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Regular application of phosphorus (P)-rich biosolids to limited land areas poses a potential eutrophication risk because of rapid soil P accumulation and increased transport of P in land runoff to receiving waterbodies. To assess the effect of biosolid-P on eutrophication risk, we tested the effect of a range of stabilized biosolids on soil test P ( STP) accumulation (measured by Olsen-P), and resulting increases in the potential release of soluble P to runoff (measured by soil water-extractable P ( WEP)), for five major UK soil types in a 90-day incubation study. Rates of Olsen-P increase (range 1-18% of total P applied) were greatest for lime-stabilized biosolids and least for Fe-rich and thermally dried biosolids. Increases in Olsen-P were not always accompanied by increases in WEP. Biosolids which contained large amounts of P-binding elements (e.g. Ca and Fe) actually reduced WEP concentrations on poorly buffered soils. There was less effect of biosolid type on highly buffered soils, which continued to release low amounts of soluble P even at high Olsen-P concentrations (up to 57 mg/kg). Soil WEP concentrations tended to increase more rapidly above ca. 20% soil P saturation, when the P sorption index was >6, and for biosolids with a molar Fe:P ratio of >1.2, but these potential thresholds require further verification under field conditions. Our results suggest the eutrophication risk associated with biosolids application can be overestimated, and they support the more widespread use of this valuable and renewable nutrient resource on some UK soils. [ABSTRACT FROM AUTHOR]

The suitability of electrokinetic remediation for removing heavy metals from dredged marine sediments with high acid buffering capacity was investigated. Laboratory-scale electrokinetic remediation experiments were carried out by applying two different voltage gradients to the sediment (0.5 and 0.8 V/cm) while circulating water or two different chelating agents at the electrode compartments. Tap water, 0.1 M citric acid and 0.1 M ethylenediaminetetraacetic acid (EDTA) solutions were used respectively. The investigated metals were Zn, Pb, V, Ni and Cu. In the unenhanced experiment, the acid front could not propagate due to the high acid buffering capacity of the sediments; the production of OH ions at the cathode resulted in a high-pH environment causing the precipitation of CaCO and metal hydroxides. The use of citric acid prevented the formation of precipitates, but solubilisation and mobilisation of metal species were not sufficiently achieved. Metal removal was relevant when EDTA was used as the conditioning agent, and the electric potential was raised up to 0.8 V/cm. EDTA led to the formation of negatively charged complexes with metals which migrated towards the anode compartment by electromigration. This result shows that metal removal from sediments with high acid buffering capacity may be achieved by enhancing the electrokinetic process by EDTA addition when the acidification of the medium is not economically and/or environmentally sustainable. [ABSTRACT FROM AUTHOR]

Aims and Objectives: The aim of this study is to compare surface pH in various parts of the oral cavity between patients with gastroesophageal reflux disease (GERD) and healthy controls. Methods: Using a flat pH meter sensor, fixed electrode pen type digital pH meter, oral pH levels were assessed at different mucosal sites among 34 GERD patients and 32 healthy controls. Salivary flow rates and buffering capacity were also assessed in them. A thorough oral examination was performed to screen for any oral and dental changes. Result: A significantly lower pH of 6.65 ± 0.13 (mean ± SD) was found in the GERD group compared to control group 7.23 ± 0.12 ( p < 0.05). Least pH was found in the floor of the mouth 6.594 ± 0.17 and highest in the lower labial mucosa among the GERD patients. Salivary flow rate and buffering capacity were low in these patients. Significant changes were noticed in the hard and soft tissues of the oral cavity among the GERD group. Conclusion: Oral mucosal pH is altered in GERD patients and may contribute to effects on the oral cavity. [ABSTRACT FROM AUTHOR]

Background: Reported vaginal and seminal fluid simulants have complex compositions with multiple preparatory steps that contribute to physical instability. We report the design and characterization of stable and simplified buffers that mimic the salient physical/chemical properties of the physiological fluids.Study Design/methods: Human cervicovaginal and seminal fluid samples were collected and buffering capacity was determined. The major buffering species were identified from published compositions of reproductive tract fluids. These values were used to compute the composition of vaginal and seminal fluid simulants. Ionic strength, buffering capacities, pH and osmolalities were then calculated or experimentally determined. Finally, cytotoxicity was evaluated in HEC-1-A cells and 3D reconstructed EpiVaginal™ tissue (VEC-100-FT) using naïve cells/tissue and nonoxynol-9 as controls.Results: The use of calculated amounts of conjugate acid and base for buffer development resulted in compositions that did not require endpoint pH adjustment and could be formulated as stable 10× concentrates. Furthermore, due to the absence of complex divalent salts, all our proposed simulants were stable at 4 °C for 1 month whereas precipitation and pH and osmolality changes were noted in reported buffers. Experimental determination of buffering capacities yielded similar values for undiluted cervicovaginal fluid (β4.2-5.2=35.6 ± 12.3 mM, N=7) and human seminal fluid (β7-6=37.5 ± 5 mM, N=3). All neat simulants showed significant cytotoxicity in HEC-1-A cells but were well tolerated by organotypic vaginal tissue.Conclusions: We report revised and improved compositions of buffers mimicking salient properties of vaginal and seminal fluid necessary for in vitro product evaluation.Implications: To support research in reproductive health and in particular drug delivery, we have designed and characterized stable new media to mimic these important fluids that can be used in a variety of in vitro studies. [ABSTRACT FROM AUTHOR]

The brains of some diving mammals can withstand periods of severe hypoxia without signs of deleterious effects. This may in part be due to an enhanced cerebral capacity for anaerobic energy production. Here, we have tested this hypothesis by comparing various parameters of the lactate dehydrogenase (LDH) in the brain of the hooded seal ( Cystophora cristata) with those in the brains of the ferret ( Mustela putorius furo) and mouse ( Mus musculus). We found that mRNA and protein expression of lactate dehydrogenase a (LDHA) and lactate dehydrogenase b (LDHB), and also the LDH activity were significantly higher in the ferret brain than in brains of the hooded seal and the mouse ( p < 0.0001). No conspicuous differences in the LDHA and LDHB sequences were observed. There was also no difference in the buffering capacities of the brains. Thus, an enhanced capacity for anaerobic energy production likely does not explain the higher hypoxia tolerance of the seal brain. However, the brain of the hooded seal had higher relative levels of LDHB isoenzymes (LDH1 and LDH2) compared to the non-diving mammals. Moreover, immunofluorescence studies showed more pronounced co-localization of LDHB and glial fibrillary acidic protein in the cortex of the hooded seal. Since LDHB isoenzymes primarily catalyze the conversion of lactate to pyruvate, this finding suggests that the contribution of astrocytes to the brain aerobic metabolism is higher in the hooded seal than in non-diving species. The cerebral tolerance of the hooded seal to hypoxia may therefore partly rely on different LDH isoenzymes distribution. [ABSTRACT FROM AUTHOR]

A novel amphoteric starch incorporating quaternary ammonium and phosphate groups was applied to investigate the efficiency and mechanism of cationic and anionic contaminant treatment. Its flocculation abilities for kaolin suspension and copper-containing wastewater were evaluated by turbidity reduction and copper removal efficiency, respectively. And the kinetics of formation, breakage and subsequent re-formation of aggregates were monitored using a Photometric Dispersion Analyzer (PDA) and characterized by flocculation index (FI). The results showed that amphoteric starch possessed the advantages of being lower-dosages-consuming and being stronger in shear resistance than cationic starch, and exhibited a good flocculation efficiency over a wide pH range from 3.0 to 11.0. [ABSTRACT FROM AUTHOR]

The effect of the buffering capacity of wort on a beer fermentation and the contribution of pH, phosphate, amino acids and organic acids to the buffering capacity of wort were studied. The beer pH depended on the buffering capacity of the corresponding wort and an increase in the buffering capacity of the wort could prolong the time of diacetyl conversion. The higher the wort pH was, the larger the wort buffering capacity. Phosphate was not an effective buffer at the pH of wort. Glutamic acid, aspartic acid and histidine gave weak contributions to the buffering capacity of wort, and the total contribution of these three amino acids was <0.1. Organic acids contributed substantially to the buffering capacity of the wort and the total contribution of organic acids to the buffering capacity of the wort was estimated to be about 0.31. The buffering capacity of lactic acid, citric acid, succinic acid, fumaric acid and pyruvic acid was 30, 50, 77, 15 and 9% of that of acetic acid, respectively, at the same mass concentration. Copyright © 2015 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Aim: This study the evaluated interactions of capsulated glass ionomer cements (GIC) with an aqueous lactic acid solution. Materials and Methods: GIC fuji cap II and GC fuji cap IX were tested and compared to vials containing a lactic acid aqueous solution with no specimen as the control group. 16 specimens of each material were made according to the manufacturer’s instructions. The pH of the solution was measured immediately after 24 hours and at the end of the week. The statistical significance in the pH of the storage solution was determined by using one–way ANOVA. Result: All the materials were able to increase the pH of the lactic acid solution and both the materials were statistically significant. Conclusion: These findings can be helpful in predicting the performance of these materials under clinical conditions.

Young pigs have an immature gut and do not provide adequate gastric acidity to digest nutrients and inhibit bacteria growth in the gut. Diets have intrinsic ability to alter gastric acidity. Acid-binding capacity (ABC) and buffering capacity (BC) are often used to describe the ability of feedstuffs to influence pH changes, but methods to measure and units to express ABC and BC values vary among studies and need standardisation. Some feed ingredients, noticeably minerals have high ABC values, thus could neutralise gastric acidity in pigs. The ABC values are related to initial pH but vary among and within feedstuffs, thus, more research is required to depict the full picture. Diets with high ABC values are detrimental to young pigs. Diet ABC values can be reduced by lowering protein content, alternative use of minerals, coarse grinding, and inclusion of organic acids (OA). Most OA have negative but varied ABC values and are effective and practical in lowering pH and ABC values of diets. However, their ability to alter gastric acidity has been inconsistent. Whether dietary OA inhibits hydrochloric acid secretion in the stomach of pigs requires elucidation. Lowering ABC values may increase ileal digestibility of protein and improve growth performance of pigs. However, the dose response of OA to lower ABC values of diets on growth performance of pigs is inconsistent. Other dietary factors, e.g., mineral and fibre content or the ABC value of the basal diet may affect efficacy of OA. Lowering diet ABC values via dietary OA and OA salts may increase microbiota diversity and reduce E. coli counts in the gut, reduce diarrhoea incidence and Salmonella prevalence, and reduce ammonia emission, thus has the potential to replace antibiotics and zinc oxide used in pig feed currently. However, lowering diet ABC values via certain dietary OA may affect feed palatability and preference, cause metabolic acidosis and affect bone health of pigs. In conclusion, diet composition determines its ABC value that affects diet nutrient digestion, growth performance and gut health of pigs. Incorporating the concept of lowering ABC values of feed is an important factor to manage growth performance and gut health of young pigs. To establish and verify a system of using ABC values to formulate pig diets, more research is warranted. • Feed has impact on gastric acidity, and subsequently nutrient digestion in pigs. • Acid-binding capacity varies among and within feedstuffs. • Minerals with high acid-binding capacity neutralise gastric acidity and compromise nutrient digestion. • Dietary organic acids are effective in lowering acid-binding capacity of feed. • Lowering acid-binding capacity of feed benefits growth and gut health of pigs. [ABSTRACT FROM AUTHOR]

Acid rain is a global environmental problem that mobilizes heavy metals in soils, while the distribution and geochemical fraction of heavy metals during acid rain infiltration in heterogeneous soils are still unclear. In this study, we performed column experiments to investigate the distribution and geochemical fraction of Cu, Pb, Ni and Cd in heterogeneously layered soils during continuous acid rain infiltration. Chloride ion used as a conservative tracer was found to be uniformly distributed during acid rain infiltration, showing insignificant preferential flow effects in the column. In contrast, however, the distribution of heavy metals was highly non-uniform, especially in the silty soil at the lower part of the column, indicating a heterogeneous distribution of adsorption capacity. In addition, in the control experiments with neutral rain infiltration, uniform distribution of heavy metals was observed, indicating that the heterogeneous distribution of adsorption coefficient during acid rain infiltration was mainly caused by different pH buffering capacities. A numerical model considering water flow and solute transport was developed, where the average water-solid distribution coefficient (K d) in Layer 2 was only 1.5–12.5% of that in Layer 1 during acid rain infiltration. The model could predict the variation of heavy metal concentrations in soil with the majority of error less than 35%, confirming that different K d induced the heterogeneous distribution of heavy metals. In addition, the geochemical fraction of heavy metals in the upper coarse sand layer remained stable, while the acid-extractable fractions in the lower loam and silt loam layer gradually increased. Our findings suggest that soil heterogeneity, especially chemical heterogeneity affected by rainfall acidity, has an important influence on the infiltration, migration and geochemical fraction of heavy metals in soils. This study could help guide the risk assessment of heavy metal-contaminated sites that were polluted by acid rain or landfill leachate. • The effect of acid rain infiltration was investigated by experiments and modeling. • Soil adsorption capacity was non-uniformly distributed in acid rain infiltration. • Different pH buffering capacities caused non-uniform distribution of heavy metals. • The acid-extractable fractions in silty layer increased in acid rain infiltration. [ABSTRACT FROM AUTHOR]

In this work the effect of age and location within the stem on pH and buffering capacity of radiata pine sapwood was investigated. Mature and juvenile wood samples from three different heights in the trunk were obtained from 20, 25, and 30 year-old trees. Aqueous wood extracts from the samples were used to determine the pH and buffering capacity of wood. Results show a significant effect of age and location in the tree, although a strong interaction among all factors was also detected. In general sapwood tended to be more acidic in the lower part of trees, but juvenile wood showed to be more acidic than mature wood. From both type of wood tested, juvenile wood was more sensitive to change its pH and buffering capacity with the height and age. The effect of wood pH and buffering capacity in the manufacture of wood composites is discussed and further research is recommended to determine whether the variations detected in this study can affect the curing of resins and quality of wood base composite manufactured with radiata pine wood.

A field experiment was carried out to determine the effects of wood ash and refuse tea with urea on yield and nutrient status of tea. Experimental plots were located in the St Coombs Estate, Tea Research Institute, Talawakelle, Sri Lanka. Six treatments (1 ton wood ash plus 20 ton refuse tea ha -1 year -1 {T 1 }, 2 ton wood ash plus 20 ton refuse tea ha -1 year -1 {T 2 }, 1 ton wood ash plus 20 ton refuse tea plus 587 kg urea ha -1 year -1 {T 3 }, 2 ton wood ash plus 20 ton refuse tea plus 587 kg urea ha -1 year -1 {T 3 }, present TRI fertilizer mixture{T 3 }, and control{T 3 }, without any fertilization) were arranged according to Randomized Complete Block Design with three replicates. Macro and micro nutrient contents in soil and leaf were analyzed5 months after applying treatments and yield was recorded in weekly intervals.T 2 applied plots indicated significant positive effect (p<0.05) on the yield and significantly (p<0.05) higher Potassium and Calcium content in the soil. Significant effect (p<0.05) of Nitrogen and Carbon content in the soil was given by T 1 . Electrical conductivity and pH changes in soil were not any significantly different among all the treatments whilst higher macro and micro-nutrient concentration was observed in the soil, treated with T 1 ,T 2 ,T 3 and T 4 . It is evident from results that wood ash, refuse tea with urea can be successfully used to promote sustainable tea cultivation in the Mattakelle soil series (Rhodudults/Tropudults;USDA classification) which having high buffering capacity. [ABSTRACT FROM AUTHOR]

Postmortem lactate accumulation in skeletal muscle is linearly associated with the extent of pH decline. Yet, pigs harboring the AMPKγ3 R200Q mutation produce meat with similar lactate levels to that of wild-type pigs but have a lower ultimate pH. We hypothesized that lower initial lactate levels and (or) lower buffering capacity in muscle of these pigs may help explain this discrepancy. Longissimus lumborum muscle samples were harvested at 0 and 1440 min postmortem from AMPKγ3 R200Q and wild-type pigs. As expected, AMPKγ3 R200Q muscle exhibited a lower ultimate pH but similar lactate levels to that of wild-type pigs at 1440 min postmortem. However, the total net lactate produced postmortem was greater in the AMPKγ3 R200Q muscle due to lower initial lactate levels at 0 min postmortem. Buffering capacity measured over the pH range of 5.5–7.0 was also lower in AMPKγ3 R200Q muscle. Greater net lactate accumulation postmortem (i.e., glycolytic flux) coupled with a lower buffering capacity explains the lower ultimate pH of meat from AMPKγ3 R200Q pigs. [ABSTRACT FROM AUTHOR]

The termination of discontinuous gas exchange cycles (DGCs) in severely dehydrated insects casts doubt on the generality of the hygric hypothesis, which posits that DGCs evolved as a water conservation mechanism. We followed DGC characteristics in the two density-dependent phases of the desert locust Schistocerca gregaria throughout exposure to an experimental treatment of combined dehydration and starvation stress, and subsequent rehydration. We hypothesized that, under stressful conditions, the more stressresistant gregarious locusts would maintain DGCs longer than solitary locusts. However, we found no phase-specific variations in body water content, water loss rates (total and respiratory) or timing of stress-induced abolishment of DGCs. Likewise, locusts of both phases re-employed DGCs after ingesting comparable volumes of water when rehydrated. Despite comparable water management performances, the effect of exposure to stressful experimental conditions on DGC characteristics varied significantly between gregarious and solitary locusts. Interburst duration, which is affected by the ability to buffer CO2, was significantly reduced in dehydrated solitary locusts compared with gregarious locusts. Moreover, despite similar rehydration levels, only gregarious locusts recovered their initial CO2 accumulation capacity, indicating that cycle characteristics are affected by factors other than haemolymph volume. Haemolymph protein measurements and calculated respiratory exchange ratios suggest that catabolism of haemolymph proteins may contribute to a reduced haemolymph buffering capacity, and thus a compromised ability for CO2 accumulation, in solitary locusts. Nevertheless, DGC was lost at similar hydration states in the two phases, suggesting that DGCs are terminated as a result of inadequate oxygen supply to the tissues. [ABSTRACT FROM AUTHOR]

The study was carried out to assess forms of potassium (K) and K quantity–intensity relationships in six wetland soils in Abeokuta, Southwest Nigeria. Collected soil samples from pedogenic horizons of six profile pits were analyzed using appropriate techniques. The soils were loamy sand – sandy clay with very low to moderate (0.04–2.55%) organic carbon, low–medium (4.29–22.29 cmol kg−1) effective cation exchange capacity, high base saturation (89.42–99.56%), and low available phosphorus (≤1.90 mg kg−1). Values of exchangeable-K (0.05–0.20 cmol kg−1), mobile-K (0.26–1.53 cmol kg−1), reserved-K (0.51–2.56 cmol kg−1), residual-K (0.42–2.21 cmol kg−1), and total-K (1.02–3.32 cmol kg−1) were low. The buffering capacity of the soils for K (88.10–273.2 cmol kg−1(mol.L−1)½) and labile-K at specific site (4.48–16.43 cmol kg−1) were moderate and the free energy of replacement (5512.17–8414.94 J mol−1) was low. The results suggest that the soils have low capacity to fix K and could, therefore, release applied K fertilizer appropriately for crop uptake. The low-K status of the soil can be corrected by application of K fertilizers. [ABSTRACT FROM PUBLISHER]

Purpose: The aim of this study was to investigate how the disproportionation process can be impacted by the properties of the salt, specifically pH. Methods: Five miconazole salts and four sertraline salts were selected for this study. The extent of conversion was quantified using Raman spectroscopy. A mathematical model was utilized to estimate the theoretical amount of conversion. Results: A trend was observed that for a given series of salts of a particular basic compound (both sertraline and miconazole are bases), the extent of disproportionation increases as pH decreases. Miconazole phosphate monohydrate and sertraline mesylate, although exhibiting significantly different pH values (more than 2 units apart), underwent a similar extent of disproportionation, which may be attributed to the lower buffering capacity of sertraline salts. Conclusion: This work shows that the disproportionation tendency can be influenced by pH and buffering capacity and thus highlights the importance of selecting the appropriate salt form during the screening process in order to avoid salt-to-free form conversion. [ABSTRACT FROM AUTHOR]

The knowledge on the response of tidal-operated constructed wetlands (CWs) to suddenly changed influent characteristics, such as ammonium and organic matter concentrations, remains unclear. This study set up a pilot-scale tidal-operated CW and examined its response to various sudden organic matter and ammonium loading changes under constant hydraulic loading rate and retention time. Results showed an oxidative condition in the wetland bed with a high oxygen transfer rate induced by tidal operation. Effluent ammonium fluctuated from 0.5 mg/L to 62 mg/L when the ammonium pulse loadings were adopted, indicating the limited buffering capacity of tidal-operated CWs to influent ammonium pulse loadings because of the short contact time. No negative influence from influent COD pulse loadings to nitrification was observed, even when the influent COD concentration increased up to 1200 mg/L. The average constant effluent COD concentrations of 47 mg/L and high removal efficiencies of 93% under various pulse loadings (300–1200 mg/L) strongly indicated the high buffering capacity of tidal-operated CWs to suddenly changed organic matter loadings as well as its high degradation capacity driven by the enhanced oxygen transfer rate of tidal operation. [ABSTRACT FROM AUTHOR]

Background/purpose We explored changes in salivary gland function of head-and-neck cancer patients after radiotherapy, including pH of saliva, stimulated salivary flow rate, and saliva buffering capacity. The pH of saliva included that of parotid gland, submaxillary gland, and total resting saliva. We also investigated whether the acidity of dental plaque lowered pH of saliva. Materials and methods From a total of 62 patients, 11 had repeated measurements taken before and every month after radiotherapy. The remaining 51 patients had a single measurement taken after radiotherapy. Seven normal patients served as the control group. Results In the repeated measurement group, all examinations decreased dramatically in the 1 st month after radiotherapy (P < 0.0001), and recovered from the 3 rd month to the 6 th month, but the flow rate could not return to pretreatment level. In the single measurement group, unilabiate linear regression analysis showed that the time-period after radiotherapy was a significant predictor influencing the pH of the submaxillary gland and total resting saliva. Pearson correlation coefficient analysis showed that the pH of dental plaque had a positive linear correlation with that of saliva. Concerning the influence of time-period, within 1 year after radiotherapy, all examinations were dropped. After 1 year the pH of resting saliva and plaque began to increase over time. The stimulated flow rate, pH of stimulated saliva, and buffering capacity, dropped < 1 year after radiotherapy group, increased 1–5 years after radiotherapy group, but dropped again > 5 years after radiotherapy group. Conclusion Our results indicated that oral hygiene care is important especially during the early period after radiotherapy. [ABSTRACT FROM AUTHOR]

Understanding the possible pH-buffering processes is of maximum importance for risk assessment and remediation feasibility studies of heavy-metal contaminated soils. This paper presents the results about the effect of the buffering capacity of a polluted soil, rich in carbonates, on the pH and on the leaching evolution of its main contaminant (lead) when a weak acid (acetic acid) or a strong one (nitric acid) are slowly added. In both cases, the behavior of lead dissolution could be predicted using available (scientifically verified freeware) models assuming equilibrium between the solid and the aqueous phase. However, the experimental results indicate that the dissolution of calcium and magnesium carbonates is kinetically controlled. These kinetic limitations affect the overall behavior, and should be considered to understand also the response of the metals under local equilibrium. The well-known BCR sequential extraction procedure was used before- and after-treatment, to fractionate the lead concentration in the soil according to its mobility. The BCR results were also in agreement with the predictions of the equilibrium model. This agreement allows new insights about the information that could be derived from the BCR fractionation analysis. [ABSTRACT FROM AUTHOR]

The effects of three types of dietary sulfur on in vitro fermentation characteristics, sulfide production, methane production, and microbial populations at two different buffer capacities were examined using in vitro rumen cultures. Addition of dry distilled grain with soluble (DDGS) generally decreased total gas production, degradation of dry matter and neutral detergent fiber, and concentration of total volatile fatty acids, while increasing ammonia concentration. High buffering capacity alleviated these adverse effects on fermentation. Increased sulfur content resulted in decreased methane emission, but total Archaea population was not changed significantly. The population of sulfate reducing bacteria was increased in a sulfur type-dependent manner. These results suggest that types of dietary sulfur and buffering capacity can affect rumen fermentation and sulfide production. Diet buffering capacity, and probably alkalinity, may be increased to alleviate some of the adverse effects associated with feeding DDGS at high levels. [ABSTRACT FROM AUTHOR]

Fermentation experiments were designed to elucidate the functional role of the redox microenvironment on volatile fatty acid (VFA, short chain carboxylic acid) production and co-generation of biohydrogen (H 2 ). Higher VFA productivity was observed at pH 10 operation (6.3 g/l) followed by pH 9, pH 6, pH 5, pH 7, pH 8 and pH 11 (3.5 g/l). High degree of acidification, good system buffering capacity along with co-generation of higher H 2 production from food waste was also noticed at alkaline condition. Experiments illustrated the role of initial pH on carboxylic acids synthesis. Alkaline redox conditions assist solubilization of carbohydrates, protein and fats and also suppress the growth of methanogens. Among the carboxylic acids, acetate fraction was higher at alkaline condition than corresponding neutral or acidic operations. Integrated process of VFA production from waste with co-generation of H 2 can be considered as a green and sustainable platform for value-addition. [ABSTRACT FROM AUTHOR]

Flat band slow light is achieved in a silicon photonic crystal waveguide with large normalised delay bandwidth product (NDBP) while maintaining smaller values of group velocity dispersion. By altering the waveguide width through shifting the position of two rows of air holes adjacent to the waveguide, it is possible to achieve a high NDBP value. The NDBP values of 0.40, 0.41 and 0.43 over bandwidths of 11, 14 and 18 nm are, respectively, reported. Towards the applicability of the proposed slow light waveguide for buffering applications on silicon, buffering capacity as high as 140 bits can be achieved with the proposed design approach.z [ABSTRACT FROM AUTHOR]

[Display omitted] • Arctic soil pH buffering capacity (β) varies with depth and microtopography. • Soil water retention is an important proxy for β in organic-rich Arctic soils. • Variations in β modulate pH-sensitive biogeochemical transformations. • Earth system models neglecting β may yield CO 2 and CH 4 prediction uncertainty. Dynamic pH change promoted by biogeochemical reactions in Arctic tundra soils can be a major control on the production and release of CO 2 and CH 4 , which contribute to rising global temperatures. Large quantities of soil organic matter (SOM) in these soils are susceptible to microbial decomposition, leading to pH changes during permafrost thaw. Soil pH buffering capacity (β) modulates the extent of pH change but has not been thoroughly studied and represented in predictive ecosystem scale biogeochemical models in Arctic tundra soils. In this study, we generated titration curves for 21 acidic tundra soils from three Arctic sites across northern Alaska, United States of America. Geochemical and hydrological soil properties were evaluated, and correlations with β were developed. Strong correlations between β and both gravimetric water content (Θ g) (R2 = 0.847, p < 0.001) and soil water retention (SWR) (R2 = 0.849, p = 0.001) indicate that the ability of soil to retain water could be associated with its buffering properties. Correlations between β and soil organic carbon (SOC) and cation exchange capacity (CEC) were also explored, and relationships to SWR are discussed. These correlations were then used with existing soil databases reporting SOC, CEC, and SWR to estimate β across Alaska soils. We further demonstrated the quantitative relationships between β and the simulated rates of biogeochemical reactions and show that lower β leads to higher soil pH and more CH 4 production. Our study provides simple proxies for β in Arctic soils and highlights the importance and implications of representing soil buffering in predictive models, thereby enabling quantitative coupling between pH dynamics associated with biogeochemical reactions. Integrating β into predictive models of Arctic biogeochemical cycling may reduce model uncertainty and further our understanding of permafrost SOM degradation accelerated by warming. [ABSTRACT FROM AUTHOR]

Background: Although glass-ionomer cement (GIC) has many unique properties and advantages, it still lacks favorable mechanical properties. Cention N is a recent alkasite material with excellent mechanical properties. The purpose of this study was to compare the mechanical properties (fracture toughness [FT] and flexural strength [FS]) and acid buffer capability of an alkasite material to GIC. Materials and Methods: In this in vitro study, a total of 60 samples were prepared using Cention N or GIC. Twenty specimens (n = 10) were prepared using beam-shaped Teflon molds for FS, and twenty specimens (n = 10) were prepared with a similar mold with a notch for FT. These were evaluated on a universal testing machine using a three-point bend test. Twenty (n = 10) disk-shaped specimens were prepared for acid buffer capability. The samples were stored in distilled water for a week. This was followed by immersion in lactic acid with a pH of 4 for calculation of the materials acid buffering capacity at 30 and 60 min from exposure using a pH meter. The data obtained were tabulated and subjected to Kolmogorov–Smirnov test and Shapiro–Wilk test to assess the normal distribution and further analyzed using the Student's t-test to assess the level of significance, P < 0.05 was considered statistically significant. Results: The mean FT, FS, and acid buffer capability of Cention N were significantly higher than GIC at P < 0.05. Conclusion: The present study surmised that Cention N exhibited higher FT, FS, and acid buffer capability than GIC. [ABSTRACT FROM AUTHOR]

The production of volatile fatty acids (VFAs) and biohydrogen (bio-H 2) from food waste (FW) by acidogenic process is one of the promising strategies. The present study was performed to evaluate the role of initial (phase I) and intermittent pH (phase II) control strategies utilising combination of sodium hydroxide (NaOH) and sodium carbonate (Na 2 CO 3) as buffering/neutralizing agents on VFAs and bio-H 2 production from FW. The study was carried out in two bioreactor configurations (biofilm (UAFBB) and a suspended mode bioreactor (UASB)). Intermittent pH adjustment (phase II) increased hydrolysis and FW acidification compared to the initially adjusted pH (phase I), but had a detrimental influence on bio-H 2 generation in both the studied bioreactor configurations. Combining NaOH and Na 2 CO 3 resulted in higher buffering capacity and VFA production. The studied parameters in UAFBB aided in higher VFA (14.05 g/L; 48 h of cycle operation) and bio-H 2 (56%; 12 h of cycle operation) production during phase II and phase I operation, respectively. Overall, the results showed a synergy between the examined parameters, resulting in increased VFA production from FW. [Display omitted] • Fixed bed bioreactor showed effective acidogenesis. • Intermittent pH adjustment facilitated enhanced VFA production. • Inoculum pretreatment and alkaline pH operation suppressed methane production. • Na 2 CO 3 and NaOH showed positive impact on VFA production and system buffering. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermophilic anaerobic co-digestion with lipids and FW was evaluated. • Methanation was achieved at lipid/TS ratio up to 70%. • Degradation efficiency of lipids was about 90 % with different lipid/TS ratios. • TAN and Alk-6.5 were suggested as key monitoring indicators. A thermophilic anaerobic co-digestion system treating lipids and food waste was demonstrated by a long-term operation (over 600 days) with different lipid/TS ratios (from 10 % to 80 %). The lipids degradation efficiency achieved 90 % in the system when the lipid/TS ratio was less than 70 %. Addition of lipids significantly enhanced methane production, as the lipid/TS ratio increased from 10% to 70 %, the biogas production rate increased from 2.36 g/L/d to 3.42 g/L/d with 59.7 % to 67.7 % of methane. From the view of system stability, the increase of lipid/TS ratio reduced the alkalinity of the system and eventually caused the system collapse. In order to avoid losses due to overload, the results suggested that the ratio of total ammonia nitrogen to alklinity-6.5 could be used as a monitoring indicator. And the system could maintain efficient operation when the indicator was less than 0.6. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate the prediction of aerobic and anaerobic capacity from lactate relative change during isocapnic buffering phase in elite athletes. Methods: eight endurance and six sprint elite cyclists participated in the present study and performed one standard incremental test and a supramaximal exercise test on a cycle ergometer until exhaustion in 2 separate sessions. During the incremental test Breath-by-breath measurement of respiratory gas was performed and during the last 30 seconds of each 3-minute stage, blood samples were collected for lactate measurement. Lactate threshold (LT) and respiratory compensatory threshold (RCT) were defined as abrupt increase in blood lactate concentration in lactate - workload and abrupt increase in CO2 respiratory equivalent. Isocapnic buffering phase was defined as the time between LT and RCT. Two independent sample t-test was used for all comparison between groups and the relationship between variables was measured by Person correlation test. Results: lactate relative changes during isocapnic buffering phase in anaerobic cyclists were significantly higher than endurance group (p

A commercial plant extract (prepared from olive, garlic, onion and citrus extracts with sodium acetate ( SA) as a carrier) was evaluated to extend the viability of yogurt starter and probiotic bacteria as a means to enhance the shelf life of live and active culture, probiotic nonfat yogurt. Yogurts prepared from three different formulas (0.5% plant extract, 0.25% SA, or no supplement) and cultures (yogurt starter plus Bifidobacterium animalis, Lactobacillus acidophilus, or both probiotics) were assessed weekly during 29 days of storage at 5°C. Supplemented yogurt mixes had greater buffering capacities than non-supplemented yogurt mixes. At the end of storage, Lactobacillus bulgaricus and L. acidophilus counts in supplemented yogurts were greater compared with non-supplemented yogurts. Supplementation did not affect Streptococcus thermophilus and B. animalis counts. Hence the greater buffering capacity of yogurt containing plant extract could enhance the longevity of the probiotics, L. bulgaricus and L. acidophilus, during storage. [ABSTRACT FROM AUTHOR]

Chicken skin and chicken meat display different buffering effects which may impact the survival of Salmonella attached to them when treated with acids. This study investigated the role that differences in fat composition of chicken skin and meat play in their buffering capacity. The survival of Salmonella attached to chicken skin and meat in the presence of fat, and treated with acetic acid was also investigated. Fat was extracted from chicken skin and meat and the buffering capacities of chicken skin, meat, extracted fat and their respective remnants were determined. Two strains of Salmonella Typhimurium and two strains of S . Enteritidis were attached independently to each of the chicken component listed above and enumerated before and after treatment with 0.3 M acetic acid. Chicken skin has a higher fat content as compared to chicken meat. Skin (13 mmol H + /(pH∗ kg)) had a stronger buffering capacity (p < 0.05) than the extracted fat alone and skin remnants alone (7.0 mmol H + /(pH ∗ kg) and 6.9 mmol H + /(pH ∗ kg) respectively). From an initial inoculum (~ 9 log CFU/g), Salmonella cells attached better (p < 0.05) to chicken meat (~ 8 log CFU/g) and chicken skin (~ 7 log CFU/g) than extracted fat (~ 1.5 log CFU/g). Skin remnants without fat were better (p < 0.05) at protecting attached Salmonella than other chicken components. For example S . Typhimurium ATCC 33062 decreased ~ 1 log CFU/g (p < 0.05) on skin remnants after acetic acid treatment while its viable counts on other components decreased from ~ 1.5 to 7 log CFU/g (p < 0.05). We suggest that the fat content present in the skin may enhance the vulnerability of attached cells to acetic acid. [ABSTRACT FROM AUTHOR]

Background: Dental caries is a microbial disease characterized by demineralization of the inorganic portion and destruction of the organic substance of the tooth. Dental caries, its resulting discomfort and pain can interfere with their nutritional intake including iron which results in iron deficiency anaemia. Aims & Objective: To evaluate the association between iron deficiency anaemia with salivary pH and buffering capacity before and after iron supplementation in children of 6-12 years of age group. Materials and Methods: Dental caries was recorded as per World Health Organization criteria. Blood was drawn from the patients for the estimation of Hb, MCV, MCH and serum ferritin levels to diagnose the iron deficiency anaemia. Unstimulated Saliva was assessed for, salivary pH and buffering capacity. Blood as well as salivary parameters were measured in two occasions, before beginning of the treatment for iron deficiency anaemia and after completion of treatment of iron deficiency anaemia. The obtained data was tabulated and statistical analysis was done. Results: On statistical evaluation by students paired 't' test, the parameter like Hb, MCV, MCH, Serum ferritin, salivary pH, and buffering capacity after the iron therapy showed statistical significance, (p<0.001). It was also found that the correlation and association of iron deficiency anaemia was evaluated with the Hb, MCV, and salivary pH. Conclusion: Iron deficiency anaemia, the most commonly recognized form of nutritional deficiency, is prevalent among infants and young children as hypochromic microcytic anaemia. Due to change in the salivary pH and buffering capacity the risk of developing dental caries as well as deterioration of oral health is evident. Hence evaluation of these factors in saliva that may increase the risk of individuals to dental caries, can pave way to make recommendations that will cater specifically to needs of an individual. Iron therapy in iron deficiency anaemia can increase the levels of Hb, MCV, MCH, Serum ferritin, salivary pH and buffering capacity. Long term effect of iron deficiency anaemia on oral health is still needed to be explored. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate whether ground reed canary grass ( Phalaris arundinacea ) straw (RC) could be used to replace peat for short production cycle greenhouse crops. Characteristics of RC, peat, mixture of RC + peat (50% + 50%), and coir were determined and the performance of strawberry ( Fragaria × ananassa cv. Elsanta) on these substrates was evaluated. Water holding capacity of RC was low in comparison to peat and coir, but could probably be improved by decreasing its particle size in processing. The buffering capacity of RC was similar to coir, but clearly lower than in peat. Because of similar reactions to addition of base, liming recommendation of RC would probably be approximately the same as for peat. The C-to-N ratio was 60 in coir, 41 in peat, 23 in RC, and 29 in the mixture of RC + peat. High concentration of inorganic N in RC was rapidly consumed by the microbial activity in the incubation experiment. Vegetative growth of the strawberry plants was the most vigorous in peat, but the total yield, berry size, and sugar to acid ratio in berries were similar in all the substrates. In conclusion, ground reed canary grass may be used to replace peat or coir in soilless culture of strawberry. However, due to its low water holding capacity, irrigation regime has to be adjusted accordingly. [ABSTRACT FROM AUTHOR]

Gasification biochar represents one of the bio-char types tested for agricultural needs. The aim of this study was to clarify the physico-chemical and biological changes occurring in a peat-sand substrate amended with hardwood-derived gasifica-tion biochar in the rates of 2, 4 and 20 g l-1. The pH(H2O) of the substrate with 4 g l-1 and 20 g l-1 biochar was increased from 5.6 to 6.2 and 6.7, respectively. The testing of the substrate in the re-spirometry device showed that the increase in the biochar rate led to a decrease in the amount of CO2O evolved at the maximum pres-sure drop. The continuous decrease in pressure observed in the respirometry bottles filled with pure biochar allows explaining this effect by biochar sorption activity. Addition of 2 and 4 g l-1 biochar to the peat-sand substrate stimulated the growth of cucum-bers in an 18-day pot vegetation experiment. An increase in the number of root tips and root volume with a decreasing average root diameter was shown in the presence of biochar. Stimulation of plant growth on the background of low rates of biochar requires a further study with emphasis on the specific combination of bio-char, soil type, plant species, and climatic conditions. [ABSTRACT FROM AUTHOR]

The present work studied the solubilization of Ca during acidification in milk concentrated by ultrafiltration (UF) and diafiltration (DF). The effect of heating milk at 80°C for 15 min was also evaluated. In addition to measuring buffering capacity, the amount of Ca released as a function of pH was determined. The area of the maximum peak in buffering capacity observed at pH ~5.1, related to the presence of colloidal Ca phosphate, was significantly affected by casein volume fraction but did not increase proportionally with casein concentration. In addition, a lower buffering capacity and less solubilized Ca were measured in 2x DF milk compared with 2x UF milk. Heat treatment did not change the buffering capacity or Ca release in 1x and 2x concentrated milk. On the other hand, at a higher volume fraction (4x), more Ca was present in the soluble phase in heated 4x UF and DF milk compared with unheated milk. This is the first comprehensive study on the effect of concentration, distinguishing the effect of UF from that of DF, before and after heating, on Ca solubilization. [ABSTRACT FROM AUTHOR]

A study was conducted to investigate the effects of different additives on the fermentation quality of ensiled cassava leaves and its effects on the ruminal fluid parameters using eighteen West African dwarf goats. Cassava leaves were ensiled alone (ECF), with 5 % (w/w) molasses (ECFM) and caged layer waste (ECFP) respectively as additives for 30 days. Results of chemical composition of the additive and non-additive silages indicated that ensiling with 5 % molasses reduced the DM content from 252.4 g/kg in ECF to 238.9 g/ kg in ECFM and increased with 5 % caged layer waste (ECFP) to 267.6 g/kg. The CP content of ECF was 207.6 g/kg and this decreased to 198.5 g/kg DM in ECFM. Addition of molasses and caged layer waste caused a reduction in the HCN contents from 95.8 mg/kg in non-additive silage (ECF) to 89.3 mg/kg in ECFP and 84.7 mg/kg in ECFM. The mean pH of non-additive silage of 3.66 was significantly (p<0.05) different from the value of 4.29 in ECFP. Animals fed silage ensiled with molasses (ECFM) had a DM intake of 503.42 g/d, followed by values of 485.17 g/d and 458.43 g/d for animals fed ECF and ECFP respectively. Crude protein intake was similar in ECF and ECFM but higher (p<0.05) than ECFP and ranged from 161.28-172.71 g/d. The ruminal fluid parameters indicated no significant differences (p>0.05) in the pH, BC and lactic acid concentration in both the nonadditive and additive silages. Ammonia-nitrogen concentration (NH3-N) however, ranged significantly (p<0.05) from 15.93 ± 0.20 (mg/dL) in ECF to 22.43 ± 0.61 (mg/dL) in ECFP. The study showed that ensiling cassava leaves with 5 % molasses and caged layer waste improved the silage conditions and the ruminal fluid parameters of West African Dwarf goats. [ABSTRACT FROM AUTHOR]

Introduction: Chronic ß-alanine (BA) supplementation is an increasingly popular nutritional strategy, because it can elevate muscle carnosine content and thereby enhance high-intensity exercise performance. The current study investigated 1) whether sex and body mass are determinants of BA- induced muscle carnosine loading and 2) the optimal maintenance dose for ensuring constantly elevated muscle carnosine stores. Methods: During the loading phase, 34 participants (men and women) were supplemented with 3.2 g (4 x 800 mg) BA per day for 46 d (slightly different loading strategies were applied concerning the effect of meal timing and supplementation form). Thereafter, 19 participants (men and women) continued taking free-powder BA for six more weeks (maintenance phase). The participants were matched and redivided into three groups receiving 0.4, 0.8, and 1.2 g⋅d-1 BA, respectively. Muscle carnosine content was measured in the soleus and gastrocnemius muscles using proton magnetic resonance spectroscopy. Results: Body mass and sex had only minimal effect on the absolute increase in muscle carnosine. Given the lower baseline values in women, the relative increase for women was higher, indicating that women required less BA for the same relative increase. In addition, a significant negative correlation was observed between body mass and the relative increase in muscle carnosine (r = -0.45, P = 0.007). A maintenance dose of ~1.2 g⋅d-1 BA was the most effective in keeping muscle carnosine content elevated at the postsupplementation level. Conclusions: Sex and body mass did not markedly affect the absolute increase during muscle carnosine loading, although they are determinants for the relative increase. In addition, we established for the first time an effective maintenance dose of ~1.2 g⋅d-1 BA to keep muscle carnosine content elevated at 30%- 50% above baseline for a prolonged period. [ABSTRACT FROM AUTHOR]

For the most part, research and evaluations of disasters have lacked a standardised approach necessary to form a scientific basis for the discipline of health disaster. There has been an abundance of epidemiological research and quasi-scientific reports. However, for the most part, these have been devoid of rigorous scientific methodology. As such, it has been difficult to translate lessons learned in previous disasters into effective disaster prevention, mitigation, and interventions with a better outcome. Interventional research consists of evaluations of responses (actions) during and following disasters or evaluations of preparedness actions. Moreover, disaster research has been spread widely among a host of peer-reviewed journals in various disciplines. A substantial portion of the information on disaster management and response currently available resides in the grey literature in the form of after-action reports and projects provided by intergovernmental organisations such as United Nations agencies and non-governmental organisations. Most of the peer-reviewed disaster literature has been in the form of case reports.These factors have contributed to the difficulty in synthesising the findings and have impaired the development of the science of health disaster. The lack of a common terminology for health disaster further impedes the development of the science. Thus, we have not optimised our ability to prevent destructive events from occurring (when possible), mitigate the damage resulting from such events, and/or optimise the responses to a disaster, when they occur.In an effort to provide the structure needed to develop the science associated with disaster health, four frameworks have been proposed in these Guidelines: (1) conceptual; (2) structural; (3) operational; and (4) scientific. The first three frameworks provide the common language and the deconstruction of the elements involved in or present in a disaster scenario. The structural framework is further divided into two main parts, the longitudinal and the transectional structure. The last framework addresses the applicable scientific methods and how to translate this science to the stakeholders to be incorporated into actionable plans. The identification of key generic structures is essential for understanding the pathophysiology of disasters and the preparedness for, as well as the responses to them. Further, the essential concepts of priorities, interrelationships, administration, assessments, identification of needs, selection and planning of interventions, implementation, evaluation, and information are described in separate chapters.A consensus must be sought for a commonly accepted terminology for health disaster research. [ABSTRACT FROM PUBLISHER]