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Low-temperature single-crystal Raman spectra for RbM(III)(SO(4))(2).12H(2)O (M(III) = Al, Ga, In, Ti, V, Cr, Fe) and RbM(III)(SO(4))(2).12D(2)O (M(III) = Al, V) have been collected and assigned in the range 275-1200 cm(-)(1). These results permit classification of the Ti and V rubidium sulfate alums to the beta modification, whereas the remaining tervalent cations give the expected alpha modification. The dimorphism of the rubidium sulfate alums is explained in terms of the electronic structure of the tervalent cation, where the observation of the beta modification is associated with unequal occupancy of the t(2g) (O(h)()) orbitals. For the rubidium vanadium alums the (3)E(g) <-- (3)A(g) electronic Raman (eR) transition permits quantification of the trigonal field splitting of the t(2g) (O(h)()) orbitals (ca. 1940 cm(-)(1)). The profile of the eR band is sensitive both to changes in temperature and to deuteration. Analysis of the eR band profile suggests a reduced spin-orbit splitting of the (3)E(g) manifold, this being ascribed to excited state Jahn-Teller (J-T) effects. The similarity of the Raman spectra of the cesium and rubidium titanium sulfate alums suggest that they exhibit closely related structural chemistry, with both subject to phase transitions below 80 K. The observation that modes of E(g) symmetry are coupled to the structural change is consistent with the interpretation that the trigonal field leaves an orbital doublet ground term for titanium(III), leading to a cooperative J-T effect.
Variable-temperature single-crystal neutron diffraction structures of the alums CsM(III)(SO(4))(2).12D(2)O, where M(III) = Ti, V, Mn, and Ga, are reported. Structural differences are highlighted by the titanium and manganese alums, which undergo cubic (Pathremacr;) to orthorhombic (Pbca) phase transitions at approximately 13 and approximately 156 K, respectively. The structural instability exhibited by these salts is interpreted as arising from cooperative Jahn-Teller interactions, and these measurements characterize the structural changes that result from the coupling between the electronic and vibrational states. Although the symmetry changes associated with the phase transformations are analogous for the Ti and Mn alums, the low-temperature geometries of the tervalent hexaaqua cations are markedly different. Whereas the MnO(6) framework is subject to a pronounced tetragonal elongation, changes in the Ti-O bond lengths are very modest; but significant changes in the O-Ti-O bond angles and in the disposition of the coordinated water molecules are identified. The large differences in the transition temperatures and in the low-temperature stereochemistries of the [Ti(OD(2))(6)](3+) and [Mn(OD(2))(6)](3+) cations are related to the sensitivity of the energies of the t(2g) (O(h)) and e(g) (O(h)) orbitals to the various asymmetric vibrations of the hexaaqua complex.
The crystal structures at room (296 K) and low (173 K) temperature of several alpha-alums have been refined by single-crystal X-ray structure analysis. Many alpha-alums of known structure are disordered, the sulfate anions occupying one of two possible sites. All those studied here exhibited such disorder and the relative occupancies of the two sites are in excellent agreement with those obtained by Raman spectroscopy, where the nu1(SO4) mode is seen as a doublet owing to the presence of two different types of sulfate ion. No phase transitions were noted on cooling but there is less disorder.
Experiences obtained from recent improvements in the performance of solid-state (14)N MAS NMR spectroscopy have been used in a natural abundance (33)S MAS NMR investigation of the satellite transitions for this interesting spin I=3/2 isotope. This study reports the first observation of manifolds of spinning sidebands for these transitions in (33)S MAS NMR as observed for the two alums XAl(SO(4))(2) x 12H(2)O with X=NH(4) and K. For the NH(4)-alum a variable temperature (33)S MAS NMR study, employing the satellite transitions, shows that the (33)S quadrupole coupling constant (C(Q)) exhibits a linear temperature dependence (in the range -35 degrees C to 70 degrees C) with a temperature gradient of 3.1 kHz/ degrees C and undergoes a sign change with zero-crossing for C(Q) at 4 degrees C (277 K). For the isostructural K-alum a quite similar increase in the magnitude of C(Q) with increasing temperature is observed, and with a temperature gradient of 2.3 kHz/ degrees C. Finally, for optimization purposes, a study on the effect of the applied pulse widths at constant rf field strength on the intensity and variation in second-order quadrupolar lineshape for the central (1/2<-->-1/2) transition of the K-alum has been performed.
The mineral creedite is a fluorinated hydroxy hydrated sulphate of aluminium and calcium of formula Ca3Al2SO4(F,OH)·2H2O. The mineral has been studied by a combination of electron probe analysis to determine the molecular formula of the mineral and the structure assessed by vibrational spectroscopy. The spectroscopy of creedite may be compared with that of the alums. The Raman spectrum of creedite is characterised by an intense sharp band at 986 cm(-1) assigned to the SO4(2)- ν1 (Ag) symmetric stretching mode. Multiple bands of creedite in the antisymmetric stretching region support the concept of a reduction in symmetry of the sulphate anion. Multiple bands are also observed in the bending region with the three bands at 601, 629 and 663 cm(-1) assigned to the SO4(2)- ν4 (Ag) bending modes. The observation of multiple bands at 440, 457 and 483 cm(-1) attributed to the SO4(2)- ν2 (Bg) bending modes supports the concept that the symmetry of the sulphate is reduced by coordination to the water bonded to the Al(3+) in the creedite structure. The splitting of the ν2, ν3 and ν4 modes is attributed to the reduction of symmetry of the SO4 and it is proposed that the sulphate coordinates to water in the hydrated aluminium in bidentate chelation.
The reaction of an alkali metal aluminohydride MAlH4 (M = Li, Na) with N,N'-bis-(tert-butyl)sulfamide or N,N'-bis-(benzyl)sulfamide in THF produces the complex ions (Al[SO2(NR)2]2)- (R = tBu, Bn). The X-ray structures of [Li(THF)2(Al[SO2(NtBu)2]2)] infinity (1), [Na(15-crown-5)][Al(SO2(NtBu)2)2], (2) and ([Na(15-crown-5)][O2S(mu-NBn)2Al(mu-NBnSO2NBn)])2 (3.3THF) are reported. The two diazasulfate ligands [SO2(NtBu)2]2- are N,N' chelated to Al3+ in both 1 and 2. In the lithium derivative 1 the spirocyclic (Al[SO2(NtBu)2]2)- anions are bridged by the bis-solvated cations Li(THF)2+ to give a polymeric strand. In the sodium salt 2 the complex anion is O,O' chelated to Na+, which is further encapsulated by a 15-crown-5 ligand to give a monomeric ion-pair complex. By contrast, the benzyl derivative 3 forms a dimer in which the terminal [SO2(NBn)2]2- ligands are (N,N'),(O,O') bis-chelated to Al3+ and Na+, respectively, and the bridging ligands adopt a novel N,O-chelate, N'-monodentate bonding mode. The central core of 3 consists of two four-membered AlOSN rings bridged by two NtBu groups. Crystal data: 1, orthorhombic, Pna2(1), a = 20.159(5) degrees, b = 10.354(3) degrees, c = 15.833(4) degrees, alpha = beta = gamma = 90 degrees, V = 3304.7(15) A3, Z = 4; 2, monoclinic, P2(1)/n, a = 16.031(2) A, b = 9.907(2) A, c = 23.963(4) A, beta = 103.326(2) degrees, Z = 4; 3, triclinic, P1, a = 12.7237(11) A, b = 14.0108(13) A, c = 16.2050(14) A, alpha = 110.351(2) degrees, beta = 111.538(2) degrees, gamma = 97.350(2) degrees, Z = 1.
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Nowadays deodorants and antiperspirants play an important role in maintaining daily hygiene, exerting a substantial influence on both physical comfort and social functioning. Consequently, they can be regarded as a pivotal component of contemporary personal hygiene programs. The aim of this study was to undertake a comparative analysis of the elemental composition of diverse samples (72) of various roll-on deodorants and antiperspirants, sticks, and solid natural potassium-aluminium alums. These analyses were performed using ICP-OES and SEM-EDS techniques. The obtained results were then subjected to statistical and chemometric analysis. Studies demonstrated that Al and Zr were the most significant elements in the tested samples. Aluminium, a prevalent component in antiperspirants, was quantified in concentrations ranging from 0.9% to 4.4%, and in potassium-aluminium alums up to 4.7%. Aluminium and zirconium compounds were found to be the predominant elements in stick antiperspirants, with zirconium levels reaching up to 3%. The presence of lead was quantified in 35 of the 72 samples, with 19 samples exhibiting concentrations exceeding 1 mg/L. The highest lead level, reaching 15.90 mg/L, was found in potassium-aluminium alum. Furthermore, SEM-EDS analysis was conducted to verify the elemental composition, to provide data on additional ingredients, and to partially verify the information contained on the product labels.
Understanding how race and ethnicity affect health outcomes in patients with atopic dermatitis (AD) is crucial to optimizing patient-centered care and narrowing health disparities. Here, we aim to explore social drivers of health, treatment experiences, and healthcare professional (HCP) interactions in AD, stratified by patient race and ethnicity. This was a cross-sectional, non-interventional, web-based survey study, conducted from September 2023 to December 2023. Participants were recruited through the National Eczema Association and the AmeriSpeak panel. Adult US residents self-reporting a diagnosis of AD completed an electronic survey including questions on AD severity and stress over the last month, current AD treatment satisfaction, AD provider type, and perceptions of HCP interactions. Of 260 survey participants, 55.0% were White, 23.5% were Black/African American, 11.5% were Asian, and 10.0% ("Other") were American Indian/Alaskan Native, Native Hawaiian/Other Pacific Islander, or multiracial; 13.5% of participants were Hispanic/Latino; 43.1% of all participants rated their AD severity as moderate and 7.3% as severe; 37.7% reported being "quite a bit" or "very much" stressed by their AD. While most participants had health insurance and faced few issues procuring essential goods and services, Black/African American and Hispanic/Latino participants had higher uninsurance rates, were least often privately insured, and experienced more procurement issues than other groups; housing insecurity was high among "Other" participants. Most participants reported positive interactions with HCPs, but Black/African American participants most valued HCP cultural similarity, encountered it least often, and were likely to delay or not schedule appointments with culturally dissimilar HCPs. A fifth to a quarter of Black/African American, "Other," and Hispanic/Latino participants did not receive all needed healthcare services for AD, and nearly a third of all participants were dissatisfied with their treatment. Asian participants most frequently reported concerns about interactions with their HCPs, with only half trusting their HCP to effectively treat their AD. Race- and ethnicity-related heterogeneity in social drivers of health, treatment experiences, and HCP interactions among patients with AD emphasize the importance of including diverse patient populations in clinical research, highlight the importance of patient-physician concordance and/or HCP cultural sensitivity, and may help inform clinical practice considerations in AD management.
To demonstrate how students, alums and faculty view the effectiveness of the integration of university mission statements into curriculum and their significance for preparing for professional practice. This study builds on previous research exploring the influence of mission, vision and values statements in informing DNP program curricula and contributing to the development of students' professional identity by analyzing how the themes found were integrated into curricula and their perceived relevancy for practice. A mixed-methods approach was used called Group Concept Mapping, which built on the previous qualitative data found using quantitative analysis. A DNP program in the U.S. American Midwest participated in this research. Participants included thirty-one students, alumni and faculty from this DNP program. 32 statements were generated from the previous study, where participants completed a sorting and rating activity in the Group Wisdom software system. Next, the participants sorted these same statements into groups based on their perceived similarity and the results were analyzed using two bivariate statistical methods that created concept maps. Lastly, participants further identified how each statement was clearly articulated in their DNP educational experiences and how relevant these themes were for professional practice. The results suggest that the participants found most themes to be clearly articulated in the curriculum and found them relevant to practice. This study provides evidence that educational experiences that allow nurses to develop a professional identity are well-integrated into the DNP curriculum and that these themes have relevance to professional practice.
Literature exploring the medical profession through a generational lens is sparse. Every generation has unique priorities, values, and career expectations influencing their choices and behavior. The motives behind underlying differences and their impact on the career paths of medical graduates are not fully clear. This study explored generational differences in the career paths of medical graduates from the top academic medical school in Lebanon. A web-based survey, which included 38 questions, was sent to all 3866 physician alums of Lebanon's top academic medical school. The survey was designed to assess generational differences in career paths with respect to the following outcomes: contract type, specialty type, practice settings and work-life time allocation. Data was collected between November 2018 and January 2019, with up to three invite reminders. There were 403 respondents to the survey, with a response rate of 10.4%. Overall, 369 were included in the final analysis, 114 (36.7%) Boomers [born 1946-1964], 137 (34.0%) Generation Xers [Born 1965-1980] and 118 (29.3%) Millennials [Born 1981-1996]. Findings show that the percentage of women increased with each generation (Boomers: 17.5%; Generation Xers: 39.4%; Millennials: 45.8%, p < 0.001). Across generations, marriage (Boomers: 87.7%; Generation Xers: 83.9%; Millennials: 35.6%, p < 0.001) and having kids (Boomers: 90.4%; Generation Xers: 81.0%; Millennials: 20.3%; p < 0.001) dropped whereas full-time contracts (Boomers: 81.5%; Generation Xers: 86.0%; Millennials: 93.9%, p = 0.019) and spouse employment increased (Boomers: 48.0%; Generation Xers: 68.7%; Millennials: 72.3%, p = 0.002). The odds of being full-time in Generation Xers (OR = 1.16, 95% CI [0.50; 2.72], p = 0.73) and Millennials (OR = 2.22, 95% CI [0.60; 8.20], p = 0.23) were not significantly higher than Boomers. Younger generations opted less for surgical specialties compared to Boomers, be it Generation Xers (OR = 0.44, 95% CI [0.21; 0.92], p = 0.029) or Millennials (OR = 0.56, 95% CI [0.17; 1.90], p = 0.35). Generation Xers and Millennials were likelier to work in academic medical centers than Boomers. Compared to working in academic medical centers, the odds of working in private practice (Generation Xers: OR = 0.75, 95% CI [0.40; 1.42], p = 0.375; Millennials: OR = 0.35, 95% CI [0.12; 0.98], p = 0.046) or other settings (Generation Xers: OR = 0.49, p = 0.149, 95% CI [0.18, 1.29]; Millennials: OR = 0.46, 95% CI [0.11; 1.19], p = 0.285) were lower. Physicians across generations spent similar hours on professional work. Among work-related activities, time spent on research activities increased across generations (Boomers: 6.38 h/week; Generation Xers: 6.76 h/week; Millennials: 13.39 h/week, p = 0.001). Being a Generation Xer significantly increased the personal time spent on total domestic work by (0.190 h/week, p = 0.012) compared to being a Boomer; being a Millennial did not. Time allocated by physicians' spouses for household work decreased across generations (Boomers: 14.95 h/week; Generation Xers: 12.82 h/week; Millennials: 10.44 h/week, p < 0.001). These findings provide empirical evidence documenting changes in career paths and work-life balance across generations in the medical field while also highlighting interesting trends. Further research is needed for additional insight into these generational differences.
As an educational aid, the Korean government has developed and funded a graduate-level global information telecommunications technology program (ITTP) for ICT officers in developing countries. Questions have arisen about whether the program can achieve its goals and obtain mutual benefits between Korea and participating nations. Using a total quality management (TQM) framework as a unique case analysis, we evaluated ITTP's resources and performance from 2006 to 2014. Our results show that ITTP has focused on the quantitative promotion of students and alums from various countries and their learning of Korea-centric ICT, policies, and culture. In particular, the Korean government's lax evaluation of ITTP performance has led to weak responsibility, ambiguous task identity, missed opportunities for self-improvement, and low participation among students and stakeholders. These findings highlight the need for graduate programs and their stakeholders to reinforce internal and external evaluations of the program's performance and provide feedback for reciprocal development.
Aluminum adjuvants (Alum), approved by the US Food and Drug Administration, have been extensively used in vaccines containing recombinant antigens, subunits of pathogens, or toxins for almost a century. While Alums typically elicit strong humoral immune responses, their ability to induce cellular and mucosal immunity is limited. As an alternative, layered double hydroxide (LDH), a widely used antacid, has emerged as a novel class of potent nano-aluminum adjuvants (NanoAlum), demonstrating advantageous physicochemical properties, biocompatibility and adjuvanticity in both humoral and cellular immune responses. In this review, we summarize and compare the advantages and disadvantages of Alum and NanoAlum in these properties and their performance as adjuvants. Moreover, we propose the key features for ideal adjuvants and demonstrate that LDH NanoAlum is a promising candidate by summarizing its current progress in immunotherapeutic cancer treatments. Finally, we conclude the review by offering our integrated perspectives about the remaining challenges and future directions for NanoAlum's application in preclinical/clinical settings.
Ever since the development of the first vaccine, vaccination has had the great impact on global health, leading to the decrease in the burden of numerous infectious diseases. However, there is a constant need to improve existing vaccines and develop new vaccination strategies and vaccine platforms that induce a broader immune response compared to traditional vaccines. Modern vaccines tend to rely on certain nanotechnology platforms but are still expected to be readily available and easy for large-scale manufacturing and to induce a durable immune response. In this review, we present an overview of the most promising nanoadjuvants and nanoparticulate delivery systems and discuss their benefits from tehchnological and immunological standpoints as well as their objective drawbacks and possible side effects. The presented nano alums, silica and clay nanoparticles, nanoemulsions, adenoviral-vectored systems, adeno-associated viral vectors, vesicular stomatitis viral vectors, lentiviral vectors, virus-like particles (including bacteriophage-based ones) and virosomes indicate that vaccine developers can now choose different adjuvants and/or delivery systems as per the requirement, specific to combatting different infectious diseases.
Subunit vaccines have advantages of good safety, minimal reactogenicity, and high specificity. However, subunit vaccines also show a crucial disadvantage of poor immunogenicity and, therefore, are often formulated with an adjuvant carrier to form a vaccine adjuvant-delivery system (VADS) to enhance their efficacies. Alums, the coarse aggregates of the insoluble aluminum salts, are the conventional adjuvants and have been widely used in clinical vaccines for a long time. Unfortunately, alums also show two main drawbacks of low potency in eliciting cellular immunity, and high reactogenicity to cause unwanted inflammations. Therefore, herein the phospholipid bilayer-coated aluminum oxide nanoparticles (PLANs) and the PEGylated PLANs (PEG-PLANs) were engineered as a VADS to overcome the drawbacks of both subunit vaccines and coarse alums, while synergizing their functions. In vitro experiments demonstrated that, unlike the micron-sized alums, the nanosized PLANs and PEG-PLANs loaded with model antigen of ovalbumin (OVA) showed a high safety profile and were able to promote APC (antigen-presenting cell) uptake and engender lysosome escape for enhancing the MHC (major histocompatibility complex)-I-antigen display. Subcutaneously administered to mice, PLANs and, especially, PEG-PLANs smoothly trafficked into the draining lymph nodes, wherein the densely clustered immune cells were activated in substantial numbers, leading to robust immunoresponses and efficient production of the anti-antigen antibodies and CD8+ T cells. Thus, the aluminum-based nanocarriers, especially the PEG-PLANs, are a promising VADS possessing the potential of eliciting strong and comprehensive immunity against pathogens.
The formation and extraction of the ion-associates of the vanadium(V)-3,5-dinitrocatechol (DNC) anionic chelate complex with various basic dyes have been studied and a new sensitive extraction-spectrophotometric method for the determination of vanadium based on the system V(V)-DNC-Brilliant Green has been developed. Beer's law is obeyed up to a vanadium concentration of 0.3 mug/ml and the molar absorptivity is 1.7 x 1O(5) l.mole(-1). cm(-1) at 630 nm. The molar ratios of the components and the form of the vanadium(V) cation in the extracted compound have been determined, and the formula [VO(OH)(DNC)(2-)(2)][BG(+)](2) is proposed. Titanium, molybdenum, tungsten, EDTA and thiocyanate interfere seriously. The method becomes specific after a preliminary separation of vanadium by its extraction as the BPHA complex from H(2)SO(4)-HF medium, and is 40 times more sensitive than the spectrophotometric BPHA method. The proposed method has been applied to determination of traces of vanadium (about 10(-5)%) in alums.
Immunocompetent cells were studied in the stroma and epithelium of 34 cases of mammary gland dysplasia. The following stainings were used for light microscopy: hematoxylin and eosin, methods of Brachet, van Gieson, Romanovsky-Giemsa, hallocyanine alums, Gomori, PAS-reaction as well as the determination of acid and alkaline phosphatases, glucose-6-phosphate and succinate dehydrogenase were used. 14 cases were studied ultrastructurally. Two types of small B lymphocytes and one type of large lymphocytes, stromal macrophages are described. Their morphofunctional characteristics is given and their properties in proliferating and non-proliferating fibroadenomatosis are shown. Interaction of intraepithelial large granular lymphocytes (normal killers) with immature epithelial cells resulting in the death of these epitheliocytes is described. The results obtained are regarded as a morphological manifestation of the immune surveillance.