Development of Drug-Loaded PCL@MOF Film Enclosed in a Photo Polymeric Container for Sustained Release.

The programmed fabrication of oral dosage forms is associated with several challenges such as controlled loading and disintegration. To optimize the drug payload, excipient breakdown, and site-specific sustained release of hydrophobic drug (sulfamethoxazole, SM), we propose the development of acrylate polymer tablets enclosed with drug-loaded polycaprolactone (PCL) films. The active pharmaceutical ingredient (API) is physisorbed into the porous iron (Fe)-based metal-organic framework (MOF) and later converted to tangible PCL films, which, upon folding, are incorporated into the acrylate polymer matrices (P1/P2/P3). X-ray powder diffraction (XRPD) analysis and scanning electron microscopy (SEM) micrographs confirmed the stability and homogeneous distribution of MOF within the 50 µm thick film. Adsorption-desorption measurements at ambient temperatures confirmed the decrease in the BET surface area of PCL films by 40%, which was ∼3.01 m/g, and pore volume from 30 to 9 nm. The decrease in adsorption and surface parameters could confirm the gradual accessibility of SM molecules once exposed to a degrading environment. Fourier transform infrared (FTIR) analyses of in vitro dissolution confirmed the presence of the drug in the MOF-PCL film-enclosed tablets and concluded the cumulative SM release at pH ∼ 8.2 which followed the order SM@Fe-MOF < P1/P2/P3 < PCL-SM@Fe-MOF < P1/PCL-SM@Fe-MOF < P3/PCL-SM@Fe-MOF. The results of the study indicate that the P3/PCL-SM@Fe-MOF assembly has potential use as a biomedical drug delivery alternative carrier for effective drug loading and stimuli-responsive flexible release to attain high bioavailability.

Interrupting marine fouling with active buffered coatings.

Biofouling on marine surfaces causes immense material and financial harm for maritime vessels and related marine industries. Previous reports have shown the effectiveness of amphiphilic coating systems based on poly(dimethylsiloxane) (PDMS) against such marine foulers. Recent studies on biofouling mechanisms have also demonstrated acidic microenvironments in biofilms and stronger adhesion at low-pH conditions. This report presents the design and utilization of amphiphilic polymer coatings with buffer functionalities as an active disruptor against four different marine foulers. Specifically, this study explores both neutral and zwitterionic buffer systems for marine coatings, offering insights into coating design. Overall, these buffer systems were found to improve foulant removal, and unexpectedly were the most effective against the diatom Navicula incerta.

An Insulin-Modified pH-Responsive Nanopipette Based on Ion Current Rectification.

The properties of nanopipettes largely rely on the materials introduced onto their inner walls, which allow for a vast extension of their sensing capabilities. The challenge of simultaneously enhancing the sensitivity and selectivity of nanopipettes for pH sensing remains, hindering their practical applications. Herein, we report insulin-modified nanopipettes with excellent pH response performances, which were prepared by introducing insulin onto their inner walls via a two-step reaction involving silanization and amidation. The pH response intensity based on ion current rectification was significantly enhanced by approximately 4.29 times when utilizing insulin-modified nanopipettes compared with bare ones, demonstrating a linear response within the pH range of 2.50 to 7.80. In addition, insulin-modified nanopipettes featured good reversibility and selectivity. The modification processes were monitored using the I-V curves, and the relevant mechanisms were discussed. The effects of solution pH and insulin concentration on the modification results were investigated to achieve optimal insulin introduction. This study showed that the pH response behavior of nanopipettes can be greatly improved by introducing versatile molecules onto the inner walls, thereby contributing to the development and utilization of pH-responsive nanopipettes.

Computational Approach for the Development of pH-Selective PD-1/PD-L1 Signaling Pathway Inhibition in Fight with Cancer.

Immunotherapy, particularly targeting the PD-1/PD-L1 pathway, holds promise in cancer treatment by regulating the immune response and preventing cancer cells from evading immune destruction. Nonetheless, this approach poses a risk of unwanted immune system activation against healthy cells. To minimize this risk, our study proposes a strategy based on selective targeting of the PD-L1 pathway within the acidic microenvironment of tumors. We employed in silico methods, such as virtual screening, molecular mechanics, and molecular dynamics simulations, analyzing approximately 10,000 natural compounds from the MolPort database to find potential hits with the desired properties. The simulations were conducted under two pH conditions (pH = 7.4 and 5.5) to mimic the environments of healthy and cancerous cells. The compound MolPort-001-742-690 emerged as a promising pH-selective inhibitor, showing a significant affinity for PD-L1 in acidic conditions and lower toxicity compared to known inhibitors like BMS-202 and LP23. A detailed 1000 ns molecular dynamics simulation confirmed the stability of the inhibitor-PD-L1 complex under acidic conditions. This research highlights the potential of using in silico techniques to discover novel pH-selective inhibitors, which, after experimental validation, may enhance the precision and reduce the toxicity of immunotherapies, offering a transformative approach to cancer treatment.

Prevalence of Gastroesophageal Reflux Disease in Congenital Diaphragmatic Hernia Survivors From Infancy to Adulthood.

BACKGROUND: Gastroesophageal reflux disease (GERD) is a common comorbidity associated with congenital diaphragmatic hernia (CDH), with reported cases of Barrett's esophagus (BE) and esophageal adenocarcinoma before the age of 25. The prevalence and natural course of GERD in CDH survivors remain uncertain due to variations in diagnostic methods. We aimed to analyse the GERD prevalence from infancy through young adulthood. METHODS: We retrospectively analyzed pH-impedance measurements and endoscopic findings in 96 CDH survivors evaluated as routine care using well established clinical protocols. GERD was defined as an abnormal acid exposure time for pH-MII measurements and as presence of reflux esophagitis or BE at upper endoscopy. Clinical data including symptoms at time of follow-up and use of antireflux medication were collected. RESULTS: GERD prevalence remained consistently low (≤10%) across all age groups, yet many patients experienced GER symptoms. Histological abnormalities were observed in 80% of adolescents and young adults, including microscopic esophagitis in 50%. BE was diagnosed in 7% before the age of 18, all had GER symptoms. CDH severity, anatomy at the time of CDH correction, alcohol usage, and smoking did not emerge as significant risk factors for GERD. CONCLUSIONS: Given the low GERD prevalence in CDH survivors, a symptom-driven approach to diagnosis and follow-up is warranted. We advise long-term follow-up for all adult patients due to the early onset of BE and the limited evidence available. The longitudinal course and impact of GERD on other long-term CDH-related comorbidities should be explored in larger cohorts. LEVEL OF EVIDENCE: Not applicable.

A review on the role of pH-sensitive natural pigments in biopolymers based intelligent food packaging films.

As food packaging evolves, consumer interests are shifting from traditional to intelligent food packaging systems. Intelligent packaging includes active components that display changes in a visual or interactive form perceivable by consumers. This offers real-time monitoring of the quality and shelf life of the packaged food and enhances transparency. For example, pH-sensitive natural pigment-based films change color in response to variations in pH levels, enabling the film/labels to reflect alterations in the acidity or basicity of the food inside the package. Natural pigments like anthocyanins, curcumin, betalains, chlorophyll, and carotenoids have been comprehensively reported for developing biodegradable pH-sensitive films of starch, protein, chitosan, and cellulose. Natural pigments offer great compatibility with these biopolymers and improve the other performance parameters of the films. However, these films still lack the strength and versatility of petroleum-based synthetic plastic films. But these films can be used as an indicator and combined with primary packaging to monitor freshness, time-temperature, and leak for muscle foods, dairy products, fruits and vegetables, and bakery products. Therefore, this review provides a detailed overview of pH-sensitive pigments, their compatibility with natural polymers, their role in film performance in monitoring, and their food packaging applications.

Impact of Reduced Acidic Earwax pH and Earwax-Determinant Genotypes in Acquired Middle Ear Cholesteatoma.

OBJECTIVE: The development of acquired middle ear cholesteatoma is associated with a single nucleotide polymorphism, 538G>A, in the human adenosine triphosphate-binding cassette transporter C11 (ABCC11) gene, which is a determinant of the earwax morphotype, such as wet- and dry-type earwax; however, the mechanism underlying this association is unclear. We focused on the earwax pH and aimed to elucidate the mechanism between ABCC11 genotypes and acquired middle ear cholesteatoma. STUDY DESIGN: Prospective observational study. SETTING: Single-center, academic hospital. METHODS: We recruited 40 patients with acquired middle ear cholesteatoma who underwent surgery and 115 controls with no history of middle ear cholesteatoma. We assessed the earwax pH and ABCC11 genotypes in all participants. Clinical information was collected from the patients with cholesteatoma. RESULTS: The earwax pH was significantly less acidic in patients with cholesteatoma and those carrying wet earwax genotypes (ABCC11 538G/G or 538G/A) than in the controls and those carrying the dry earwax genotype (ABCC11 538A/A), respectively. Furthermore, earwax pH was significantly positively correlated with high preoperative cholesteatoma stages in the patients with cholesteatoma. CONCLUSION: Our results show that the less acidic earwax pH was significantly related to the development and progression of acquired middle ear cholesteatoma. The less acidic earwax pH may play an important role in the mechanism underlying the association between acquired middle ear cholesteatoma and the ABCC11 gene at site 538.

pH-Responsive Mesoporous Silica Nanoparticles Loaded with Naringin for Targeted Osteoclast Inhibition and Bone Regeneration.

Background: It is well-established that osteoclast activity is significantly influenced by fluctuations in intracellular pH. Consequently, a pH-sensitive gated nano-drug delivery system represents a promising therapeutic approach to mitigate osteoclast overactivity. Our prior research indicated that naringin, a natural flavonoid, effectively mitigates osteoclast activity. However, naringin showed low oral availability and short half-life, which hinders its clinical application. We developed a drug delivery system wherein chitosan, as gatekeepers, coats mesoporous silica nanoparticles loaded with naringin (CS@MSNs-Naringin). However, the inhibitory effects of CS@MSNs-Naringin on osteoclasts and the underlying mechanisms remain unclear, warranting further research. Methods: First, we synthesized CS@MSNs-Naringin and conducted a comprehensive characterization. We also measured drug release rates in a pH gradient solution and verified its biosafety. Subsequently, we investigated the impact of CS@MSNs-Naringin on osteoclasts induced by bone marrow-derived macrophages, focusing on differentiation and bone resorption activity while exploring potential mechanisms. Finally, we established a rat model of bilateral critical-sized calvarial bone defects, in which CS@MSNs-Naringin was dispersed in GelMA hydrogel to achieve in situ drug delivery. We observed the ability of CS@MSNs-Naringin to promote bone regeneration and inhibit osteoclast activity in vivo. Results: CS@MSNs-Naringin exhibited high uniformity and dispersity, low cytotoxicity (concentration≤120 µg/mL), and significant pH sensitivity. In vitro, compared to Naringin and MSNs-Naringin, CS@MSNs-Naringin more effectively inhibited the formation and bone resorption activity of osteoclasts. This effect was accompanied by decreased phosphorylation of key factors in the NF-κB and MAPK signaling pathways, increased apoptosis levels, and a subsequent reduction in the production of osteoclast-specific genes and proteins. In vivo, CS@MSNs-Naringin outperformed Naringin and MSNs-Naringin, promoting new bone formation while inhibiting osteoclast activity to a greater extent. Conclusion: Our research suggested that CS@MSNs-Naringin exhibited the strikingly ability to anti-osteoclasts in vitro and in vivo, moreover promoted bone regeneration in the calvarial bone defect.

Response of N, P, and metal ions in deep soil layers to long-term cultivation of rubber and rubber-based agroforestry systems.

The growing demand for natural rubber products has driven the expansion of rubber plantations in recent decades. While much attention has been given to studying the long-term effects of rubber and rubber-based agroforestry systems on surface soil properties, there has been a tendency to overlook changes in soil properties in deeper layers. Our study addresses this gap by examining alterations in nitrogen (N), phosphorus (P), and metal ion levels in deep soil layers resulting from the prolonged cultivation of rubber and rubber-based agroforestry systems. We found notable shifts in soil NH4+ and NO3- concentrations within the 0-30 cm soil layer across different-aged rubber and rubber-based agroforestry systems. Particularly in mature systems, NO3- and available P levels were close to zero below 30 cm soil depth. Introducing Flemingia macrophylla into young rubber plantations increased soil NH4+ and NO3- in the 0-90 cm soil layer and available P in the 0-10 cm soil layer. Over the long term, cultivation of rubber plantations increased the depletion of total P in the 0-50 cm soil layer, available iron (Fe) and manganese (Mn) in the 30-90 cm soil layer, available copper (Cu) and zinc (Zn) in the 0-90 cm soil layer, accompanied by a decrease in soil pH and increase in exchangeable aluminum (Al) in the 0-90 cm soil layer. Notably, soil exchangeable Al levels exceeding 2.0 cmol kg-1 appeared to induce aluminum toxicity. Furthermore, soil pH below 5.2 triggered a sharp release of exchangeable Al within the 0-90 cm soil layer of rubber plantations, with soil available P nearing zero when exchangeable Al levels assed 7.3 cmol kg-1. Our findings underscore the profound impact of long-term rubber plantation cultivation on surface and deep soil properties. Addressing soil degradation in these deep soil layers poses significant challenges for future soil restoration efforts.

Automated software-derived supine baseline impedance is highly correlated with manual nocturnal baseline impedance for the diagnosis of GERD.

BACKGROUND: Mean nocturnal baseline impedance (MNBI) can improve diagnostic accuracy for gastroesophageal reflux disease (GERD), but must be manually calculated and is not routinely reported. We aimed to determine how automated software-derived mean supine baseline impedance (MSBI), a potential novel GERD metric, is related to MNBI. METHODS: Consecutively obtained pH-impedance studies were assessed. Manually extracted MNBI was compared to MSBI using paired t-test and Spearman's correlations. KEY RESULTS: The correlation between MNBI and MSBI was very high (ρ = 0.966, p < 0.01). CONCLUSIONS & INFERENCES: The ease of acquisition and correlation with MNBI warrant the routine clinical use and reporting of MSBI with pH-impedance studies.

Investigating the effects of cytokine biomarkers on HIV incidence: a case study for individuals randomized to pre-exposure prophylaxis vs. control.

Introduction: Understanding and identifying the immunological markers and clinical information linked with HIV acquisition is crucial for effectively implementing Pre-Exposure Prophylaxis (PrEP) to prevent HIV acquisition. Prior analysis on HIV incidence outcomes have predominantly employed proportional hazards (PH) models, adjusting solely for baseline covariates. Therefore, models that integrate cytokine biomarkers, particularly as time-varying covariates, are sorely needed. Methods: We built a simple model using the Cox PH to investigate the impact of specific cytokine profiles in predicting the overall HIV incidence. Further, Kaplan-Meier curves were used to compare HIV incidence rates between the treatment and placebo groups while assessing the overall treatment effectiveness. Utilizing stepwise regression, we developed a series of Cox PH models to analyze 48 longitudinally measured cytokine profiles. We considered three kinds of effects in the cytokine profile measurements: average, difference, and time-dependent covariate. These effects were combined with baseline covariates to explore their influence on predictors of HIV incidence. Results: Comparing the predictive performance of the Cox PH models developed using the AIC metric, model 4 (Cox PH model with time-dependent cytokine) outperformed the others. The results indicated that the cytokines, interleukin (IL-2, IL-3, IL-5, IL-10, IL-16, IL-12P70, and IL-17 alpha), stem cell factor (SCF), beta nerve growth factor (B-NGF), tumor necrosis factor alpha (TNF-A), interferon (IFN) alpha-2, serum stem cell growth factor (SCG)-beta, platelet-derived growth factor (PDGF)-BB, granulocyte macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), and cutaneous T-cell-attracting chemokine (CTACK) were significantly associated with HIV incidence. Baseline predictors significantly associated with HIV incidence when considering cytokine effects included: age of oldest sex partner, age at enrollment, salary, years with a stable partner, sex partner having any other sex partner, husband's income, other income source, age at debut, years lived in Durban, and sex in the last 30 days. Discussion: Overall, the inclusion of cytokine effects enhanced the predictive performance of the models, and the PrEP group exhibited reduced HIV incidences compared to the placebo group.

The Fusicoccin story revisited.

In plant biology Fusicoccin (FC) is one of the most studied fungal metabolites to date. Since the structural identification in 1964, much has been learned about its effects on the physiology of plants, about the interference with the action of plant hormones, the molecular nature of the plant receptor(s) for FC and the biosynthetic pathway for FC in the fungus. The finding that the plasma membrane H+-ATPase in combination with 14-3-3 proteins acts as high-affinity receptor for FC was a breakthrough in the field. Ever since, the binding of FC to the ATPase|14-3-3 receptor has taken center stage in explaining all FC induced physiological effects. However, a more critical review shows that this is not at all evident for a number of FC induced effects. Examples of this are: the inhibition of outward rectifying K+-channels in guard cells, the phosphorylation/activation of PEP-carboxylase and malate accumulation, the antagonism with ABA induced production of H2O2 / NO and the effect on ethylene production. In addition, recently two other physiological processes were shown to be targeted by FC, viz. the activation of TORC1 and the interference of FC with the immune response to fungal elicitors. In this review, the notion will be challenged that all FC affected processes start with the binding to and activation of the PM-ATPase and the question is raised whether may be other proteins with a key role in the respective processes are directly targeted by FC. A second unresolved question is whether FC may be another example of a fungal molecule turning out to be a 'copy' of an as yet unknown plant molecule; in analogy to the fungal product and plant hormone gibberellic acid. A relevant question in this respect is whether it is a coincidence that proteins that act in a coordinated fashion during stomatal opening (the ATPases and K+-channels) are targeted by FC? Or are the sites where FC binds in the plant, conserved during evolution because they serve a physiological role, namely the accommodation of a plant produced molecule? In view of the evidence, albeit not conclusive, that plants indeed produce 'FC-like ligands', it is worthwhile to make a renewed attempt with current day improved technology to answer this question and may be upgrade FC or structural analogue(s) to a new level, the level of plant hormone.

Inconsistency of in vitro exsheathment triggers for gastrointestinal nematode parasites of sheep, cattle and deer.

Exsheathment is crucial in the transition from free-living to parasitic phase for most strongyle nematode species. A greater understanding of this process could help in developing new parasitic control methods. This study aimed to identify commonalities in response to exsheathment triggers (heat acclimation, CO2 and pH) in a wide range of species (Haemonchus contortus, Trichostrongylus spp., Cooperia spp., Oesophagostomum spp., Chabertia ovina, and members of the subfamily Ostertagiinae) from sheep, cattle and farmed deer. The initial expectation of similarity in pH requirements amongst species residing within the same organ was not supported, with unexpected pH preferences for exsheathment of Trichostrongylus axei, Trichostrongylus vitrinus, Trichostrongylus colubriformis and Cooperia oncophora. We also found differences between species in their response to temperature acclimation, with higher exsheathment in response to heat shock observed for H. contortus, Ostertagia ostertagi, T. axei, T. vitrinus and Oesophagostomum sikae. Furthermore, some species showed poor exsheathment under all experimental conditions, such as Cooperia curticei and the large intestinal nematodes C. ovina and Oesophagostomum venulosum. Interestingly, there were some significant differences in response depending on the host from which the parasites were derived. The host species significantly impacted on the exsheathment response for H. contortus, Teladorsagia circumcincta, T. vitrinus and T. colubriformis. Overall, the data showed variability between nematode species in their response to these in vitro exsheathment triggers, highlighting the complexity of finding a common set of conditions for all species in order to develop a control method based on triggering the exsheathment process prematurely.

Evaluation of the Protective Effects of Lugol's Solution in Rats Poisoned with Aluminum Phosphide (Rice Tablets).

Aluminum phosphide (AlP) is the main component of rice tablets (a pesticide), which produces phosphine gas (PH3) when exposed to stomach acid. The most important symptoms of PH3 toxicity include, lethargy, tachycardia, hypotension, and cardiac shock. It was shown that Iodine can chemically react with PH3, and the purpose of this study is to investigate the protective effects of Lugol solution in poisoning with rice tablets. Five doses (12, 15, 21, 23, and 25 mg/kg) of AlP were selected, for calculating its lethal dose (LD50). Then, the rats were divided into 4 groups: AlP, Lugol, AlP + Lugol, and Almond oil (as a control). After 4 h, the blood pressure and electrocardiogram (ECG) were recorded, and blood samples were obtained for biochemical tests, then liver, lung, kidney, heart, and brain tissues were removed for histopathological examination. The results of the blood pressure showed no significant changes (P > 0.05). In ECG, the PR interval showed a significant decrease in the AlP + Lugol group (P < 0.05). In biochemical tests, LDH, Ca2+, Creatinine, ALP, Mg2+, and K+ represented significant decreases in AlP + Lugol compared to the AlP group (P < 0.05). Also, the administration of Lugol's solution to AlP-poisoned rats resulted in a significant decrease in malondialdehyde levels and a significant increase in catalase activity (P < 0.05). Histopathological evaluation indicates that Lugol improves changes in the lungs, kidneys, brain, and heart. Our results showed that the Lugol solution could reduce tissue damage and oxidative stress in AlP-poisoned rats. We assume that the positive effects of Lugol on pulmonary and cardiac tissues are due to its ability to react directly with PH3.

International collaborative study to assess new stocks of candidate reference preparations to control the level of anti-D in IVIG

The level of anti-D antibodies in human immunoglobulin products for intravenous administration (IVIG) is controlled by the direct haemagglutination method prescribed by the European Pharmacopoeia (Ph. Eur.) that requires 2 control reference reagents. The World Health Organization (WHO) positive control International Reference Reagent (IRR; 02/228) with a nominal titre of 8 defines the highest acceptable titre, while the negative control preparation (02/226) has a nominal titre of <2. Working reference preparations (04/132 and 04/140) were subsequently established as Biological Reference Preparations (BRPs) for the Ph. Eur., and for distribution by the United States Food and Drug Administration (US FDA) and the National Institute for Biological Standards and Control (NIBSC). Due to diminishing stocks of these working reference preparations across the 3 institutions, a joint international study was organised to establish harmonised replacement batches. Sixteen laboratories contributed data to the study to evaluate positive and negative candidate replacement batches (13/148 and 12/300, respectively) against the WHO positive and negative control IRRs and the current working reference preparations (BRPs). The results show that the candidate reference preparations (13/148 and 12/300) are indistinguishable from the corresponding IRRs and current BRPs. The candidate preparations 13/148 and 12/300 were adopted by the Ph. Eur. Commission as Immunoglobulin (anti-D antibodies test) BRP batch 2 and Immunoglobulin (anti-D antibodies test negative control) BRP batch 2 with nominal haemagglutination titres of 8 and <2, respectively. The same materials were also adopted as NIBSC and US FDA reference preparations, thus ensuring full harmonisation.

Fluctuations in equine cutaneous pH and transepidermal water loss with time of day and ambient conditions.

Cutaneous pH and transepidermal water loss (TEWL) are commonly utilized measures in dermatological research as they provide information concerning barrier function. The importance of dermal health has become more evident in recent years. Accordingly, the aim of this work was to identify natural fluctuations in the biophysical parameters of healthy equine skin. Cutaneous pH and TEWL was collected on nine mares at 6:00 AM, 12:00 PM, and 6:00 PM daily for five days on the nose, withers, girth area, mid-back, and base of tail. Ambient temperature and humidity were measured at each collection. Statistical analysis was completed using SAS On Demand. Tests included repeated measures, ANOVA, and regression analysis. Mean cutaneous pH significantly differed by day (P = 0.0052) and time (P = 0.0073) but was unaffected by anatomical location (P = 0.2841). Interestingly, cutaneous pH had a significant interaction of day and location (P = 0.0004). Mean TEWL measures significantly differed by day (P < 0.0001), time (P < 0.0001), and anatomical location (P = 0.0231). Interaction of day and time had a significant effect on TEWL (P < 0.0001) and also resulted in a three-way interaction of day, time, and location (P = 0.0167). There were no significant associations of pH with temperature and humidity. All measures of TEWL across all locations were significantly correlated with temperature and humidity (P < 0.0001). Cutaneous pH and TEWL measures are affected by environmental conditions which should be considered in future models and work using dermal characteristics of horses.

Comparing microbial populations from diverse hydrothermal features in Yellowstone National Park: hot springs and mud volcanoes.

Geothermal features, such as hot springs and mud volcanoes, host diverse microbial life, including many extremophile organisms. The physicochemical parameters of the geothermal feature, such as temperature, pH, and heavy metal concentration, can influence the alpha and beta diversity of microbial life in these environments, as can spatiotemporal differences between sites and sampling. In this study, water and sediment samples were collected and analyzed from eight geothermal sites at Yellowstone National Park, including six hot springs, a mud volcano, and an acidic lake within the same week in July 2019, and these geothermal sites varied greatly in their temperature, pH, and chemical composition. All samples were processed and analyzed with the same methodology and taxonomic profiles and alpha and beta diversity metrics determined with 16S rRNA sequencing. These microbial diversity results were then analyzed with respect to pH, temperature, and chemical composition of the geothermal features. Results indicated that predominant microbial species varied greatly depending on the physicochemical composition of the geothermal site, with decreases in pH and increases in dissolved heavy metals in the water corresponding to decreases in alpha diversity, especially in the sediment samples. Similarly, sites with acidic pH values had more similar microbial populations (beta diversity) to one another than to relatively neutral or alkaline pH geothermal sites. This study suggests that pH and/or heavy metal concentration is a more important driver for microbial diversity and population profile than the temperature for these sites and is also the first reported microbial diversity study for multiple geothermal sites in Yellowstone National Park, including the relatively new mud volcano Black Dragon's Caldron, which erupted in 1948.

Properties of encapsulated raspberry powder and its efficacy for improving the pH, colour quality and shelf life of modified atmosphere packaged chicken nuggets.

1. Recent research has shown that encapsulated raspberry powder (RP) is a natural colourant for foodstuffs. However, no research has been conducted on its use in chicken nuggets. In addition, the effect of RP on products with and without phosphate addition is unknown. This study assessed the effects of RP (control, 0.5%, 1.0%) and phosphate (0.0%, 0.3%) on the pH and colour quality properties of nuggets.2. In the production of RP, red raspberry (Rubus ideaus L.) juices were encapsulated using maltodextrin in a spray-dryer. Antioxidant activity, total anthocyanin, total phenolics, colour, moisture and pH analyses of the RP were performed.3. Nuggets were packaged in modified atmosphere packaging (MAP; 40%CO2 + 60%N2) and were stored at 2.0 ± 0.5°C for 120 d. The pH and external and internal surface colour (L*, a*, b*, C* and h) values were measured on d 0, 15, 30, 45, 60, 75, 90, 105 and 120 of storage.4. The addition of phosphate increased the pH in the samples, while these decreased with the addition of RP (p < 0.05). During storage, the highest pH were seen in the phosphate samples and the lowest in the nuggets with 1.0% RP addition (p < 0.05).5. With the addition of phosphate, the external surface a* value of nuggets increased (p < 0.05). Depending on the level of RP added to the nuggets, the external surface L* value decreased and a* and b* values increased (p < 0.05). After d 30 of storage, the a* value increased in the samples with RP addition and this increase was higher in the with phosphate nuggets (p < 0.05).6. The internal surface a* value increased with the addition of RP during nugget production (p < 0.05). The increase in a* value was greater in samples with added phosphate (p < 0.05). During storage, the highest a* values were seen in nuggets treated with phosphate + 0.1% RP (p < 0.05). The addition of RP to chicken nugget emulsion improved redness, colour stability and shelf life.

Predicting the evolution of pH and total soluble solids during coffee fermentation using near-infrared spectroscopy coupled with chemometrics.

Currently, coffee fermentation is visually operated, which results in incomplete or excessive processes and coffees with undesirable characteristics. In front of it, pH and total soluble solids (TSS) have been shown to be good fermentation indicators, although this requires rapid, accurate, and chemical-free measurement techniques such as NIR spectroscopy. However, the complexity of the NIR spectra requires optimization steps in which variable selection techniques simplify profiles and subsequent models. This work tests a new covering array feature selection (CAFS) approach on NIR spectra to optimize prediction models in coffee samples during fermentation. Spectral profiles in the range 1100-2100 nm were extracted from coffee beans (Typica, Caturra, and Catimor varieties) raw and during fermentation (4, 8, 12, 16, 20, and 24 h). Partial least-squares regressions (PLSR) were performed using full spectra using a five-fold cross-validation strategy for training and validation. The relevant wavelengths were then selected using the ß coefficients, the important projection of variables (VIP), and the CAFS method. Finally, optimized models were performed using the relevant wavelengths and compared among these using their statistical metrics. The models performed using the selected variables (22-47) of CAFS showed the best performance in predicting pH (R 2 = 0.825-0.903, RMSE = 0.096-0.158, RPD = 6.33-10.38) and TSS (R 2 = 0.865-0.922, RMSE = 0.688-1.059, RPD = 0.94-1.45) compared to the other methods. These findings suggest that simple and efficient models could be performed and implemented in routine analysis due to the maximum coverage and minimum cardinality of CAFS.