Volume Of Solution Research Articles

Constructing osteo-inductive bio-ink for 3D printing through hybridization of gelatin with maleic acid modified bacterial cellulose by regulating addition volumes of maleic acid solution

Bacterial cellulose (BC) is an exopolysaccharide with unique properties that has been applied in various fields. However, the dense and intertwined nature of BC fibers limits its use in certain applications, including 3D printing scaffolds for bone regeneration. In this work, a controllable BC-based bio-ink for 3D printing was successfully prepared by modifying the neat BC through maleic acid (MA) treatment, aiming to promote bone tissue regeneration. To achieve homogeneous BC dispersions while preserving its crystalline and chemical properties, BC was modified by MA solution (60 %, w/V) with solid-liquid ratio from 1꞉5 to 1꞉50 (w/V) to obtain MA-BC dispersions. The analysis results from microstructure, chemical group, crystallinity, and wettability indicated that the BC/MA solution with ratio of 1꞉30 demonstrated the best pre-treatment performance to obtain MA-BC. Subsequently, by combining MA-BC with gelatin, we successfully formulated MA-BC-GEL gels with favorable rheological properties and compression modulus, which can be used as promising bio-inks for 3D bioprinting applications. In vitro tests demonstrated 1꞉30 MA-BC possessed excellent biocompatibility, a significant ability to express the alkaline phosphatase gene and osteogenic-related genes, and facilitated the formation of mineralized nodules. The utilization of this novel bio-ink in scaffold preparation for bone regeneration highlights the promising application of modified BC in bone tissue engineering field.

Synthesis and characterization of chitosan-based pH-sensitive biofilm: An experimental design approach for release of vitamin B12

Hydrogels because of their unique potentials, such as highwater content and hydrophilicity, are of interest for the controlled release of drug molecules. In the present study, a biofilm was produced using chitosan, a natural polymer. Characterization analyses of the synthesized biofilm were performed using Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis-differential thermal analysis, x-ray diffraction, and scanning electron microscopy-energy dispersive x-ray spectrometry. The analysis results of the film before loading were compared to the analysis made after adding vitamin B12 to the film. The release percentage of vitamin B12 was investigated by using ultraviolet-visible spectrophotometery. The FT-IR bands of vitamin B12 were in the range of 2,800-3,500 cm-1 and 1,000 cm-1-1,750 cm-1. When pH increased from 3 to 7, release of vitamin B12 from the biopolymer increased up to pH 5. While examining the release potential, parameters, such as pH, initial concentration of vitamin B12, release time, and solution volume, were optimized by using response surface methodology. It was determined that with the increase in release time and the initial concentration, pH contributed positively to the release of vitamin B12. The following conditions were determined for release of vitamin B12 from the biofilm: pH: 4.2, initial concentration of vitamin B12: 54.0 mg L-1, the release time: 117 min, and volume of solution: 2.1 mL. The analysis of variance results showed that the determination coefficients for the use of synthesized biofilm in vitamin B12 release were high and R2 =0.9704.

Synthesis of struvite-enriched slow-release fertilizer using magnesium-modified biochar: Desorption and leaching mechanisms

To improve the retention and slow-release abilities of nitrogen (N) and phosphorus (P), an 82 %-purity struvite fertilizer (MAP-BC) was synthesized using magnesium-modified biochar and a solution with a 2:1 concentration ratio of NH4+ to PO43− at a pH of 8. Batch microscopic characterizations and soil column leaching experiments were conducted to study the retention and slow-release mechanisms and desorption kinetics of MAP-BC. The slow-release mechanism revealed that the dissolution rate of high-purity struvite was the dominant factor of NP slow release. The re-adsorption of NH4+ and PO43− by biochar and unconsumed MgO prolonged slow release. Mg2+ ionized by MgO could react with PO43− released from struvite to form Mg3(PO4)2. The internal biochar exhibited electrostatic attraction and pore restriction towards NH4+, while magnesium modification and nutrient loading formed a physical antioxidant barrier that ensured long-term release. The water diffusion experiment showed a higher cumulative release rate for PO43− compared to NH4+, whereas in soil column leaching, the trend was reversed, suggesting that soil's competitive adsorption facilitated the desorption of NH4+ from MAP-BC. During soil leaching, cumulative release rates of NH4+ and PO43− from chemical fertilizers were 3.55–3.62 times faster than those from MAP-BC. The dynamic test data for NH4+ and PO43− in MAP-BC fitted the Ritger-Peppas model best, predicting release periods of 163 days and 166 days, respectively. The leaching performances showed that MAP-BC reduced leaching solution volume by 5.58 % and significantly increased soil large aggregates content larger than 0.25 mm by 24.25 %. The soil nutrients retention and pH regulation by MAP-BC reduced leaching concentrations of NP. Furthermore, MAP-BC significantly enhanced plant growth, and it is more suitable as a NP source for long-term crops. Therefore, MAP-BC is expected to function as a long-term and slow-release fertilizer with the potential to minimize NP nutrient loss and replace part of quick-acting fertilizer.

Modeling and analysis of the triple diffusion unsteady flow of couple stress nanofluid with variable viscosity and distinct thermal sources

Thanks to their optimal thermal characteristics, nanomaterials stand out for their varied applications in heat transfer systems, energy storage, industrial processes, and biomedical research. Recently, scientists explored various dynamic properties in nanofluid flow to develop an even better thermal model. In this context, the phenomenon of triple diffusion in nanofluids constitutes an active area of research, offering promising applications in nanotechnology, metallurgical processes, chemical reactors, and thermo-diffusion processes. This paper analyzes the triple diffusion flow of a torque-constrained nanofluid, induced by a periodically oscillating porous surface, taking into account the importance of variations in thermal consequences. The viscosity of the torque-constrained nanofluid is assumed to be temperature-dependent. The analysis takes into account the variable role of thermal conductivity, mass diffusivity, and solute volume fraction. The modeling of the problem is expressed by coupled nonlinear partial differential equations. The semi-analytic technique, known as the homotopic analysis scheme, is used for resolution. The solution is validated and confirms the convergence region. The physical aspects of the parameters are examined with regard to the parameters involved. The simulated observations reveal that with the Dufour–Lewis factor and varying mass diffusivity, an increase in solute concentration is seen. The concentration of nanoparticles decreases with the nano-Lewis number.

Purification of process solutions from mercury by sorption

At JSC «Uralelectromed», selenium-containing raw materials and industrial products are processed, resulting in solutions containing a mixture of mercury with concentrations as follows (g/dm3): 157–210 Se; 0.004–0.02 Hg; 0.15–0.20 Te; 2–3 As; 0.15–0.20 Sb; and 45–50 S. To produce branded selenium, the mercury concentration in the solution must be kept below 0.001 g/dm3. Various methods, such ashydrometallurgical and electrochemical processes, are known for mercury purification from solutions. JSC «Uralelectromed» has selected sorption technology for mercury removal using the weak-base macroporous anionite Lewatit MP-68 (Germany), which allows for control over the degree of solution purification. In pursuit of import substitution for the Western European sorbent Lewatit MP-68, we investigated several pre-selected industrial sorbents for extracting mercury anionic complexes produced in Russia (AM-2B, AN-31, AV 17-8, VP-3Ap), China (Seplite MA 940 and LSC 710), and India (Tulsion CH-95 and CH-97). Initially, in static mode, we determined the distribution coefficient (Cd), the degree of element extraction (ε), the static exchange capacity of the resins (SEC, g/dm3), and the mercury/selenium separation coefficient (DHg/Se) which led to the selection of the best samples: AV 17-8, Seplite MA 940, AM-2B, and CH-97, with SEC values of 0.95–0.97 g/dm3 (SEC = 0.98 g/dm3 of resin Lewatit MP-68). Subsequently, in dynamic mode, we ranked the ionites by decreasing dynamic exchange capacity (DEC / TDEC): AV 17-8 ≥ Lewatit MP-68 > AM-2B > Seplite MA 940 > Tulsion CH-97. Resins AV 17-8, Seplite MA 940, and AM-2B demonstrated similar dynamic sorption characteristics; under comparable conditions, mercury breakthrough occurred after processing at least 950 specific volumes of the initial solution. In contrast, with Lewatit MP-68 ionite, mercury breakthrough occurred after no more than 750 specific volumes, indicating the need to increase the number of sorption steps in the solution purification cascade. Considering the totality of ion-exchange properties, for further industrial testing, it is recommended to use the domestically produced resin AV 17-8 instead of the foreign sorbent Lewatit MP-68 in the sorption purification process of selenic acid to remove mercury, thereby ensuring the production of branded selenium.

Application of kinetic models to study the sorption rate in the ‘ammonium ions–calcined sorbent’ system

This study examines sorption kinetics for the extraction of ammonium ions from an aqueous solution under static conditions using 5 g of sorbent. The sorbent was obtained by calcining ash and slag waste accumulated in the ash dump following hydraulic ash removal. The initial concentrations of ammonium ions in the model solutions were 5, 20, 50 and 100 mg/dm3. The volume of the model solution was 50 cm3. For each initial concentration, the kinetic curves of the ammonium ion sorption at the sorption duration of 10, 30, 60, 90, 120, 150 and 180 min were obtained. The kinetic curves were processed using the Lagergren (pseudo-first order), Ho and McKay (pseudo-second order), Morris-Weber (diffusion) and Elovich kinetic equations. It was demonstrated that all kinetic equations adequately describe the experimental data. The linear correlation of the equations was given. The Boyd equation was used to determine the limiting stage in the Morris–Weber model. It was established that the external diffusion mechanism is limiting for the sorption of ammonium ions by a calcined sorbent. The Lagergren model, with a coefficient of determination R2 of 0.9801–0.9949, best described the experimental data on sorption kinetics. Sorption rate curves as a function of the adsorption value and sorption time were given. The latter are described by exponential and polynomial dependence according to the Lagergren model, polynomial dependence according to the Ho and McKay model and exponential dependence according to the Morris–Weber and Elovich models. The sorption rate was the highest at the initial stage of sorption for all dependencies, which is consistent with previous studies on the sorption of pollutants from aqueous solutions using various sorbents.

Quantitative analysis of microplastics in water environments based on Raman spectroscopy and convolutional neural network

With the increasing interest in microplastics (MPs) pollutants, quantitative analysis of MPs in water environment is an important issue. Vibrational spectroscopy, represented by Raman spectroscopy, is widely used in MP detection because they can provide unique fingerprint characteristics of chemical components of MPs, but it is difficult to provide quantitative information. In this paper, an ingenious method for quantitative analysis of MPs in water environment by combining Raman spectroscopy and convolutional neural network (CNN) is proposed. It is innovatively proposed to collect the average mapping spectra (AMS) of the samples to improve the uniformity of Raman spectroscopy detection, and to increase the effective detection range of concentration by filtering different volumes of the same MP solutions. In order to verify the universality and effectiveness of the proposed method, 6 different sizes of Polyethylene (PE) MPs were used as detection objects and mixed into 5 different actual water environments. The R2 and RMSE of CNN for identifying the concentration of PE solutions could reach 0.9972 and 0.033, respectively. Meanwhile, by comparing machine learning models such as Random Forest (RF) and Support Vector Machine (SVM) were compared, and CNN combined with Raman spectroscopy has significant advantages in identifying the concentration of MPs.

A novel cloud point back-extraction of uranium(VI) from organic radioactive solution to slightly acidic aqueous medium

ABSTRACT Stripping back uranium(VI) from an organic radioactive solution to an aqueous medium was rendered simple and quantitative by an unprecedented cloud point back-extraction (CPEback) method. The concentration difference of nitrate ions in and out of the micelle was employed to change the uranium distribution coefficient in favor of the bulk aqueous phase. In addition, the monophasic nature of cloud point extraction and the complexing ability of oxalic acid with uranyl ion in the bulk aqueous phase resulted in the quantitative recovery of uranium in a single step. The CPEback parameters were optimized through a cross-optimization process and the recovered uranium was quantified by the biamperometric titration method. The proposed analytical procedure resulted in high back-extraction efficiency and recovery of (99.6 ± 0.2)% and 99.2%, respectively. The process turned large volumes of organic radioactive solution into small volumes of a less hazardous organic medium having high viscosity and negligible vapor pressure. Analysis of two real samples of ~17 and 165 mL organic radioactive solutions resulted in 99% and 98.2% uranium recoveries, respectively. The leftover organic phase containing the extractant and nonionic surfactant can now be easily stored or reused.

Electrodialysis of moderately concentrated solutions: Experiment and modeling based on a simplified characterization of ion-exchange membranes

Electrodialysis (ED) is a cost-effective and environmentally friendly process; it is considered a key step in Zero Liquid Discharge systems. However, the ED process producing a fairly concentrated solution is not well understood. An ED process where 10 L of 0.5 M NaCl was circulated in diluate stream (DS) and 0.1 L of initially 2.0 M NaCl circulated in concentrate stream (CS) was studied. The concentration of concentrate increased up to 3.5 M. The electrodialyzer's design eliminated current leakage. Ion-exchange membranes, MK-40, MA-41 (Shchekinoazot) and CJMA-3 (Chemjoy Polymer Materials), were characterized prior to ED. Based on the concentration dependences of membrane conductivity and diffusion permeability, the “true” (ti⁎) ion transport numbers in the membranes were found; the water transport number (tw) was found from volumetric measurements. It was shown that the current efficiency, η, found using ti⁎ is quantitatively consistent with η found in the ED experiments. To calculate the time dependences of solution concentration and volume in CS, a mathematical model was built. For the first time, ti⁎ and tw determined in independent experiments, were used as parameters. The only fitting parameter was the osmotic permeability coefficient. A good agreement with experimental results is obtained.

Probing molecular interactions of an anti-epileptic drug, sodium valproate in aqueous MgCl2 solutions

Study of the physicochemical properties of anti-epileptic drugs in the presence of cosolutes in aqueous solutions has been a subject of interest of researchers because of their interaction with biological membranes to employ their effect. Such properties provide complete information regarding solute-solute and solute-solvent type interactions. As electrolytes are essential components of biological systems, therefore the study of drug-electrolyte chemistry is important to understand the mechanism of drug action at the molecular level and hence useful in drug design and development processes. Therefore, in the current report, the density and sound velocity of an anti-epileptic drug sodium valproate (SV) in aqueous and in aqueous solutions of an electrolyte viz. MgCl2 (mB = 0.024, 0.047, 0.070 mol kg−1) at different temperatures (288.15, 298.15, 308.15, and 318.15 K) and at a pressure of 0.101 MPa were measured along with 1H NMR spectroscopy. Various volumetric and acoustical parameters such as apparent molar volume (Vφ) and isentropic compressibility (Kφ) of the solute, apparent molar volume (Vφ°) and isentropic compressibility (Kφ°) of solute at infinite dilution, apparent molar expansibility (Eφ°) and their double derivatives (∂2Vφ°/∂T2)P, transfer volumes (∆trVφ°), hydration number (nH), acoustic impedance (Z), intermolecular free length (Lf), Wada's constant (W) and Rao's constant (R) were calculated from density and sound velocity data. The variation in all these parameters with cosolute concentration indicates the existence of hydrophilic/ionic-ionic interactions at lower concentrations but hydrophobic-ionic interactions at higher concentrations of MgCl2. The 1H NMR spectroscopic results also support the existence of hydrophobic-ionic interactions at higher concentrations of MgCl2. The decrease in electrostriction but increase in hydrophobic hydration of solute molecules has also been seen with rise in temperature.

Tunning MIL-101(Cr) MOF polymorphism towards efficient adsorption and localized Fenton-like degradation of para-nitroaniline by Fe incorporation

The employment of metal–organic frameworks (MOFs) in the context of eliminating organic contaminants from water has garnered significant interest in contemporary research. This study investigated the impact of varying quantities of iron on the MIL-101(Cr) adsorbent. For the first time, a polymorphic Cr/Fe-MOF was utilized for the adsorption and localized Fenton-like degradation of p-nitroaniline (PNA). Importantly, the Fe centers exhibited a ternary role of (i) transforming MIL-101 into MIL-53lt morphology, (ii) boosting PNA adsorption on the MIL(Cr) material, and (iii) enabling the Fenton-like decomposition of the adsorbed PNA in reduced solution volume. Cr:Fe(50:50) exhibited the highest adsorption capacity of 378.9 mg/g, notwithstanding its smaller surface area (SBET = 8.9 m2/g). Overall, adsorption kinetics and isotherms correlated better with pseudo-second-order and Langmuir models, respectively. The adsorption mechanism was attributed to breathing effect, H-bonding and π-π interaction. Besides, PNA degradation kinetics stood at 0.21 min−1, and the reactive oxygen species were identified as •OH, •O2– and 1O2. During continuous removal of PNA, the Cr:Fe(50:50) MOF immobilized onto cotton met the environmental discharge standard (1 mg/L) up to 52 bed volumes (initial P = 10.0 mg/L at 1 mL/min). This study not only presents a superior polymorphic MOF adsorbent but also promotes the fabrication of localized Fenton-like catalysts for the removal of organic contaminants in wastewater.

Retrospective Study on Optimizing Breast Augmentation Outcomes in Transgender Patients: A Comprehensive Analysis of Tumescent Local Anesthesia Technique

BackgroundTumescent local anesthesia (TLA) involves the infusion of a saline solution containing lidocaine and epinephrine into tissues to achieve localized anesthesia and vasoconstriction. While the use of TLA in sub-glandular augmentation mammoplasty has been documented, we present a modified TLA approach for primary sub-muscular breast augmentation in transgender patients based on our experience over the past years.MethodsBetween the years 2014 and 2021, we performed primary sub-muscular breast augmentation on 20 transgender patients under TLA and conscious sedation. The tumescent solution consisted of 25 mL of 2% lidocaine, 8 mEq of sodium bicarbonate, and 1 mL of epinephrine (1 mg/1 mL) in 1000 mL of 0.9% saline solution. Initially, the solution was infiltrated between the pectoral fascia and the mammary gland, and subsequently, during the surgery, under the pectoralis major muscle.ResultsThe average volume of tumescent solution infiltrated during TLA was 740 mL per breast. There were no reports of adrenaline or lidocaine toxicity, and no cases required a conversion to general anesthesia. Patients experienced no pain or discomfort during the preoperative infiltration or surgical procedure.Reoperations due to short-term complications never occurred. We observed a major complication rate of 5%, represented by 1 hematoma. Long-term complications comprised one case of implant dislocation and one occurrence of dystrophic scar formation. No cases of capsular contracture needing reoperation, asymmetry, and implant rupture occurred. In total, one individual (5%) requested larger implants. Follow-up time ranged from 30 days to 1 years.ConclusionsOverall, augmentation mammaplasty is a valuable choice for transgender women aiming to enhance their feminine characteristics and alleviate gender dysphoria. It is imperative for patients to conduct thorough research, grasp the potential pros and cons, and consult experienced healthcare professionals in transgender care. Additionally, tumescent local anesthesia (TLA) has proven to be a safe and efficient method for sub-muscular breast augmentation, providing effective pain control with minimal postoperative complications, resulting in high patient satisfaction.Level of Evidence IVThis journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

An Efficient Method for Solving Problems of Acoustic Scattering on Three-Dimensional Transparent Structures

The article contains a study of methods for solving integral equations in the context of acoustic problems. The methodology considered is applied to describe acoustic wave propagation and scattering. Efficient discretization methods are used together with iterative methods to solve the operator equations, including an apparatus for fast multiplication of the resulting post-discretization Toeplitz matrices by a vector using the fast Fourier transform. The theoretical analysis of the proposed numerical algorithm demonstrates its efficiency in terms of the required number of arithmetic operations and the memory footprint of the computing system. The presented numerical simulation demonstrates the possibility of solving the problem of acoustic wave propagation in transparent media using the proposed methods. A visualization of the obtained solutions for a practical problem with a high level of discretization of the solution volume domain is also presented.

Oral Sulfate Solution Versus Polyethylene Glycol Solution for Bowel Preparation for Colonoscopy: A Randomised Controlled Trial in a Tertiary Care Centre

Colonoscopy is an indispensable procedure in the armamentarium of an endoscopist to diagnose the pathologies of the distal gastrointestinal tract. A well-prepared bowel is mandatory for an ideal colonoscopy which facilitates in clinching the diagnosis. The aim of the study was to compare the palatability, tolerance, volume and side effects of PEG solution as well as OSS for bowel preparation and also to assess the quality of bowel preparation using Boston Bowel Preparation Scale (BBPS) by the colonoscopist in a controlled, randomised, and double- blinded manner.

Improvement of survivability and developmental ability in vitrified rat oocytes

Oocyte cryopreservation is useful for human fertility treatment and strain preservation in both experimental and domestic animals. However, the embryonic development of vitrified rat oocytes was lower than that of vitrified embryos. To increase the viability of vitrified oocytes, intracellular ice formation during cooling and warming must be prevented. Rapid warming is important to prevent ice formation. Furthermore, suppressing the spontaneous activation of oocytes is also important because vitrification promotes the spontaneous activation of rat oocytes, and thus compromise developmental competence of the gametes. MG132, a proteasome inhibitor, suppresses the spontaneous activation of rat oocytes. Here, we examined the effects of rapid warming and MG132 treatment on the survival and embryonic development of vitrified rat oocytes. The warming rate was adjusted by changing the vitrification solution volume and warming solution temperature. The survival rate of oocytes vitrified in 10 μL solution and warmed at 50 °C (94%) was significantly higher than that of oocytes vitrified in 100 μL and 10 μL solution and warmed at 37 °C (49% and 81%, respectively). Furthermore, the rate of embryonic development of vitrified oocytes treated with MG132 during vitrification, warming, and intracytoplasmic sperm injection (ICSI) (44%) was significantly higher than that of untreated gametes (10%). Offspring were obtained after transferring embryos derived from MG132-treated vitrified oocytes (14%). Altogether, the survivability of vitrified rat oocytes increased by rapid warming, and MG132 improved embryonic development after ICSI.

Translating evidence: pain treatment in newborns, infants, and toddlers during needle-related procedures : German version

Treatment of pain in preterm, sick, and healthy newborns and infants and toddlers (up to 2years of age) is consistently reported to be inadequate, and effective strategies are poorly implemented. To present existing evidence of effective pain treatment strategies during needle-related procedures and to highlight initiatives focused on translating evidence into practice. This Clinical Update focuses on the 2022 International Association for the Study of Pain Global Year for Translating Pain Knowledge to Practice in the specific population of newborns, infants, and toddlers. Best evidence is reviewed, and existing knowledge translation strategies and programs available to implement evidence into practice are presented. Effective strategies for newborn and young infants during frequently occurring needle procedures include small volumes of sweet solutions, breastfeeding, or skin-to-skin care when feasible and culturally acceptable. In addition, strategies such as nonnutritive sucking, positioning, swaddling, gentle touch, facilitated tucking, and secure holding can be used. For toddlers, the evidence is less robust, and discerning between pain and distress is challenging. However, strategies recommended for needlerelated procedures include upright secure comfort holding by parents/caregivers, age-appropriate distraction, and topical anesthetics. Translation of effective pain management needs to involve the family, who need to be supported and empowered to comfort their child during painful procedures. Organizational, nationwide, and global initiatives aimed at improving implementation of effective pain treatments exist. There is evidence of effective pain management strategies for newborns, infants, and toddlers, and agreat deal of effort is being made to translate knowledge into action.

Facile fabrication of high thickness hydrophilic polymer brushes via Surface-Initiated Microliter-Scale copper mediated PhotoATRP toward antifouling surfaces

The recent development of sustainable chemistry motivates scientists to develop economically favourable, highly efficient, and environmentally friendly polymerization techniques. This contribution demonstrates a facile fabrication of hydrophilic polymer brushes via surface-initiated photochemically induced atom transfer radical polymerization using a copper catalyst in low concentrations and microlitre volume of polymerization mixture (SI-μL-CuPhotoATRP). The fabrication proceeds by sandwiching of μL reaction solution between a Si-wafer modified with ATRP-initiator and a glass slide under atmospheric and ambient conditions. Optimization of reaction conditions was realized on hydrophilic monomer such as 2-hydroxyethyl methacrylate (HEMA). Effect of various experimental parameters such as light intensity, solvents, ligands, the volume of the reaction solution, size of the Si-wafers, amount of CuBr2, and CuBr2/ligand ratio in kinetics, linear increase of polymer layer thickness, final thickness and profile of unmodified edges were investigated. The successful fabrication of hydrophilic polymer brushes is confirmed via Fourier transfer infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), profilometry and water contact angle. A linear thickness increase with time up to at least 300 nm was achieved, compared to polymethacrylate layers with thickness up to approximately 100 nm previously published by using photoATRP. The general applicability of the optimized conditions for SI-μL-CuPhotoATRP was further proved for two additional hydrophilic monomers, such as glycidyl methacrylate and 2-hydroxypropyl methacrylate. Furthermore, sequential homo and block copolymerization demonstrated the living character of fabrication conditions, permitting facile fabrication of well-controlled tetra block homo/copolymer brushes with a pyramid-like pattern on Si-wafer. Poly(2-hydroxyethyl methacrylate) (PHEMA) brushes-grown surfaces exhibit excellent antifouling properties and long-term structural stability. The facile, affordable, and environmentally friendly SI-μL-CuPhotoATRPapproachprovides avenues for various surface modifications, such as biomedical, soft robotic, and coating applications.

Does lung procurement and exposure to Perfadex impact heart transplantation outcomes.

Some studies have shown increased incidence of Primary Graft Dysfunction (PGD) after heart and lung procurement for heart transplant recipients. There have been limited investigations of the impact of lung procurement on heart procurement and the potential effects of the exposure to the type of lung preservation solution, the volume of the lung preservation solution and adequacy of decompression of the heart during heart and lung procurement and the impact on heart transplant outcomes. Adult heart transplant recipients in the UNOS database recorded from January 1, 2000 to June 30, 2022 formed the study cohort. Any heart that was procured with a lung team that utilized Perfadex preservation solution (XVIVO, Gothenburg, Sweden) was classified as exposed to Perfadex and otherwise classified as not exposed to Perfadex. Lung procurements performed with a preservation solution other than Perfadex or unknown were excluded (n=2486). Simple comparisons were made with t-tests or chi-squared tests. Logistic regression models were used to predict 30 day and 1 year survival. Accelerated failure time models were employed to analyze time to death and time to rejection. The cohort consisted of 34192 heart transplants, of which 21928 donors were not exposed to Perfadex (64.1%). There were statistically, but not clinically, significant differences in donor characteristics for these groups including in donor age (33.34±11.01 not exposed vs. 30.70±10.69 exposed; p<.001), diabetic donor (4% not exposed vs. 3% exposed; p=.004), and ischemic time (3.28±1.09h not exposed vs. 3.24±1.05h exposed; p=.002). In adjusted models, for all included donors, Perfadex exposure was associated with increased short term mortality, but no long term difference (1 year mortality OR 1.10, p=.014). Perfadex exposure was associated with increased short-term mortality for heart transplant recipients. Mechanistic investigation is warranted.

Contributory roles of concentration and pH in CaCO3 growth inhibition for submicron particles synthesis with additive Ca2+

Excessive growth of CaCO3 precipitates is inhibited by additive Ca2+. Here, we report the influence of concentration and solution pH on the extent of growth inhibition. Equal volumes of equimolar CaCl2 and Na2CO3 solutions were mixed and continuously dispersed in Ca(OH)2 solution, where Ca2+ irreversibly adsorb on the precipitates. Compared to conditions where additive Ca2+ are absent, this method can produce more than 90% decrease in particle size. We observe the degree of growth inhibition increases as the concentration of additive Ca2+, relative to the volume of precipitates, increases. An unusual role of pH is also revealed: growth inhibition that leads to the synthesis of monodisperse submicron CaCO3 particles is only observed in high alkaline pH conditions. Additive Ca2+ adsorb on CaCO3 precipitates in pH conditions above the isoelectric point (pH ≈ 9), but their ability to limit CaCO3 growth diminishes when pH < 12.

Heterogeneous ice nucleation of salt solution in porous media.

Water ubiquitously exists with dissolved salt in both natural and engineered porous media, such as soil, rock, concrete, and tissue; therefore, its freezing temperature depression behavior is of particular interest to various scientific communities tackling with mechanics and physics of porous media. To date, it remains elusive which physical mechanism accounts for its freezing temperature depression and how dissolved ions affect it. Herein, a series of pore-scale experiments were designated to investigate the freezing temperature of salt solutions in tubes with varying pore diameters, pore solution volumes, solid-liquid interfacial areas, ion concentrations, and ion types. The results reveal two main findings: (i) the freezing temperature depression of pore solutions is governed by the heterogeneous ice nucleation (HIN) at the water-solid interface, as evidenced by the observation that the freezing temperature decreases with the decreasing solid-liquid interfacial areas, regardless of pore diameter and pore solution volume; (ii) the dissolved salts alter HIN processes via changing the osmotic potential across the ice embryo-liquid water interface, as indicated by the observation that the freezing temperature is mainly determined by the salt concentration irrespective of salt types. Furthermore, the classical nucleation theory model is adapted for the freezing behavior of pore solutions by including an osmotic potential term. The model shows excellent performance in capturing experimental data with various pore solution concentrations, further substantiating the HIN as the physical mechanism governing pore solution freezing.