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1.
Artigo em Inglês | MEDLINE | ID: mdl-38647175

RESUMO

Efficient separation of Kr from Kr/Xe mixtures is pivotal in nuclear waste management and dark matter research. Thus far, scientists have encountered a formidable challenge: the absence of a material with the ability to selectively adsorb Kr over Xe at room temperature. This study presents a groundbreaking transformation of the renowned metal-organic framework (MOF) CuBTC, previously acknowledged for its Xe adsorption affinity, into an unparalleled Kr-selective adsorbent. This achievement stems from an innovative densification approach involving systematic compression of the MOF, where the crystal size, interparticle interaction, defects, and evacuation conditions are synergistically modulated. The resultant densified CuBTC phase exhibits exceptional mechanical resilience, radiation tolerance, and notably an unprecedented selectivity for Kr over Xe at room temperature. Simulation and experimental kinetic diffusion studies confirm reduced gas diffusion in the densified MOF, attributed to its small pore window and minimal interparticle voids. The lighter Kr element demonstrates facile surface passage and higher diffusivity within the material, while the heavier Xe encounters increased difficulty entering the material and lower diffusivity. This Kr-selective MOF not only represents a significant breakthrough in Kr separation but also demonstrates remarkable processability and scalability to kilogram levels. The findings presented herein underscore the transformative potential of engineered MOFs in addressing complex challenges, heralding a new era of Kr separation technologies.

2.
J Am Chem Soc ; 146(6): 4153-4161, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38300827

RESUMO

Separating ethane (C2H6) from ethylene (C2H4) is an essential and energy-intensive process in the chemical industry. Here, we report two flexible diamondoid coordination networks, X-dia-1-Ni and X-dia-1-Ni0.89Co0.11, that exhibit gate-opening between narrow-pore (NP) and large-pore (LP) phases for C2H6, but not for C2H4. X-dia-1-Ni0.89Co0.11 thereby exhibited a type F-IV isotherm at 273 K with no C2H6 uptake and a high uptake (111 cm3 g-1, 1 atm) for the NP and LP phases, respectively. Conversely, the LP phase exhibited a low uptake of C2H4 (12.2 cm3 g-1). This C2H6/C2H4 uptake ratio of 9.1 for X-dia-1-Ni0.89Co0.11 far surpassed those of previously reported physisorbents, many of which are C2H4-selective. In situ variable-pressure X-ray diffraction and modeling studies provided insight into the abrupt C2H6-induced structural NP to LP transformation. The promise of pure gas isotherms and, more generally, flexible coordination networks for gas separations was validated by dynamic breakthrough studies, which afforded high-purity (99.9%) C2H4 in one step.

3.
Nat Commun ; 15(1): 804, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280865

RESUMO

Purification of ethylene (C2H4) as the most extensive and output chemical, from complex multi-components is of great significance but highly challenging. Herein we demonstrate that precise pore structure tuning by controlling the network hydrogen bonds in two highly-related porous coordination networks can shift the efficient C2H4 separation function from C2H2/C2H4/C2H6 ternary mixture to CO2/C2H2/C2H4/C2H6 quaternary mixture system. Single-crystal X-ray diffraction revealed that the different amino groups on the triazolate ligands resulted in the change of the hydrogen bonding in the host network, which led to changes in the pore shape and pore chemistry. Gas adsorption isotherms, adsorption kinetics and gas-loaded crystal structure analysis indicated that the coordination network Zn-fa-atz (2) weakened the affinity for three C2 hydrocarbons synchronously including C2H4 but enhanced the CO2 adsorption due to the optimized CO2-host interaction and the faster CO2 diffusion, leading to effective C2H4 production from the CO2/C2H2/C2H4/C2H6 mixture in one step based on the experimental and simulated breakthrough data. Moreover, it can be shaped into spherical pellets with maintained porosity and separation performance.

4.
Pain Manag ; 13(8): 473-496, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37650756

RESUMO

A 2019 review article modified the socio-ecological model to contextualize pain disparities among different ethnoracial groups; however, the broad scope of this 2019 review necessitates deeper socio-ecological inspection of pain within each ethnoracial group. In this narrative review, we expanded upon this 2019 article by adopting inclusion criteria that would capture a more nuanced spectrum of socio-ecological findings on chronic pain within the Black community. Our search yielded a large, rich body of literature composed of 174 articles that shed further socio-ecological light on how chronic pain within the Black community is influenced by implicit bias among providers, psychological and physical comorbidities, experiences of societal and institutional racism and biomedical distrust, and the interplay among these factors. Moving forward, research and public-policy development must carefully take into account these socio-ecological factors before scaling up pre-existing solutions with questionable benefit for the chronic pain needs of Black individuals.


Assuntos
Dor Crônica , Humanos , População Branca , Negro ou Afro-Americano
5.
Dalton Trans ; 52(42): 15338-15342, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37395109

RESUMO

A metal-organic framework, SDMOF-1, with rigid pores of about 3.4 Å, which is appropriate for accommodating C2H2 molecules, exhibits high C2H2 adsorption capacity and great separation capability of the C2H2/C2H4 mixture. This work provides a new method to design aliphatic MOFs with a molecular sieving effect to realize efficient gas separation.

6.
Angew Chem Int Ed Engl ; 62(32): e202305390, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37261869

RESUMO

Adsorption-based removal of carbon dioxide (CO2 ) from gas mixtures has demonstrated great potential for solving energy security and environmental sustainability challenges. However, due to similar physicochemical properties between CO2 and other gases as well as the co-adsorption behavior, the selectivity of CO2 is severely limited in currently reported CO2 -selective sorbents. To address the challenge, we create a bioinspired design strategy and report a robust, microporous metal-organic framework (MOF) with unprecedented [Mn86 ] nanocages. Attributed to the existence of unique enzyme-like confined pockets, strong coordination interactions and dipole-dipole interactions are generated for CO2 molecules, resulting in only CO2 molecules fitting in the pocket while other gas molecules are prohibited. Thus, this MOF can selectively remove CO2 from various gas mixtures and show record-high selectivities of CO2 /CH4 and CO2 /N2 mixtures. Highly efficient CO2 /C2 H2 , CO2 /CH4 , and CO2 /N2 separations are achieved, as verified by experimental breakthrough tests. This work paves a new avenue for the fabrication of adsorbents with high CO2 selectivity and provides important guidance for designing highly effective adsorbents for gas separation.

7.
J Couns Psychol ; 70(5): 451-463, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37199952

RESUMO

Indigenous Canadians suffer disproportionately from mental health concerns tied to histories of colonization, including exposure to Indian Residential Schools. Previous research has indicated that preferred therapies for Indigenous populations fuse traditional cultural practices with mainstream treatment. The present study comprised 32 interviews conducted with Indigenous administrators, staff, and clients at a reserve-based addiction treatment center to identify community-driven and practical therapeutic solutions for remedying histories of coercive colonial assimilation. Thematic analysis of semi-structured interviews revealed that counselors tailored therapy through cultural preferences, including the use of nonverbal expression, culturally appropriate guidance, and alternative delivery formats. Additionally, they augmented mainstream therapeutic activities with Indigenous practices, including the integration of Indigenous concepts, traditional practices, and ceremonial activities. Collectively, this integration of familiar counseling approaches and Indigenous cultural practices in response to community priorities resulted in an innovative instance of therapeutic fusion that may be instructive for cultural adaptation efforts in mental health treatment for Indigenous populations and beyond. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Aconselhamento , Assistência à Saúde Culturalmente Competente , Serviços de Saúde do Indígena , Canadenses Indígenas , Saúde Mental , Humanos , Canadá , Saúde Mental/etnologia , Instituições Acadêmicas , Assistência à Saúde Culturalmente Competente/etnologia , Assistência à Saúde Culturalmente Competente/métodos
8.
Sci Rep ; 13(1): 6110, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37059715

RESUMO

Dolosigranulum pigrum-a lactic acid bacterium that is increasingly recognized as an important member of the nasal microbiome. Currently, there are limited rapid and low-cost options for confirming D. pigrum isolates and detecting D. pigrum in clinical specimens. Here we describe the design and validation of a novel PCR assay targeting D. pigrum that is both sensitive and specific. We designed a PCR assay targeting murJ, a single-copy core species gene identified through the analysis of 21 D. pigrum whole genome sequences. The assay achieved 100% sensitivity and 100% specificity against D. pigrum and diverse bacterial isolates and an overall 91.1% sensitivity and 100% specificity using nasal swabs, detecting D. pigrum at a threshold of 1.0 × 104 D. pigrum 16S rRNA gene copies per swab. This assay adds a reliable and rapid D. pigrum detection tool to the microbiome researcher toolkit investigating the role of generalist and specialist bacteria in the nasal environment.


Assuntos
Infecções por Bactérias Gram-Positivas , Cocos Gram-Positivos , Humanos , RNA Ribossômico 16S/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Reação em Cadeia da Polimerase , Primers do DNA , DNA Bacteriano
9.
J Community Psychol ; 51(7): 2618-2634, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36976752

RESUMO

This study explores behavioral health services for American Indians and Alaska Natives (AIANs) at six Urban Indian Health Programs (UIHPs). Interviews and focus groups with clinicians and staff inquired about behavioral health treatment available, service needs, client population, and financial and staffing challenges. Resulting site profiles were created based on focused coding and integrative memoing of site visit field notes and respondent transcripts. These six UIHPs evidenced diversity across multiple facets of service delivery even as they were united in their missions to provide accessible and effective behavioral health treatment to urban AIAN clients. Primary challenges to service provision included heterogenous client populations, low insurance coverage, limited provider knowledge, lack of resources, and incorporation of traditional healing. Collaborative research with UIHPs harbors the potential to recognize challenges, identify solutions, and share best practices across this crucial network of health care sites for improving urban AIAN well-being.


Assuntos
Indígena Americano ou Nativo do Alasca , Serviços de Saúde do Indígena , Serviços de Saúde Mental , Humanos , Acessibilidade aos Serviços de Saúde
10.
Intern Med J ; 53(11): 2042-2049, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36710434

RESUMO

BACKGROUND: Studies evaluating the economic burden of dermatological care in the transplant setting are currently not available in Australia. AIMS: To evaluate the clinical and economic burden of benign and malignant skin lesions in renal transplant recipients in Central Queensland. METHODS: A bottom-up approach was used to determine the clinical burden and direct costs from patient-level Medicare data obtained from Service Australia for skin lesions. RESULTS: Seventy-six percent of the renal transplant population in Central Queensland participated in this study. The median age was 57.0 years (standard deviation ± 13.6) and the majority (61.8%) of participants were men. The mean duration after transplant surgery was 99.9 months (interquartile range, 73.2-126.6 months). During a 2-year follow-up, 22 (40%) patients were diagnosed with benign skin lesions, 21 (38%) with nonmelanoma skin carcinoma (NMSC) and one (2%) with melanoma. There was a total of 231 visits to clinicians for diagnostic and therapeutic skin procedures and the direct costs to Medicare was $48 806 Australian Dollars (AUD) or $30 427 US Dollars (USD). Approximately 86% of the total direct costs was spent for nonNMSC and mean direct costs for NMSC was $763 AUD (or $476 USD). CONCLUSION: This Medicare data-based study provides further insight into the burgeoning clinical and economic burden of the care for benign and malignant skin lesions in the renal transplantation setting in Australia.


Assuntos
Carcinoma Basocelular , Carcinoma de Células Escamosas , Transplante de Rim , Neoplasias Cutâneas , Masculino , Humanos , Idoso , Feminino , Pessoa de Meia-Idade , Carcinoma Basocelular/epidemiologia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Estresse Financeiro , Austrália/epidemiologia , Fatores de Risco , Programas Nacionais de Saúde , Neoplasias Cutâneas/epidemiologia , Transplantados
11.
Angew Chem Int Ed Engl ; 62(8): e202217662, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36585907

RESUMO

Two C2 H6 -selective metal-organic framework (MOF) adsorbents with ultrahigh stability, high surface areas, and suitable pore size have been designed and synthesized for one-step separation of ethane/ethylene (C2 H6 /C2 H4 ) under humid conditions to produce polymer-grade pure C2 H4 . Experimental results reveal that these two MOFs not only adsorb a high amount of C2 H6 but also display good C2 H6 /C2 H4 selectivity verified by fixed bed column breakthrough experiments. Most importantly, the good water stability and hydrophobic pore environments make these two MOFs capable of efficiently separating C2 H6 /C2 H4 under humid conditions, exhibiting the benchmark performance among all reported adsorbents for separation of C2 H6 /C2 H4 under humid conditions. Moreover, the affinity sites and their static adsorption energies were successfully revealed by single crystal data and computation studies. Adsorbents described in this work can be used to address major chemical industrial challenges.

12.
Adv Mind Body Med ; 37(4): 12-19, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38466049

RESUMO

Compared to non-Hispanic White individuals, non-Hispanic Black Individuals report worse chronic pain from a variety of medical issues. Among the options for non-pharmacological pain treatment, mind-body interventions (MBI) are a promising modality to help Black individuals manage their chronic pain effectively. MBIs such as mindfulness meditation improve chronic pain and chronic pain-related outcomes by shifting the individual's perception of pain away from stress-related cognitive appraisals, emotional reactions, and behaviors. MBIs may also address disparities in chronic pain outcomes between Black and White individuals because of their contextual overlap with (1) centering and contemplative prayer, (2) racial empowerment, and (3) social support. Despite this overlap, the demand for MBIs among Black individuals has generally been low due to lingering access and acceptability barriers. To reduce these barriers for Black individuals with chronic pain, we must adopt a community-engaged approach and culturally adapt MBIs for the specific historic, environmental, financial, and psychosocial needs of Black individuals. Example adaptations include increasing Black representation among MBI instructors, reducing geographical access barriers, accommodating the financial and personal realities of Black adults, and explicitly allowing relevant attitudes, practices, and terms.


Assuntos
Dor Crônica , Adulto , Humanos , População Negra , Dor Crônica/terapia , Participação da Comunidade , Dissidências e Disputas , Participação dos Interessados , Brancos
13.
Inorg Chem ; 61(49): 19944-19950, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36455135

RESUMO

A gradual amide truncation strategy was presented to tune the pore chemistry and CO2 capture performance of a series of tetracarboxylate-based Cu-MOFs. These MOFs exhibited a high density of Lewis basic sites (LBSs) and open metal sites and were prepared with the goal to enhance CO2 selective adsorption capacity. [Cu2(L1)(H2O)2]n (NJU-Bai42: NJU-Bai for Nanjing University Bai's group), [Cu2(L2) (H2O)2]n (NJU-Bai17), and [Cu2(L3)(H2O)2]n (NTUniv-60: NTUniv for Nantong University) were synthesized, and we observed that the CO2 adsorption capacities and MOF structures were impacted by subtle changes in ligands. Interestingly, although the NTUniv-60 was decorated with the least LBSs in these three MOFs, its CO2 adsorption capacity reached 270 (53.0 wt %) and 164 (32.2 wt %) cm3 g-1 at 273 and 296 K under 1 bar, respectively, which is the highest data reported for MOFs under similar conditions. From the grand canonical Monte Carlo (GCMC) simulation, the cooperative interactions between the CO2 molecules within the shuttle-shaped cages of NTUniv-60 could potentially explain why the CO2 uptake is high in this material.


Assuntos
Dióxido de Carbono , Bases de Lewis , Humanos , Adsorção , Amidas , Transporte Biológico
14.
Kans J Med ; 15: 273-277, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36042840

RESUMO

Introduction: Colon cancer impacts the lives of Kansans and those across the United States. Epidermal growth factor receptor (EGFR) inhibitors, such as panitumumab and cetuximab, have gained popularity as first-line treatment for stage 4 colon cancer despite their toxicities and have been used by clinicians in later lines of therapy. EGFR inhibitors have been proven to be an efficacious first-line treatment for stage 4 colon cancer, but no study has investigated outcomes comparing EGFR inhibitors as first-line treatment to its use as second- or third-line treatment. This study investigated EGFR inhibitor therapy estimated overall survival when used as first-, second-, and third-line treatment for stage 4 colon cancer. Methods: A retrospective review was done for patients with stage 4 colon cancer who underwent EGFR inhibitor treatment at a large academic center from November 2007 to August 2021. The patients were stratified into five groups by the line in which they received the EGFR inhibitor treatment. A log-rank test was used to analyze the groups, and the median survival for each group was determined. Results: A total of 68 patients were reviewed; 18 received first-line, 23 received second-line, 18 received third-line, 6 received fourth-line, and 3 received sixth-line treatment with an EGFR inhibitor. Fourth- and sixth-line therapies were excluded due to small patient size. There was no significant difference in estimated survival time between any of the lines. Median survival of the therapies was found. Conclusions: There was no statistical difference in survival between the first-, second-, or third-line groups, which may provide justification for its use as a second- or third-line therapy.

16.
J Pain ; 23(10): 1697-1711, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35644442

RESUMO

Black communities are disproportionally affected by Chronic Musculoskeletal Pain (CMP), but little is known about the psychological predictors of CMP outcomes and their contextual determinants among Black individuals. To address this gap, we conducted a narrative review of extant literature to (1) report the major conceptual models mentioned in prior work explaining the link between contextual determinants and psychological responses to pain among Black individuals with CMP; and (2) describe psychological factors related to CMP outcomes in this population that are highlighted in the literature. We searched 4 databases (APA PsycNet, PubMed/MEDLINE, Scopus, and Google Scholar) using the following search terms: musculoskeletal pain, chronic pain, mental health, psychological, coping, health disparities, contextual factors, conceptual models, psychosocial, Black, African American, pain, disability, and outcomes. We illustrate 3 relevant conceptual models - socioecological, cumulative stress, and biopsychosocial - related to contextual determinants and several psychological factors that influence CMP outcomes among Black individuals: (1) disproportionate burden of mental health and psychiatric diagnoses, (2) distinct coping strategies, (3) pain-related perceived injustice and perceived racial/ethnic discrimination, and (4) preferences and expectations related to seeking and receiving pain care. The detailed clinical and research implications could serve as a blueprint for the providers and clinical researchers to address health disparities and improve care for Black individuals with CMP. PERSPECTIVE: This narrative review illustrates conceptual models explaining the link between contextual determinants and psychological responses to pain among Black individuals with chronic musculoskeletal pain. We discuss 3 relevant conceptual models - socioecological, cumulative stress, biopsychosocial -, and 4 psychological factors: disproportionate burden of mental health, distinct coping strategies, perceived injustice/discrimination, preferences/expectations.


Assuntos
Dor Crônica , Dor Musculoesquelética , Negro ou Afro-Americano/psicologia , Dor Crônica/psicologia , Monofosfato de Citidina , Etnicidade , Humanos , Dor Musculoesquelética/psicologia
18.
Transcult Psychiatry ; : 13634615221076706, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35200047

RESUMO

American Indians suffer from disproportionately high rates of mental health problems. Professional therapies may not meet the specific mental health needs of American Indians, owing to cultural mismatch and long histories of political disempowerment. Instead, Indigenous traditional spiritual practices are often promoted as alternative sources of health and help in these communities. In response to a community needs assessment, we developed a 12-week traditional spirituality curriculum in partnership with the urban American Indian health clinic in Detroit. Centered on the sweat lodge ceremony, the program was pilot tested with 10 community members. Semi-structured interviews were conducted with nine participants following the program. Based on our analyses, all participants endorsed responses within two overarching themes: impact on personal well-being, and suggestions for improvement reflecting their desire for an ongoing program. Participant responses about the program's impact comprised four themes: (1) improved psychological and spiritual well-being, (2) community benefit, (3) increase in cultural knowledge, and (4) a desire for further learning and sharing. Participant responses about their desire for an ongoing program also comprised four themes: (1) drop-in classes may be more practical as regular attendance was difficult for some, (2) future classes should include more areas of knowledge, (3) the program could be expanded to include more knowledge-holders and perspectives, and (4) the program should include a progression of classes to accommodate more diversity. Overall, participants reported benefit from participation in Indigenous spiritual practices; however, the program can be improved by further adapting the curriculum to the sometimes-challenging lives of its participants.

19.
ACS Appl Mater Interfaces ; 14(6): 8126-8136, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35119825

RESUMO

A combined experimental and theoretical study of H2 adsorption was carried out in Co-CUK-1 and Mg-CUK-1, two isostructural metal-organic frameworks (MOFs) that consist of M2+ ions (M = Co and Mg) coordinated to pyridine-2,4-dicarboxylate (pdc2-) and OH- ligands. These MOFs possess saturated metal centers in distorted octahedral environments and narrow pore sizes and display high chemical and thermal stability. Previous experimental studies revealed that Co-CUK-1 exhibits a H2 uptake of 183 cm3 g-1 at 77 K/1.0 atm [ Angew. Chem., Int. Ed. 2007, 46, 272-275, DOI: 10.1002/anie.200601627], while that for Mg-CUK-1 under the same conditions is 240 cm3 g-1 on the basis of the experimental measurements carried out herein. The theoretical H2 adsorption isotherms are in close agreement with the corresponding experimental measurements for simulations using electrostatic and polarizable potentials of the adsorbate. Through simulated annealing calculations, it was found that the primary binding site for H2 in both isostructural analogues is localized proximal to the center of the aromatic rings belonging to the pdc2- linkers. Inelastic neutron scattering (INS) spectroscopic studies of H2 adsorbed in both MOFs revealed a rotational tunnelling transition occurring at around 8 meV in the corresponding spectra; this peak represents H2 adsorbed at the primary binding site. Two-dimensional quantum rotation calculations for H2 localized at the primary and secondary binding sites in both MOFs yielded rotational energy levels that are in agreement with the transitions observed in the INS spectra. Even though both M-CUK-1 analogues possess different metal ions, they exhibit similar electrostatic environments, modeled structures at H2 saturation, and rotational potentials for H2 adsorbed at the most favorable adsorption site. Overall, this study demonstrates how important molecular-level details of the H2 adsorption mechanism inside MOF micropores can be derived from a combination of experimental measurements and theoretical calculations using two stable and isostructural MOFs with saturated metal centers and small pore windows as model systems.

20.
Angew Chem Int Ed Engl ; 61(11): e202117807, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35020976

RESUMO

The capture of the xenon and krypton from nuclear reprocessing off-gas is essential to the treatment of radioactive waste. Although various porous materials have been employed to capture Xe and Kr, the development of high-performance adsorbents capable of trapping Xe/Kr at very low partial pressure as in the nuclear reprocessing off-gas conditions remains challenging. Herein, we report a self-adjusting metal-organic framework based on multiple weak binding interactions to capture trace Xe and Kr from the nuclear reprocessing off-gas. The self-adjusting behavior of ATC-Cu and its mechanism have been visualized by the in-situ single-crystal X-ray diffraction studies and theoretical calculations. The self-adjusting behavior endows ATC-Cu unprecedented uptake capacities of 2.65 and 0.52 mmol g-1 for Xe and Kr respectively at 0.1 bar and 298 K, as well as the record Xe capture capability from the nuclear reprocessing off-gas. Our work not only provides a benchmark Xe adsorbent but proposes a new route to construct smart materials for efficient separations.

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