three-compartment cells with chambers separated by anion exchange membrane (AEM) and cation exchange membrane (CEM) with different dispositions in the cell. The other two configurations were two-compartment cells with chambers separated by either an AEM or a CEM. For pH increase, time was the most significant factor, whereas for the alkalinity the cell configuration had a significant impact. Thus, when CEM was used to separate central and cathodic compartments in a three-cell reactor, or anodic and cathodic compartments in a two-cell reactor only current and time were found to be highly significant. On the other hand, when the AEM was used the salt concentration appeared to be an important factor too. Maximum values for pH (pH 12) and alkalinity (25.46 ± 0.31 mmol/L) were obtained after 60 min of treatment and 0.2 A current, and regardless of NaCl concentrations when CEM was used, whereas maximum values for the AEM membrane were achieved only with maximum NaCl concentration of 1 M. Despite highly alkaline medium (pH ~ 12) the strength of the solution was comparable to dilute NaOH solution (~0.03 M).

Acid mine water causes environmental problems due to its high acidity caused by its high sulfate content which can disturb the life of organisms. This problem can be resolved by utilizing sulfate-reducing bacteria (SRB) abundantly found in sediments. The purpose of this research is to study the use of estuary sediments as a source of SRB inoculums to reduce sulfate in acid mine water. Thebioremediation treatment of acid mine water is carried out in a column bioreactor, with treatment T1 comprising of sediment and compost, and then comparing it to treatments T2 of sediment, T3 of compost, and T4 as the control treatment of only acid mine water. Results show that treatment T1 was able to reduce sulfate concentrations by 78%, compared to T2 by 56%, T3 by 21% and T4 by 5%. The reduction of sulfate was followed by increases in pH where T1 reached a pH value of 7.1, compared to treatments T2 andT3 which had pH values less than 5.5, whereas treatment T4 had a pH of 2.2. The reduced sulfate and increased pH was also followed by an increase of SRB growth, especially in T1. Estuary sediments as a source of SRB inoculums can be used in the bioremediation of acid mine water by adding compost to maximize the process of sulfate reduction and pH increase.

Low methane (CH4) emissions from sheep fed forage rape (Brassica napus) might be related to low ruminal pH value. In this study, sodium carbonate (Na2CO3: SC) was supplemented to the diet to alter ruminal pH for evaluation of its role in CH4 emissions from sheep fed forage rape. Fourteen intact and eight fistulated Romney sheep were adapted to forage rape over 32 days and then randomly allocated to one of two groups: diets supplemented with SC or not (control). Methane emissions were measured from intact sheep in seven experimental periods. In parallel, ruminal pH and fermentation characteristics were assessed using the fistulated sheep. In the first (P01) and the second (P02) periods, none of the sheep received SC to examine the baseline CH4 emissions. The P01 period was used as a covariate for analysis of gas emission measurements in subsequent measurement periods. Sodium carbonate was offered at 5% of the forage DM in P03 and P04, increased to 8% in P05 and P06 to assess the effect of pH increase on CH4 emissions and stopped in P07 to assess if the CH4 emissions reverted to values similar to those measured before the supplementation started. Methane yield (g/kg forage DM intake) was similar for the sheep in both groups during P02 and P03, but sheep supplemented with SC in the diet emitted 36%, 49% and 30% more CH4 per unit of forage DM intake than those in the control group during P04, P05 and P06, respectively. Emissions returned to similar levels when SC supplementation was ceased in P07. Ruminal pH was 0.412 to 0.565 units higher in SC supplemented sheep than for the control group during the SC treatment periods. Based on the lack of an immediate response in CH4 emissions to the supplementation of SC in P03, the positive responses in P04 to P06 and the rapid disappearance of the response after supplementation with SC stopped in P07, we propose a new hypothesis that ruminal pH effects on CH4 emissions are possibly through medium-term changes in microbial and methanogenic communities in the rumen, rather than a direct, short-term impact on methanogens per se. In conclusion, SC supplemented to the forage rape diet of sheep increased rumen pH, leading to an increase in CH4 emissions. Low ruminal pH in sheep fed forage rape explains, at least partially, the reported low CH4 emissions from sheep fed with this forage crop.

Acid soils often have low P availability limiting plant growth, which is addressed by application of inorganic fertilizers and neutralizing agents. However, little is known about the effect of addition of inorganic P and neutralizing agents on P pools in acid sulfate soils under submerged or moist conditions. Sulfuric acid sulfate soil (pH

It has previously been suggested that a local pH increase at pore surfaces is responsible for desorption of polar oil components and wettability alteration in sandstone reservoirs, leading to incre...

In this study, the performance of volatile fatty acids (VFAs) production and phosphorus (P) release during Al-waste activated sludge (Al-WAS) anaerobic fermentation with stepwise pH increases from 8 to 11 was investigated via a long-term acclimation strategy. As results, VFAs concentration increased with increasing pH and the maximum yield of VFAs was 358.03 mg-COD/g VS at pH 11, which was much higher than at pH 8. P was also released during the process, and the P concentration increased gradually from 26 mg/L at pH 8 to 186 mg/L at pH 11, accounting for 35.8% of the total P in the Al-WAS. The P distribution results demonstrated the dissolution of non-apatite inorganic phosphorus (NAIP) and organic P in the sludge contributed to release P into the liquid at pH 8, 9, and 10, while inorganic P release originated from the dissolution of NAIP at pH 11.

Collagen mimetic peptides (CMPs) based on repeating triads of [Gly-Pro-Pro] are guided by an N-terminally located SWCGTTPGSWCGT domain (cysteine rich wc2-knot foldon) to form collagen triple helix (CTH) motifs. The implementation of depsi “switch” defects into the peptide sequence SWCGTTPGSWCGT-[GPP]7 (wc2-[GPP]7) is disturbing the CTH formation at pH ≤ 5.5. Whereas upon pH increase to pH = 7.4 a rapid O → N-acyl transfer rearrangement takes place. This reinstalls the native amide backbone structure and contributes to the acceleration of the CTH formation. A set of wc2-[GPP]7 constructs is synthesized and “switch” defect segments are positioned either C-terminal, or N-terminal and at both termini. Circular dichroism (CD) spectroscopy in combination with CTH melting studies allows to investigate the effect of defect positioning on wc2-foldon organization, [GPP]7 triple helix motif formation and the respective thermal stability of the resulting CTH structures. C-terminal defects improve the anticipated zipper-like process of the wc2-guided CTH formation, whereas N-terminal defects are more disturbing the structure formation by interfering with the wc2-domain organization.

This paper investigates the effect of TT- LYK as an inhibitor on the copper chemical mechanical planarization with Ru/Ta as barrier layer. The results show that the TT-LYK can obviously reduce the dissolution rate of Cu. It can effectively passivate the copper surface. The results also show that the passivation capability was decreased as pH increase from 8 to 10. The effect of TT- LYK on dishing and erosion with different pattern density was also studied. However, the addition of TT-LYK is almost unchanged the removal rate of Ru. The rate of Ru is almost zero compared to the rate of copper. The passivation mechanism of TT-LYK on Cu CMP was revealed by electrochemistry.

The synthesis of a series of molecular actinyl(VI), namely, uranium(VI), neptunium(VI), and plutonium(VI), hydroxo-bridged dimers is reported. These complexes were isolated from an aqueous nitrate solution by titration with tetramethylammonium hydroxide. The solid-state structures were determined using single-crystal X-ray diffraction, revealing molecular complexes with the formula [Me4N]2[(AnO2)2(μ2-OH)2(NO3)4], where An = UVI, NpVI, and PuVI. Spectroscopic data-UV-vis-near-IR absorption, IR, and Raman-were collected on the solutions and solid-state complexes where available and compared to those of the aqueous solutions from which the crystals formed. These data provide structural evidence for higher-order polynuclear complexes of actinyl(VI) complexes upon a pH increase in the aqueous solution, confirming earlier thermodynamic models.

In this work, a novel combination of pyrite with zero valent iron (ZVI) was used to enhance the efficiency of Cr(VI) removal in column experiments, simulating the operation of permeable reactive barriers (PRBs).The influence of pyrite dosage, initial pH, and the mixing manner on the removal efficiency were evaluated. The synergetic effect between pyrite and ZVI was found to contribute to enhanced Cr(VI) removal in column experiments using the ZVI/pyrite mixture, by which the Cr(VI) removal could be kept at >90% for 50–100 PVs in comparison with ∼30 PVs by using ZVI alone.The Cr(VI) removal efficiency by the ZVI/pyrite mixture was also much higher than the sum of those by ZVI and pyrite separately in the batch experiments. Mechanism investigations indicated that the synergetic effect was principally attributed to the more reactive Fe2+ regenerated in the columns using the ZVI/pyrite mixture, due to reaction of pyrite with Fe3+ produced during Cr(VI) reduction. In addition, pyrite could suppress the pH increase and retard the surface passivation of active materials. The by-product SO42− from pyrite oxidation is also beneficial for enhanced removal efficiency. X-ray photoelectron spectroscopy (XPS) and Scanning electron microscopy-Energy dispersive spectrometry (SEM-EDS) studies confirmed the reduction of Cr(VI) into Cr(III), and that more pyrite was consumed in the Cr(VI) reduction by the ZVI/pyrite mixture. These findings are useful for developing cost-efficient methods for enhancing the removal of pollutants by ZVI-PRBs.

Freeze-thaw cycles impact the amount of aggregation observed in antibodies and Fc-fusion proteins. Various formulation strategies are used to mitigate the amount of aggregation that occurs upon putting a protein solution through a freeze-thaw cycle. Additionally, low pH solutions cause native antibodies to unfold, which are prone to aggregate upon pH neutralization. There is great interest in the mechanism that causes therapeutic proteins to aggregate since aggregate species can cause unwanted immunogenicity in patients. Herein, an increase in aggregation is reported when the pH is adjusted from pH 3 up to a pH ranging from pH 4 to pH 7 during the thaw process of a frozen antibody solution. Raising the pH during the thaw process caused a significant increase in the percent aggregation observed. Two antibodies and one Fc-fusion protein were evaluated during the pH jump thaw process and similar effects were observed. The results provide a new tool to study the kinetics of therapeutic protein aggregation upon pH increase. Keywords: Monoclonal antibodies, Freeze–thaw, Protein aggregation, Protein stability

Corrosion-induced CaCO3 scaling is extremely widespread at metal/water interface. However, the anti-scale and anti-corrosion behaviour of existing inhibitors have mostly been investigated separately without considering their interaction. Herein, the roles of corrosion inhibition in mitigating interfacial scaling were evaluated on carbon steel and stainless steel by introducing NaNO2 to enhance their corrosion resistance. Results reveal that corrosion-induced pH increase at micro cathodes dominates the interfacial scaling processes by inducing rapid nucleation. A temperature elevation promotes interfacial scaling mainly through aggravating steel corrosion. Once the micro cathodic processes are inhibited, CaCO3 scaling can be evidently retarded even at elevated temperatures.

High methoxylated citrus pectin was deesterified by alkaline or pectin methylesterase (PME) to produce pectin with various methoxylation degree (DM) from ~50% to 10. At pH 12 pectin DM could be reduced to lower limit of 15.91 ± 2.55% under 4 ℃ after 300 min but further to 6.81 ± 1.46% under 20 ℃ within 30 min. Stronger alkaline treatment led to heavier pectin degradation, especially suggested by the statistically significant (p 44 mg/g), but particularly the product with DM of 9.36% could gel at low Ca2+ concentration (4–8 mg/g). Enzymatic deesterified pectin produced by RAPIDASE® PEP (DM 30.83%) and ROHAPECT MPE (DM 14.67%) could gel at pH 2 in the absence of Ca2+ and their Ca2+-dependence increased with pH increase, while the product by NOVOSHAPE KEN00536 always needed > 24 mg/g Ca2+ for gelling under pH 2.0–4.0.

The diagnoses of bacterial infections remain a challenge in environment safety and human health area. Nanomaterial-based ‘enzyme nose’ sensor is a useful analytical technique for the detection of toxicologically important targets in biological samples. In this paper, we used three quaternized magnetic nanoparticles–urease sensors to detect bacteria with excellent sensitivity for several gram-positive or gram-negative bacteria. The response intensity of the nanoarray sensor is dependent on the level of displacement determined by three quaternized magnetic nanoparticles–urease binding strength and pathogenic cells–nanoparticles interaction. Based on the ability of urease to hydrolyze urea and increase the pH value of the system, the detection of pathogen is translated into a pH increase, which can be readily detected using a litmus dye. These characteristic responses of color show repeatable pathogenic cells and can be differentiated by principle component analysis (PCA). Our approach has been used to measure bacteria with an accuracy of 90.7% for 102 cfu mL−1 within 30 min. The measurement system has a potential for further applications and provides a facile and simple method for the rapid analysis of pathogens.

In this study, the dominant geological factor that influences the element distribution in sphalerite was determined and the behaviors of the elements under a single factor were investigated (e.g., temperature). To this end, two multivariate statistical analysis methods, namely, principal component analysis (PCA) and factor analysis (FA), were performed on a published sphalerite dataset containing 1336 analysis points from 52 deposits. The PCA produced five element clusters, which were each controlled by the five dominant factors identified by the FA (including magmatic-derived materials, temperature, pH, element remobilization, and dynamic recrystallization). Furthermore, the influence of temperature on the trace element composition of sphalerite was quantitatively expressed based on the corresponding homogenization temperature of fluid inclusions from 27 deposits, i.e., TFAS (°C) = (32.22 ± 1.88) × FAS + (245.49 ± 3.79) ( R a 2 = 0.918). The above research was then applied to the sphalerite from the Baoshan Cu-Pb-Zn deposit to reveal its metallogenic conditions. The results indicate that from the central-western mining districts to the northern mining districts, the contributions of the magmatic-derived materials, temperature, and fO2 decrease, whereas the contributions of the basement-derived hydrothermal fluid and pH increase.

Linear statistic N-isopropylacrylamide copolymer containing 11.6 mol% of 4-vinylpyridine was synthesized by free radical polymerization. The copolymer was investigated in 0.015 g cm−3 aqueous solutions using methods of static and dynamic light scattering and turbidimetry in the temperature region from 10 to 50 °C. Phase separation was registered in solutions in pH interval from 1.9 to 11.5 while heating. Temperatures of the onset and the termination of the phase separation decreased with pH increase in acid and neutral conditions. Intensive aggregation of macromolecules was registered starting from the temperatures of the onset of the phase separation. The aggregate size and their fraction in solution increased rapidly within the phase separation temperature interval; the composition of the dissolved species was strongly dependent on temperature as well as on pH.

Introduction Dissolution of the enamel in the form of erosion has increased due to shift in eating habits toward carbonated drinks like soft drink and chocolates. Aim The purpose of this study was to evaluate changes in the salivary pH after intake of different eatables and beverages in children at different time intervals. Study design Using standard salivary tests, this study was conducted as a case-control study. Fifty children between ages of 8 and 12 years having strict vegetarian diet were included in the study. Materials and methods Oral prophylaxis was done and salivary buffer capacity for stimulated saliva was measured. Before the saliva collection, each of the children was informed not to eat or drink anything for up to 2 hours just before the appointment. Results On pairwise evaluation, all the differences were found to be significant statistically except between baseline vs 30 minutes. Maximum mean difference was calculated and observed between baseline and immediately after intake of fruit juice and immediate after 30 minutes, 0.953 and 0.963 respectively, while minimum difference was calculated and observed between baseline and 30 minutes after intake of fruit juice (0.010). Conclusion Maximum drop was seen in cold drink when compared with fruit juice. The maximum pH increase was observed in cream biscuits with 7.63 ± 0.20. It was observed that in all the groups, the pH gradually got back to near normal levels due to the buffering mechanism of saliva.How to cite this article: Pachori A, Kambalimath H, Maran S, Niranjan B, Bhambhani G, Malhotra G. Evaluation of Changes in Salivary pH after Intake of Different Eatables and Beverages in Children at Different Time Intervals. Int J Clin Pediatr Dent 2018;11(3):177-182.

The pH meter, one of the most common sensors for laboratory measurements, has the advantages of excellent sensitivity, low price, high reliability, and ease of use. In this study, the high sensitivity of the pH meter was coupled with the high selectivity of immunosorbent assay to develop a simple and portable biosensor for aflatoxin B1 (AFB1) determination. Urease was first labelled on the AFB1 antigen, in the presence of AFB1; the target competed with the urease-labeled AFB1 antigen to be captured by the antibody. Urease could catalyse the hydrolysis of urea into ammonia and induce the pH increase of the solution; the change could easily be detected using a handheld pH meter or pH-sensitive dye. Under optimized conditions, the pH value enhancement had a linear relationship with the logarithm of the concentration of AFB1 in the range of 0.62 to 23.42 ng mL−1. The proposed biosensor has been applied to detect AFB1 in real samples with satisfactory results.

Background/Purpose: Particularly in pediatric patients, determining the cause of symptoms that arise with an infected wound can be tricky. I saw a gap in the biotechnology marketplace for a simple wound dressing that alerts patients when to seek medical attention for a possibly infected wound. In infected wounds, bacterial growth causes the breakdown of the extracellular matrix (ECM), producing basic byproducts. This rise in pH is reflected in the exudates produced by an infected wound and occurs immediately after contamination. Generally, the pH increase continues to rise until reaching a plateau, often after a few days of uncontrolled bacterial …

The apoplast is an interconnected compartment with a thin water-film that alkalinizes under stress. This systemic pH increase may be a secondary effect without functional implications, arising from ion movements or proton-pump regulations. On the other hand, there are increasing indications that it is part of a mechanism to withstand stress. Regardless of this controversy, alkalinization of the apoplast has received little attention. The apoplastic pH (pHapo) increases not only during plant–pathogen interactions but also in response to salinity or drought. Not much is known about the mechanisms that cause the leaf apoplast to alkalinize, nor whether, and if so, how functional impact is conveyed. Controversial explanations have been given, and the unusual complexity of pHapo regulation is considered as the primary reason behind this lack of knowledge. A gathering of scattered information revealed that changes in pHapo convey functionality by regulating stomatal aperture via the effects exerted on abscisic acid. Moreover, apoplastic alkalinization may regulate growth under stress, whereas this needs to be verified. In this review, a comprehensive survey about several physiological mechanisms that alkalize the apoplast under stress is given, and the suitability of apoplastic alkalinization as transducing element for the transmission of sensory information is discussed.

Careful handling of fish and shellfish onboard at the vessel is of prime importance in order to maintain the freshness. Use of slurry ice for onboard fish storage allows rapid heat transfer as well as reduces damage to the product by conventional ice. In the present investigation, the effect of onboard chilling with conventional ice and slurry ice on the quality of squid was evaluated. Samples stored at different time intervals (7th and 11th day) were collected and analyzed for their biochemical, textural and microbiological quality characteristics. Use of slurry ice, immediately after catch of squid reduced the formation of nitrogenous substances as well as the rate of pH increase during storage. Total volatile base nitrogen, tri methyl amine nitrogen and thio-barbituric acid values were within the acceptable limit in both the samples. Texture analysis showed higher hardness, springiness, gumminess and chewiness values for squid samples stored under slurry ice than the samples stored under conventional ice. Further, squid samples stored under slurry ice exhibited higher values of salt content. Microbiological analysis showed significant difference (p

A simple on package indicator label for grapes (Vitis vinifera L.) ripeness has been developed based on chlorophenol red (CPR). The CPR was immobilized onto the filter paper via absorption method to make the CPR membrane. The membrane as a colorimetric label for grape ripeness works based on pH increase as the volatile organic acids decreased gradually in the package headspace due to the formation of sugars during berry ripening process. Subsequently, the color of the indicator label will change from white to beige then finally to yellow for over-ripe indication, which is easily detected by naked eye. The results show that the indicator label could be used to monitor the ripeness of grapes since the color changes of indicator label toward the ripeness of the grapes are in similar tendency and have a good linear correlation. Thus, the indicator label can be used as an effective tool for on-line ripeness monitoring of grapes packaging. Finally, the indicator label was successfully used as on-package indicator label for on-line ripeness monitoring of grapes in ambient and chilled conditions.

White rot fungi have been extensively reported to have strong adsorption capacity to heavy metal ions, whereas the knowledge of extracellular polymeric substances (EPS) from the fungus has been rarely involved. In this study, the contribution characteristics of ‘the in situ EPS in Phanerochaete chrysosporium to Pb immobilization were investigated. First of all, the component and amount of EPS were investigated. It was found that the main component of EPS was carbohydrates, and highest EPS amount was produced at 5 days. In the Pb2+ immobilization experiments, EPS was demonstrated to play a more important role in immobilizing Pb2+ at lower initial Pb concentration. pH increase was beneficial for EPS to immobilize Pb. Higher EPS amount increased the Pb removal efficiency at a certain extent, while the specific uptake decreased. The Pb2+ immobilization by EPS produced at 7 days was most successful.

In bone implants, antibacterial biomaterials with nonleaching surfaces are superior to ones based on abrupt release because systemic side effects arising from the latter can be avoided. In this work, a nonleaching antibacterial concept is demonstrated by fabricating 2D nanoflakes in situ on magnesium (Mg). Different from the conventional antibacterial mechanisms that depend on Mg2+ release and pH increase, the nanoflakes exert mechanical tension onto the bacteria membranes to destroy microorganisms on contact and produce intracellular stress via physical interactions, which is also revealed by computational simulations. Moreover, the nanoflake layer decelerates the corrosion process resulting in mitigated Mg2+ release, weaker alkalinity in the vicinity, and less hydrogen evolution, in turn inducing less inflammatory reactions and ensuring the biocompatibility as confirmed by the in vivo study. In this way, bacteria are killed by a mechanical process causing very little side effects. This work provides information and insights pertaining to the design of multifunctional biomaterials., Nanoflakes are fabricated that stretch bacteria on contact with assistance of the zigzag structure on the edge. The mechanical stress imposed on bacteria triggers a series of reactions such as membrane rupture and reactive oxygen species burst leading to bacterial death. Biomaterials with the nonleaching antibacterial ability are very promising in implants and cause little side effects and inflammation in vivo.

The Al incorporation on SBA-15 type material and the effects of pH adjusting and presence of NaF were studied. The direct synthesis method was performed for comparison. The following parameters were evaluated: the Si/Al ratio, pH increase, and amount of NaF added. These parameters have a great influence on the synthesis of the mesoporous Al/SBA-15 type, but the pH the most influential parameter for the incorporation of Al into the SBA-15 structure. The formation of the SBA-15 structure was observed through the direct synthesis method. However, aluminum is not present in the material. The increase in pH contributed to the formation of a disorganized material. By EDX, it was observed that synthesis with a Si/Al = 5 ratio and pH approximately 4 provides materials containing aluminum. When the amount of aluminum during the synthesis is lower, a pH of approximately 8 is required to incorporate aluminum into the final material. The Al-NMR analysis showed that it was possible to insert aluminum in the structure of SBA-15, but with the presence of aluminum hexa and pentacoordinated. In the catalytic test of the dehydration reaction of ethanol, the samples with higher aluminum contents showed better catalytic performance due to its higher acidity.

The spotlighted dual functions of pyridine as a denaturant and as a stabilizer for duplex DNA are thoroughly investigated using spherical nucleic acids (SNAs). At neutral pH, pyridine destabilizes the duplex interconnects of assembled SNAs, resulting in a gradual decrease in their melting temperature (Tm) as a function of the pyridine concentration. This result is in good agreement with the conventional role of pyridine as a powerful denaturant for free duplex DNA. On the contrary, the addition of pyridine dramatically increases the Tm of hybridized SNAs under acidic conditions, which could be a striking result of pyridine’s stabilizing effect for DNA duplex as previously suggested on the basis of the pyridine–nucleobase interactions. After comprehensive and quantitative investigation based on the analysis of the sharp melting transitions of SNAs, however, we report that, in fact, the pH increase induced by pyridine is also an essential parameter accounting for pyridine’s DNA-stabilizing effects under aci...