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1.
Clin Cancer Res ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38718141

RESUMO

PURPOSE: Treatment paradigms for Isocitrate dehydrogenase (IDH) mutant gliomas are rapidly evolving. While typically indolent and responsive to initial treatment, these tumors invariably recur at higher grade and require salvage treatment. Homozygous deletion of the tumor suppressor gene CDKN2A/B frequently emerges at recurrence in these tumors, driving poor patient outcome. We investigated the effect of CDK-Rb pathway blockade on IDH-mutant glioma growth in vitro and in vivo using CDK4/6 inhibitors (CDKi). EXPERIMENTAL DESIGN: Cell viability, proliferation assays and flow cytometry were used to examine the pharmacologic effect of two distinct CDKis, palbociclib and abemaciclib, in multiple patient-derived IDH-mutant glioma lines. Isogenic models were used to directly investigate the influence of CDKN2A/B status on CDKi sensitivity. Orthotopic xenograft tumor models were used to examine efficacy and tolerability of CDKi in vivo. RESULTS: CDKi treatment leads to decreased cell viability and proliferative capacity in patient-derived IDH-mutant glioma lines, coupled with enrichment of cells in G1 phase. CDKN2A inactivation sensitizes IDH-mutant glioma to CDKi in both endogenous and isogenic models with engineered CDKN2A deletion. CDK4/6 inhibitor administration improves survival in orthotopically implanted IDH-mutant glioma models. CONCLUSIONS: IDH-mutant gliomas with deletion of CDKN2A/B are sensitized to CDK4/6 inhibitors. These results support investigation of the use of these agents in a clinical setting.

2.
Front Public Health ; 12: 1344854, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38765489

RESUMO

Introduction: The oldest olds (aged 85 and over) are the fastest-growing age segment. However, our understanding of their mobility is limited. To address this gap, we invited 19 U.S. and 30 Chinese "oldest old" to take part in focus groups and complete a mobility questionnaire. We focus on travel mode choice, which includes changes in travel modes, frequency of usage, and perceptions of comfort. Methods: Older adults' familiarity and acceptance of new mobility technologies (e.g., ridesharing, carsharing, and autonomous vehicles) were measured by questionnaire and focus group. Word clouds were also used to illustrate people's reasons for choosing their primary mode of transportation. Results and discussion: The results show that both panels of older adults similarly feel some extent of travel limitations. But the responses among the two groups differ: 18 American participants chose "drive myself" as their primary option a decade ago, while 11 chose it now; no Chinese participants selected it either a decade ago or now. Both currently and 10 years ago, there was a significant difference in mode choice between participants in China and the United States. However, this gap has narrowed over the past decade. Participants in China have significantly changed their transportation preferences compared to 10 years ago, while participants in the US have remained nearly unchanged. American respondents consider "ease" as an important factor, while Chinese respondents pay more attention to "safety" and "no other option to get around" when making travel mode choices. Compared to Chinese participants, American participants were more comfortable with driving an autonomous vehicle. These differences may result from the various developmental stages and transportation policies of the two countries. This study supports the development of new mobility technologies for the oldest old to improve their quality of life.


Assuntos
Comportamento de Escolha , Grupos Focais , Meios de Transporte , Humanos , China , Estados Unidos , Masculino , Feminino , Inquéritos e Questionários , Idoso de 80 Anos ou mais , Viagem/psicologia , Condução de Veículo/psicologia
3.
Cancer Cell ; 42(5): 904-914.e9, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38579724

RESUMO

A subset of patients with IDH-mutant glioma respond to inhibitors of mutant IDH (IDHi), yet the molecular underpinnings of such responses are not understood. Here, we profiled by single-cell or single-nucleus RNA-sequencing three IDH-mutant oligodendrogliomas from patients who derived clinical benefit from IDHi. Importantly, the tissues were sampled on-drug, four weeks from treatment initiation. We further integrate our findings with analysis of single-cell and bulk transcriptomes from independent cohorts and experimental models. We find that IDHi treatment induces a robust differentiation toward the astrocytic lineage, accompanied by a depletion of stem-like cells and a reduction of cell proliferation. Furthermore, mutations in NOTCH1 are associated with decreased astrocytic differentiation and may limit the response to IDHi. Our study highlights the differentiating potential of IDHi on the cellular hierarchies that drive oligodendrogliomas and suggests a genetic modifier that may improve patient stratification.


Assuntos
Neoplasias Encefálicas , Diferenciação Celular , Isocitrato Desidrogenase , Mutação , Oligodendroglioma , Oligodendroglioma/genética , Oligodendroglioma/patologia , Oligodendroglioma/tratamento farmacológico , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/antagonistas & inibidores , Humanos , Diferenciação Celular/efeitos dos fármacos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/tratamento farmacológico , Linhagem da Célula/efeitos dos fármacos , Receptor Notch1/genética , Receptor Notch1/metabolismo , Proliferação de Células/efeitos dos fármacos , Animais , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Camundongos , Análise de Célula Única/métodos
5.
BMJ Open ; 14(4): e069236, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626980

RESUMO

OBJECTIVES: The study aims to investigate the perceptions of patients with thyroid cancer on the potential impact of diagnosis and treatment delays during the COVID-19 pandemic. DESIGN: This study involved qualitative semi-structured telephone interviews. The interviews were transcribed verbatim, analysed using the thematic framework analysis method and reported using the Consolidated Criteria for Reporting Qualitative Research. SETTING: Participants in the study were treated and/or managed at hospital sites across New South Wales and Victoria, Australia. PARTICIPANTS: 17 patients with thyroid cancer were interviewed and included in the analysis (14 females and 3 males). RESULTS: The delays experienced by patients ranged from <3 months to >12 months. The patients reported about delays to diagnostic tests, delays to surgery and radioactive iodine treatment, perceived disease progression and, for some, the financial burden of choosing to go through private treatment to minimise the delay. Most patients also reported not wanting to experience delays any longer than they did, due to unease and anxiety. CONCLUSIONS: This study highlights an increased psychological burden in patients with thyroid cancer who experienced delayed diagnosis and/or treatment during COVID-19. The impacts experienced by patients during this time may be similar in the case of other unexpected delays and highlight the need for regular clinical review during delays to diagnosis or treatment.


Assuntos
COVID-19 , Neoplasias da Glândula Tireoide , Masculino , Feminino , Humanos , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/terapia , Diagnóstico Tardio , Radioisótopos do Iodo , Pandemias , Vitória , Pesquisa Qualitativa , Teste para COVID-19
6.
Chemosphere ; 354: 141681, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38467199

RESUMO

Dimethylsilanediol (DMSD) is the common breakdown product of methylsiloxanes such as polydimethylsiloxane (PDMS) and volatile methylsiloxanes (VMS) in soil. In this work, we first present a sorbent selection experiment aiming to identify a sorbent that can trap gas-phase DMSD without causing DMSD condensation and VMS hydrolysis at environmentally relevant humidities. With a proper sorbent (Tenax) identified, the volatilization of DMSD from water and various wet soil and soil materials were measured in a controlled environment. It was demonstrated that DMSD underwent volatilization after soil water was completely evaporated. Various types of soil constituents show drastic differences in preventing DMSD from volatilization. Analysis of the sorbent-captured products provides further insight, most notably that virtually no cyclic methylsiloxanes are formed during the volatilization of DMSD from water or soil materials, except in one extreme case where only traces are detected.


Assuntos
Compostos de Organossilício , Solo , Água , Volatilização
7.
Resusc Plus ; 17: 100550, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38304635

RESUMO

Aim of the study: Survival to hospital discharge from out-of-hospital cardiac arrest (OHCA) after receiving treatment from emergency medical services (EMS) is less than 10% in the United States. Community-focused interventions improve survival rates, but there is limited information on how to gain support for new interventions or program activities within these populations. Using data from the RAndomized Cluster Evaluation of Cardiac ARrest Systems (RACE-CARS) trial, we aimed to identify the factors influencing emergency response agencies' support in implementing an OHCA intervention. Methods: North Carolina counties were stratified into high-performing or low-performing counties based on the county's cardiac arrest volume, percent of bystander-cardiopulmonary resuscitation (CPR) performed, patient survival to hospital discharge, cerebral performance in patients after cardiac arrest, and perceived engagement in the RACE-CARS project. We randomly selected 4 high-performing and 3 low-performing counties and conducted semi-structured qualitative interviews with emergency response stakeholders in each county. Results: From 10/2021 to 02/2022, we completed 29 interviews across the 7 counties (EMS (n = 9), telecommunications (n = 7), fire/first responders (n = 7), and hospital representatives (n = 6)). We identified three themes salient to community support for OHCA intervention: (1) initiating support at emergency response agencies; (2) obtaining support from emergency response agency staff (senior leadership and emergency response teams); and (3) and maintaining support. For each theme, we described similarities and differences by high- and low-performing county. Conclusions: We identified techniques for supporting effective engagement of emergency response agencies in community-based interventions for OHCA improving survival rates. This work may inform future programs and initiatives around implementation of community-based interventions for OHCA.

8.
Chemosphere ; 352: 141454, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38354863

RESUMO

Dimethylsilanediol (DMSD) is the degradation product of methylsiloxane polymers and oligomers such as volatile cyclic methylsiloxanes (cVMS). To better understand the environmental fate of this key degradation product, we conducted a three-part study on the movement of DMSD in soil. The objective of this third and final study was to determine the fate of DMSD in soil-plant systems under constant irrigation. Soil columns were constructed using two soils with the upper 20 cm layers spiked with 14C-labeled DMSD. Corn seedlings were transplanted into the soil columns and placed in a field plot underneath a transparent cover that prevented rainwater from reaching the soil columns while allowing soil water to be volatilized freely. The soil-plant columns were regularly irrigated with known amounts of DMSD-free plant growth solution to sustain the plant growth. At pre-determined time intervals (15-67 days), the plant and soil columns were sectioned and the distribution of 14Corganosilicon species in the soil profile and plant parts was determined using a combination of Liquid Scintillation Counting and High-Performance Liquid Chromatography-Flow Scintillation Analysis, while soil water loss was determined gravimetrically. It was found that the majority (>92 %) of DMSD initially spiked into the soil was removed from the soil-plant systems. Although DMSD was transported from the soil to the plant, it was subsequently volatilized from the plant via transpiration, with only a small fraction (∼5%) remaining at the conclusion of the experiments. In addition, little non-extractable DMSD was found in the top layer of soil in the soil-plant systems, suggesting that the air-drying of soil is a necessary pre-condition for the formation of such non-extractable silanol residue on topsoil.


Assuntos
Compostos de Organossilício , Poluentes do Solo , Poluentes Químicos da Água , Solo , Água , Poluentes Químicos da Água/análise , Poluentes do Solo/análise
9.
Chemosphere ; 352: 141478, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38364924

RESUMO

Dimethylsilanediol (DMSD) is a primary degradation product of silicone materials in the environment. Due to its low air/water partition coefficient and low soil/water distribution coefficient, this compound is not expected to undergo sorption and volatilization in wet soil. In an accompanying paper, we confirm that under controlled indoor conditions in test tubes, there is little to no volatilization of DMSD from soil and soil constituents if soil is wet. However, a significant amount of DMSD was volatilized when the soil substrates became air dried. Given the importance of water on the partition and fate of DMSD, we now report a continuation of this study focusing on the relation between DMSD removal and water loss in re-constituted soil columns under outdoor conditions. Consistent with predictions based on its partition properties and reconciling this evidence with previously reported field and laboratory studies, DMSD distribution was found to be largely dependent on water partitioning. The results suggested that DMSD moved upward in soil profile as soil water was evaporated from topmost layers with little DMSD retention by the soil matrix. As soil dried, a fraction of DMSD was sorbed by the soil matrix in the topmost layer, while most of the spiked radio-labeled DMSD was removed from soil through volatilization.


Assuntos
Compostos de Organossilício , Poluentes do Solo , Água/química , Solo , Silicones , Poluentes do Solo/análise
10.
Circ Cardiovasc Interv ; 17(3): e013003, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38410946

RESUMO

BACKGROUND: The American College of Cardiology Reduce the Risk: PCI Bleed Campaign was a hospital-based quality improvement campaign designed to reduce post-percutaneous coronary intervention (PCI) bleeding events. The aim of the campaign was to provide actionable evidence-based tools for participants to review, adapt, and adopt, depending upon hospital resources and engagement. METHODS: We used data from 8 757 737 procedures in the National Cardiovascular Data Registry between 2015 and 2021 to compare patient and hospital characteristics and bleeding outcomes among campaign participants (n=195 hospitals) and noncampaign participants (n=1384). Post-PCI bleeding risk was compared before and after campaign participation. Multivariable hierarchical logistic regression was used to determine the adjusted association between campaign participation and post-PCI bleeding events. Prespecified subgroups were examined. RESULTS: Campaign hospitals were more often higher volume teaching facilities located in urban or suburban locations. After adjustment, campaign participation was associated with a significant reduction in the rate of bleeding (bleeding: adjusted odds ratio, 0.61 [95% CI, 0.53-0.71]). Campaign hospitals had a greater decrease in bleeding events than noncampaign hospitals. In a subgroup analysis, the reduction in bleeding was noted in non-ST-segment-elevation acute coronary syndrome and ST-segment-elevation myocardial infarction patients, but no significant reduction was seen in patients without acute coronary syndrome. CONCLUSIONS: Participation in the American College of Cardiology Reduce the Risk: PCI Bleed Campaign was associated with a significant reduction in post-PCI bleeding. Our results underscore that national quality improvement efforts can be associated with a significant impact on PCI outcomes.


Assuntos
Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Humanos , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/terapia , Hemorragia/etiologia , Hemorragia/prevenção & controle , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Sistema de Registros , Fatores de Risco , Resultado do Tratamento , Estados Unidos
11.
Neurosurg Focus ; 56(2): E2, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38301244

RESUMO

OBJECTIVE: Several studies have compared the immune microenvironment of isocitrate dehydrogenase (IDH)-wildtype glioma versus IDH-mutant glioma. The authors sought to determine whether histological tumor progression in a subset of IDH-mutant glioma was associated with concomitant alterations in the intratumoral immune microenvironment. METHODS: The authors performed bulk RNA sequencing on paired and unpaired samples from patients with IDH-mutant glioma who underwent surgery for tumor progression across multiple timepoints. They compared patterns of differential gene expression, overall inflammatory signatures, and transcriptomic measures of relative immune cell proportions. RESULTS: A total of 55 unique IDH-mutant glioma samples were included in the analysis. The authors identified multiple genes associated with progression and higher grade across IDH-mutant oligodendrogliomas and astrocytomas. Compared with lower-grade paired samples, grade 4 IDH-mutant astrocytomas uniquely demonstrated upregulation of VEGFA in addition to counterproductive alterations in inflammatory score reflective of a more hostile immune microenvironment. CONCLUSIONS: Here, the authors have provided a transcriptomic analysis of a progression cohort for IDH-mutant glioma. Compared with lower-grade tumors, grade 4 astrocytomas displayed alterations that may inform the timing of antiangiogenic and immune-based therapy as these tumors progress.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Isocitrato Desidrogenase/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Regulação para Cima , Mutação/genética , Glioma/genética , Glioma/patologia , Astrocitoma/genética , Microambiente Tumoral/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Am Nat ; 203(1): 139-146, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38207139

RESUMO

AbstractThe coexistence of multiple reproductives in eusocial insects is widespread, yet the decisions leading to additional queen acceptance are not well understood. Unlike in vertebrates, acceptance decisions are likely controlled by the more numerous helper population rather than the parent reproductive. Yet there are likely to be queen-worker differences in acceptance criteria because workers and queens differ in their relatedness to a secondary queen. We develop a model that examines queen-worker conflict in two scenarios: accepting a queen's sister or daughter. We additionally ask how the mating frequency and split sex ratios affect the outcomes of these conflicts. Our results reveal that conflict over queen acceptance is highest in monandrous mating systems. We identify a "window of conflict" in which a queen is selected to accept her sister but her workers do not. Our result, that polyandry neutralizes conflict over acceptance thresholds, suggests that conflict suppression may be an additional contributor to the maintenance of polyandrous mating systems.


Assuntos
Insetos , Reprodução , Animais , Feminino , Humanos , Razão de Masculinidade
14.
J Magn Reson Open ; 16-172023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38046795

RESUMO

We report several inductively coupled RF coil designs that are very easy to construct, produce high signal-to-noise ratio (SNR) and high spatial resolution while accommodating life support, anesthesia and monitoring in small animals. Inductively coupled surface coils were designed for hyperpolarized 13 C MR spectroscopic imaging (MRSI) of mouse brain, with emphases on the simplicity of the circuit design, ease of use, whole-brain coverage, and high SNR. The simplest form was a resonant loop designed to crown the mouse head for a snug fit to achieve full coverage of the brain with high sensitivity when inductively coupled to a broadband pick-up coil. Here, we demonstrated the coil's performance in hyperpolarized 13 C MRSI of a normal mouse and a glioblastoma mouse model at 4.7 T. High SNR exceeding 70:1 was obtained in the brain with good spatial resolution (1.53 mm × 1.53 mm). Similar inductively coupled loop for other X-nuclei can be made very easily in a few minutes and achieve high performance, as demonstrated in 31 P spectroscopy. Similar design concept was expanded to splitable, inductively coupled volume coils for high-resolution proton MRI of marmoset at 3T and 9.4T, to easily accommodate head restraint, vital-sign monitoring, and anesthesia delivery.

15.
Am J Cardiol ; 207: 314-321, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774472

RESUMO

Our objective is to use computed tomography angiography (CTA) and computed tomography perfusion (CTP) to identify the ischemic significance of myocardial bridging (MB). We also seek to determine the long-term prognostication of MB in the presence or absence of obstructive coronary artery disease (CAD). The CORE320, a prospective, multicenter study including 381 patients with known or suspected CAD clinically referred for invasive coronary angiography who underwent combined (CTA-CTP) and single-photon emission computed tomography before conventional coronary angiography. The incidence of MB was identified in 135 patients (35.4%) with 93.9% identified in the left anterior descending artery. MB were divided as partially encased versus fully encased. There was no difference in ischemia identified between partially encased MB and fully encased MB (37 [40%] vs 25 [35%], p = 0.54]. Ischemia was identified at similar rates in partially versus fully encased MB by single-photon emission computed tomography at (8 [9%] vs 8 [11%], p = 0.57] and CTP (34 [37%] vs 21 [30%], p = 0.33]. There was no difference in the primary outcome of 5-year outcome of combined incidence of myocardial infarction or death. The restricted mean survival time in patients with CTA with <50% stenosis with or without a MB was 4.906 years (95% confidence interval 4.759 to 5.000) and 4.891 years (95% confidence interval 4.718 to 5.000), respectively (p = 0.824). Cardiac computed tomography perfusion imaging can assess both anatomic and functional significance of myocardial bridging with diagnostic accuracy similar to current standard imaging. Furthermore, 5-year cardiovascular events were not different with the presence of MB in both obstructive and non-obstructive CAD.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Ponte Miocárdica , Infarto do Miocárdio , Imagem de Perfusão do Miocárdio , Humanos , Angiografia por Tomografia Computadorizada , Estudos Prospectivos , Prognóstico , Seguimentos , Doença da Artéria Coronariana/diagnóstico por imagem , Angiografia Coronária/métodos , Imagem de Perfusão do Miocárdio/métodos , Perfusão , Valor Preditivo dos Testes
16.
Cancers (Basel) ; 15(15)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37568811

RESUMO

Indeterminate thyroid nodules (ITNs) are characterized by an expected malignancy ranging from 5% to 30%, with most patients undergoing a diagnostic, rather than therapeutic, operation. The aim of our study was to compare the approach to ITNs across different regions of the world. In this retrospective, multicentric, international study, according to the WHO classification, we identified the South East Asian Region (SEAR), the Americas Region (AMR), the Eastern Mediterranean Region (EMR), the Europe Region (EUR), and the Western Pacific Region (WPR). One high-volume thyroid centre was included for each region. Demographic, preoperative, and pathologic data were compared among the different regions. Overall, 5737 patients from five high-volume thyroid centres were included in this study. We found that the proportion of ITNs over the global activity for thyroid disease was higher in the EUR (37.6%) than in the other regions (21.1-23.6%). In the EMR, the patients were significantly younger (with a mean of 43.1 years) than in the other regions (range, 48.8-57.4 years). The proportion of lobectomy was significantly higher in the WPR, where 83.2% (114/137) of patients received this treatment, than in the other regions, where lobectomies were performed in 44.1-58.1% of patients. The pathological diagnosis of malignancy was significantly higher in the SEAR centre, being over 60%, than in centres of the other regions, where it ranged from 26.3% to 41.3%. The occurrence of lymph node metastases was higher in the WPR (27.8%), AMR (26.9%), and EMR (20%) centres than in the EUR and SEAR centres, where it was lower than 10%. In summary, we found in our study different approaches and outcomes in the diagnosis and treatment of ITNs among countries. Overall, almost 60% of patients with ITNs who underwent surgery actually presented a benign disease, potentially undergoing an unnecessary operation.

17.
Sci Total Environ ; 897: 165309, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37406699

RESUMO

Nutrients supplied via seabird guano increase primary production in some coastal ecosystems. A similar process may occur in the open ocean. To investigate this directly, we first measured bulk and leachable nutrient concentrations in guano sampled in the North Atlantic. We found that guano was strongly enriched in phosphorus, which was released as phosphate in solution. Nitrogen release was dominated by reduced forms (ammonium and urea) whilst release of nitrate was relatively low. A range of trace elements, including the micronutrient iron, were released. Using in-situ bioassays, we then showed that supply of fresh guano to ambient seawater increases phytoplankton biomass and photochemical efficiencies. Based on these results, modelled seabird distributions, and known defecation rates, we estimate that on annual scales guano is a minor source of nutrients for the surface North Atlantic. However, on shorter timescales in late spring/summer it could be much more important: Estimates of upper-level depositions of phosphorus by seabirds were three orders of magnitude higher than modelled aerosol deposition and comparable to diffusion from deeper waters.


Assuntos
Ecossistema , Nitrogênio , Animais , Nitrogênio/análise , Água do Mar , Fitoplâncton , Fósforo , Aves , Oceano Atlântico
18.
PLoS One ; 18(7): e0288270, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37418474

RESUMO

Depressive symptoms have been shown to be negatively related to academic achievement, as measured by grade point average (GPA). Grit, or the passion for and the ability to persevere toward a goal despite adversity, has been linked to GPA. Thus, grit may potentially buffer against the negative effects of depressive symptoms in relation to academic achievement. However, social desirability may might impact the validity of grit when assessed by self-report measures, so how these constructs are all related is unknown. The current study explored the relationship between depressive symptoms, grit, social desirability, and GPA among University students (N = 520) in the United States using a cross-sectional design. We conducted a moderated-moderation model to examine how social desirability moderated the relationship between depressive symptoms, grit, and GPA. Findings replicated prior work and indicated negative relationships between depressive symptoms and social desirability with GPA and a positive relationship, albeit non-significant, between grit and GPA. However, results suggest that grit did not moderate the relationship between depressive symptoms and GPA when including social desirability in the model. Future research should investigate this relationship in a longitudinal setting to further examine how grit and depressive symptoms influence one another in academic domains.


Assuntos
Sucesso Acadêmico , Humanos , Logro , Depressão , Estudos Transversais , Motivação
20.
Sci Total Environ ; 874: 162305, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36801409

RESUMO

Tire and road wear particles (TRWP) are produced by abrasion at the interface of the pavement and tread surface and contain tread rubber with road mineral encrustations. Quantitative thermoanalytical methods capable of estimating TRWP concentrations are needed to assess the prevalence and environmental fate of these particles. However, the presence of complex organic constituents in sediment and other environmental samples presents a challenge to the reliable determination of TRWP concentrations using current pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) methodologies. We are unaware of a published study evaluating pretreatment and other method refinements for microfurnace Py-GC-MS analysis of the elastomeric polymers in TRWP including polymer-specific deuterated internal standards as specified in ISO Technical Specification (ISO/TS) 20593:2017 and ISO/TS 21396:2017. Thus, potential method refinements were evaluated for microfurnace Py-GC-MS, including chromatography parameter modification, chemical pretreatment, and thermal desorption for cryogenically-milled tire tread (CMTT) samples in an artificial sediment matrix and a sediment field sample. The tire tread dimer markers used for quantification were 4-vinylcyclohexene (4-VCH), a marker for styrene-butadiene rubber (SBR) and butadiene rubber (BR), 4-phenylcyclohexene (4-PCH), a marker for SBR, and dipentene (DP), a marker for natural rubber (NR) or isoprene. The resultant modifications included optimization of GC temperature and mass analyzer settings, along with sample pretreatment with potassium hydroxide (KOH) and thermal desorption. Peak resolution was improved while minimizing matrix interferences with overall accuracy and precision consistent with those typically observed in environmental sample analysis. The initial method detection limit for an artificial sediment matrix was approximately 180 mg/kg for a 10 mg sediment sample. A sediment and a retained suspended solids sample were also analyzed to illustrate the applicability of microfurnace Py-GC-MS towards complex environmental sample analysis. These refinements should help encourage the adoption of pyrolysis techniques for mass-based measurements of TRWP in environmental samples both near and distant from roadways.

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