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1.
Inorg Chem ; 63(28): 12785-12802, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38954760

RESUMO

Ordered oxygen vacancies (OOVs) in perovskites can exhibit long-range order and may be used to direct materials properties through modifications in electronic structures and broken symmetries. Based on the various vacancy patterns observed in previously known compounds, we explore the ordering principles of oxygen-deficient perovskite oxides with ABO2.5 stoichiometry to identify other OOV variants. We performed first-principles calculations to assess the OOV stability on a data set of 50 OOV structures generated from our bespoke algorithm. The algorithm employs uniform planar vacancy patterns on (111) pseudocubic perovskite layers and the approach proves effective for generating stable OOV patterns with minimal computational loads. We find as expected that the major factors determining the stability of OOV structures include coordination preferences of transition metals and elastic penalties resulting from the assemblies of polyhedra. Cooperative rotational modes of polyhedra within the OOV structures reduce elastic instabilities by optimizing the bond valence of A- and B cations. This finding explains the observed formation of vacancy channels along low-index crystallographic directions in prototypical OOV phases. The identified ordering principles enable us to devise other stable vacancy patterns with longer periodicity for targeted property design in yet to be synthesized compounds.

2.
Proc Biol Sci ; 291(2026): 20232915, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38981519

RESUMO

Archaeological studies of pre-historic Arctic cultures are often limited to artefacts and architecture; such records may be incomplete and often do not provide a continuous record of past occupation. Here, we used lake sediment archives to supplement archaeological evidence to explore the history of Thule and Dorset populations on Somerset Island, Nunavut (Canada). We examined biomarkers in dated sediment cores from two ponds adjacent to abandoned Thule settlements (PaJs-3 and PaJs-13) and compared these to sediment cores from two ponds without past human occupation. Coprostanol and epicoprostanol, δ15N measurements, sedimentary chlorophyll a and the ratio of diatom valves to chrysophyte cysts were elevated in the dated sediment profiles at both sites during Thule and Dorset occupations. Periods of pronounced human impact during the Thule occupation of the site were corroborated by 14C-dated caribou bones found at both sites that identified intense caribou hunting between ca 1185 and 1510 CE. Notably, these sediment core data show evidence of the Dorset occupation from ca 200 to 500 CE at sites where archaeological evidence was heretofore lacking. We highlight the utility of lake sediments in assisting archaeological studies to better establish the timings, peak occupations and even lifestyle practices of the Dorset and Thule Arctic peoples.


Assuntos
Arqueologia , Biomarcadores , Osso e Ossos , Sedimentos Geológicos , Sedimentos Geológicos/química , Sedimentos Geológicos/análise , Regiões Árticas , Osso e Ossos/química , Animais , Humanos , Biomarcadores/análise , Nunavut , Rena , Lagos/química
3.
Neurobiol Dis ; : 106602, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39004234

RESUMO

Clinical studies have reported that increased epileptiform and subclinical epileptiform activity can be detected in many patients with an Alzheimer's disease (AD) diagnosis using electroencephalogram (EEG) and this may correlate with poorer cognition. Ascorbate may have a specific role as a neuromodulator in AD as it is released concomitantly with glutamate reuptake following excitatory neurotransmission. Insufficiency may therefore result in an exacerbated excitatory/inhibitory imbalance in neuronal signaling. Using a mouse model of AD that requires dietary ascorbate (Gulo-/-APPswe/PSEN1dE9), EEG was recorded at baseline and during 4 weeks of ascorbate depletion in young (5-month-old) and aged (20-month-old) animals. Data were scored for changes in quantity of spike trains, individual spikes, sleep-wake rhythms, sleep fragmentation, and brainwave power bands during light periods each week. We found an early increase in neuronal spike discharges with age and following ascorbate depletion in AD model mice and not controls, which did not correlate with brain amyloid load. Our data also show more sleep fragmentation with age and with ascorbate depletion. Additionally, changes in brain wave activity were observed within different vigilance states in both young and aged mice, where Gulo-/-APPswe/PSEN1dE9 mice had shifts towards higher frequency bands (alpha, beta, and gamma) and ascorbate depletion resulted in shifts towards lower frequency bands (delta and theta). Microarray data supported ascorbate insufficiency altering glutamatergic transmission through the decreased expression of glutamate related genes, however no changes in protein expression of glutamate reuptake transporters were observed. These data suggest that maintaining optimal brain ascorbate levels may support normal brain electrical activity and sleep patterns, particularly in AD patient populations where disruptions are observed.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38946635

RESUMO

BACKGROUND: Globally, viral hepatitis is decreasing, but nonalcoholic fatty liver disease (NAFLD), now metabolic dysfunction-associated steatotic liver disease (MASLD), is increasing. We assessed the burden and trends of MASLD and viral hepatitis in Saudi Arabia. METHODS: Prevalence, death, and disability data due to MASLD, hepatitis C virus (HCV), and hepatitis B virus (HBV) were obtained from 2019 Global Burden of Disease (GBD) database for Saudi Arabia. Time trends were assessed by annual percent change (APC) from joinpoint regression. RESULTS: From 2012 through 2019, MASLD prevalence in children and adults increased from 28.02% (n = 8.34 million) to 33.11% (n = 11.83 million); APC +2.43% (95% confidence interval: 2.33% to 2.54%). HBV prevalence decreased from 1.83% (n = 0.54 million) to 1.53% (n = 0.55 million); APC -1.74% (-2.66% to -0.81%). HCV prevalence stabilized from 0.72% (n = 0.21 million) to 0.73% (n = 0.26 million): APC +0.32% (-0.13% to 0.78%). Among adults (>20 years), MASLD prevalence increased from 40.64% to 43.95% (APC = +1.15%, 1.12% to 1.18%), HBV prevalence decreased from 2.67% to 2.05% (APC = -2.96%, -3.90% to -2.01%), and HCV leveled from 0.88% to 0.86% (APC = -0.30%, -0.75% to 0.16%). MASLD liver mortality rate from liver cancer and cirrhosis increased: APC of +1.15% (0.82% to 1.48%) from 1.31 to 1.43 (per 100,000). HBV and HCV liver mortality increased at slower rates (APC = +0.78%, 0.38% to 1.19%): 2.07 to 2.20 (per 100,000) and (APC = +0.55%, 0.09% to 0.89%): 6.32 to 6.61 (per 100,000), respectively. CONCLUSIONS: MASLD burden is increasing, while HBV and HCV burden is decreasing/remaining stable. Early prevention and diagnosis health policies for MASLD are needed.

5.
Death Stud ; : 1-15, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950572

RESUMO

The COVID-19 pandemic changed the way people lived, but also the way they died. It accentuated the physical, psychological, social, and spiritual vulnerabilities of patients approaching death. This study explored the lived experience of palliative inpatients during the pandemic. We conducted interviews with 22 palliative inpatients registered in a Canadian urban palliative care program, aimed to uncover how the pandemic impacted participants' experiences of approaching end-of-life. The reflexive thematic analysis revealed 6 themes: putting off going into hospital, the influence of the pandemic on hospital experience, maintaining dignity in care, emotional impact of nearing death, making sense of end-of-life circumstances and coping with end-of-life. Findings highlight the vulnerability of patients approaching death, and how that was accentuated during the pandemic. Findings reveal how the pandemic strained, threatened, and undermined human connectedness. These lived experiences of palliative inpatients offer guidance for future pandemic planning and strategies for providing optimal palliative care.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38950771

RESUMO

OBJECTIVE: Research into the risk factors associated with late recurrence (>2 years after surgery) of lung adenocarcinoma (LUAD) is limited. We investigated the incidence of and clinicopathologic and genomic features associated with late recurrence of resected stage I-IIIA LUAD. METHODS: We performed a retrospective analysis of patients with completely resected pathologic stage I-IIIA LUAD (2010-2019). Patients with a history of lung cancer, neoadjuvant therapy, or mucinous or noninvasive LUAD, or with follow-up of <2 years were excluded. Cox and logistic regression modeling were used to compare clinicopathologic variables among patients with no, early (≤2 years), and late recurrence. Comparisons of genomic mutations were corrected for multiple testing. RESULTS: Of the 2349 patients included, 537 developed a recurrence during follow-up. Most recurrences (55% [297/537]) occurred early; 45% (240/537) occurred late. A larger proportion of late recurrences than early recurrences were locoregional (37% vs. 29%; p=0.047). Patients with late recurrence had more aggressive pathologic features (IASLC grade 2 and 3, lymphovascular invasion, visceral pleural invasion) and higher stage than patients without recurrence. Pathologic features were similar between patients with early and late recurrence, except stage IIIA disease was more common in the early cohort. No genomic mutations were associated with late recurrence. CONCLUSIONS: Late recurrence of LUAD following resection is more common than previously reported. Patients without disease >2 years after surgery who had aggressive pathologic features at the time of resection have an elevated risk of recurrence and may benefit from more-aggressive follow-up.

8.
Circ Cardiovasc Interv ; : e014088, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38994599

RESUMO

BACKGROUND: In hemodynamically stable patients with acute pulmonary embolism (PE), the Composite Pulmonary Embolism Shock (CPES) score predicts normotensive shock. However, it is unknown if CPES predicts adverse clinical outcomes. The objective of this study was to determine whether the CPES score predicts in-hospital mortality, resuscitated cardiac arrest, or hemodynamic deterioration. METHODS: Patients with acute intermediate-risk PE admitted from October 2016 to July 2019 were included. CPES was calculated for each patient. The primary outcome was a composite of in-hospital mortality, resuscitated cardiac arrest, or hemodynamic decompensation. Secondary outcomes included individual components of the primary outcome. The association of CPES with primary and secondary outcomes was evaluated. RESULTS: Among the 207 patients with intermediate-risk PE (64.7% with intermediate-high risk PE), 29 (14%) patients had a primary outcome event. In a multivariable model, a higher CPES score was associated with a worse primary composite outcome (adjusted hazard ratio [aHR], 1.81 [95% CI, 1.29-2.54]; P=0.001). Moreover, a higher CPES score predicted death (aHR, 1.76 [95% CI, 1.04-2.96]; P=0.033), resuscitated cardiac arrest (aHR, 1.99 [95% CI, 1.17-3.38]; P=0.011), and hemodynamic decompensation (aHR, 1.96 [95% CI, 1.34-2.89]; P=0.001). A high CPES score (≥3) was associated with the worse primary outcome when compared with patients with a low CPES score (22% versus 2.4%; P=0.003; aHR, 6.48 [95% CI, 1.49-28.04]; P=0.012). CPES score provided incremental prognostic value for the prediction of primary outcome over baseline demographics and European Society of Cardiology intermediate-risk subcategories (global Χ2 value increased from 0.63 to 1.39 to 13.69; P=0.005). CONCLUSIONS: In patients with acute intermediate-risk PE, the CPES score effectively risk stratifies and prognosticates patients for the prediction of clinical events and provides incremental value over baseline demographics and European Society of Cardiology intermediate-risk subcategories.

9.
J Addict Med ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012008

RESUMO

OBJECTIVE: To examine the quarterly incidence and prevalence of medications for opioid use disorder (OUD) and alcohol use disorder (AUD) from 2015 to 2021. METHODS: A retrospective population-wide observational study in Manitoba, Canada, was conducted using administrative claims data from the Manitoba Centre for Health Policy to examine the incidence and prevalence of OUD (methadone, buprenorphine-naloxone, buprenorphine) or AUD medications (naltrexone, acamprosate, disulfiram) per 10,000 individuals in each quarter between January 1, 2015, and December 31, 2021. RESULTS: There were 1179 and 451 individuals who received at least one prescription for OUD and AUD, respectively, in the first quarter of 2020. The prevalence of OUD medications more than doubled from 6.3 to 14.3 per 10,000 from January 1, 2015, to December 31, 2021. Likewise, AUD medication prevalence increased almost 10-fold from 0.68 to 6.5 per 10,000 from January 1, 2015, to December 31, 2021, primarily due to naltrexone. The incidence of AUD prescription use increased 8.6-fold from 0.29 to 2.51 per 10,000 during the study period. In contrast, the incidence of opioid agonist therapy declined from 2.1 per 10,000 in the first quarter of 2015 to 0.53 per 10,000 the first quarter of 2016, primarily due to methadone. Whereas methadone incidence declined, buprenorphine-naloxone incidence increased almost 15-fold during the study period. CONCLUSION: An increase in both AUD medication prevalence and incidence in addition to an increase in buprenorphine-naloxone incidence was observed. These findings reflect an increase in the uptake of medications for treating AUD and OUD following changes to improve coverage and access to these medications.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38967296

RESUMO

OBJECTIVE: The objective of this study was to identify the transcriptional landscape of insulin resistance (IR) in subcutaneous adipose tissue (SAT) in humans across the spectrum of obesity. METHODS: We used SAT RNA sequencing in 220 individuals with metabolic phenotyping. RESULTS: We identified a 35-gene signature with high predictive accuracy for homeostatic model of IR that was expressed across a variety of non-immune cell populations. We observed primarily "protective" IR associations for adipocyte transcripts and "deleterious" associations for macrophage transcripts, as well as a high concordance between SAT and visceral adipose tissue (VAT). Multiple SAT genes exhibited dynamic expression 5 years after weight loss surgery and with insulin stimulation. Using available expression quantitative trait loci in SAT and/or VAT, we demonstrated similar genetic effect sizes of SAT and VAT on type 2 diabetes and BMI. CONCLUSIONS: SAT is conventionally viewed as a metabolic buffer for lipid deposition during positive energy balance, whereas VAT is viewed as a dominant contributor to and prime mediator of IR and cardiometabolic disease risk. Our results implicate a dynamic transcriptional architecture of IR that resides in both immune and non-immune populations in SAT and is shared with VAT, nuancing the current VAT-centric concept of IR in humans.

11.
bioRxiv ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38979314

RESUMO

Corticostriatal projection neurons from prelimbic medial prefrontal cortex to the nucleus accumbens core critically regulate drug-seeking behaviors, yet the underlying encoding dynamics whereby these neurons contribute to drug seeking remain elusive. Here we use two-photon calcium imaging to visualize the activity of corticostriatal neurons in mice from the onset of heroin use to relapse. We find that the activity of these neurons is highly heterogeneous during heroin self-administration and seeking, with at least 8 distinct neuronal ensembles that display both excitatory and inhibitory encoding dynamics. These neuronal ensembles are particularly apparent during relapse, where excitatory responses are amplified compared to heroin self-administration. Moreover, we find that optogenetic inhibition of corticostriatal projection neurons attenuates heroin seeking regardless of the relapse trigger. Our results reveal the precise corticostriatal activity dynamics underlying drug-seeking behaviors and support a key role for this circuit in mediating relapse to drug seeking.

12.
Nat Commun ; 15(1): 5447, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992007

RESUMO

Air pollution has the potential to disrupt ecologically- and economically-beneficial services provided by invertebrates, including pollination and natural pest regulation. To effectively predict and mitigate this disruption requires an understanding of how the impacts of air pollution vary between invertebrate groups. Here we conduct a global meta-analysis of 120 publications comparing the performance of different invertebrate functional groups in unpolluted and polluted atmospheres. We focus on the pollutants ozone, nitrogen oxides, sulfur dioxide and particulate matter. We show that beneficial invertebrate performance is reduced by air pollution, whereas the performance of plant pest invertebrates is not significantly affected. Ozone pollution has the most detrimental impacts, and these occur at concentrations below national and international air quality standards. Changes in invertebrate performance are not dependent on air pollutant concentrations, indicating that even low levels of pollution are damaging. Predicted increases in tropospheric ozone could result in unintended consequences to global invertebrate populations and their valuable ecological services.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Invertebrados , Ozônio , Material Particulado , Animais , Poluição do Ar/efeitos adversos , Invertebrados/efeitos dos fármacos , Ozônio/toxicidade , Ozônio/efeitos adversos , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/efeitos adversos , Material Particulado/efeitos adversos , Dióxido de Enxofre/toxicidade , Óxidos de Nitrogênio/toxicidade , Polinização
13.
Physiol Behav ; 284: 114637, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38997097

RESUMO

Boredom, a complex emotional state with implications for mental health and well-being, has garnered attention across disciplines, yet remains relatively understudied in psychiatric research. Here, we explored the intricate relationship between trait-impulsivity, stress, and boredom across two studies. Participants completed self-report measures of trait-impulsivity and boredom and boredom-inducing tasks. Study 1, involving 80 participants (42 women and 38 men, aged 20-63), replicates previous findings, by demonstrating that impulsive individuals report greater boredom following a boring task. Study 2 then extends this, using 20 participants (9 women and 12 men, aged 18-24), to show that hypothalamic-pituitary-adrenal (HPA) axis activity, specifically heightened salivary cortisol responses, mediate the link between impulsivity and boredom following a boring task. Collectively, these results demonstrate that HPA axis activity may underline the relationship between trait-impulsivity and boredom by extending previous work and offering a novel insight into potential mechanisms. These findings offer promise for personalised interventions, designed for high impulsivity individuals, to alleviate the negative impacts of boredom and potentially break the identified feedback loop.

14.
Exp Psychol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953662

RESUMO

In the verbal domain, it is well established that words read aloud are better remembered than their silently read counterparts. It has been hypothesized that this production effect stems from the addition of distinctive features, with the caveat that the processing that generates added features interferes with rehearsal. Here, we tested the idea that a similar trade-off is found in the visuospatial domain. In all experiments, a short series of single dots sequentially appeared at various locations on a screen. Participants produced the items by clicking on them at presentation, watched the items appear quietly, or produced an irrelevant click after each item to better even out rehearsal opportunities between produced and control conditions. In Experiment 1, the dots appeared within a visible grid and an order reconstruction task was used. Experiment 2 also called upon reconstruction, but with the grid removed. In Experiments 3, a recall task was used. The results show that producing items hindered performance compared to the control condition. Conversely, production improved performance compared to the control condition where rehearsal was hindered. This is the first demonstration of a visuospatial production effect. The key findings were successfully modeled by the Revised Feature Model (RFM).

15.
Artigo em Inglês | MEDLINE | ID: mdl-38954830

RESUMO

Composite end-points are common primary outcomes in clinical trials. Their main benefit of utilizing a composite outcome is increasing the number of primary outcome events meaning fewer participants are required to deliver an adequately powered trial. By combining multiple important end-points in the primary outcome rather than having to select only one, composite end-points potentially make clinically meaningful benefits easier to detect and avoid ranking outcomes hierarchically. However there are a number of important considerations when designing and interpreting clinical trials that utilize composite end-points. In this Statistical Primer, issues with composite end-points such as competing events, halo effect, risk of bias, time to event limitations and the win ratio are discussed in the context of real world clinical trials.

16.
South Med J ; 117(7): 383-388, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38959968

RESUMO

OBJECTIVES: This study aimed to report geographic and demographic patterns of patients with craniosynostosis (CS) treated at Children's of Mississippi, the state's only American Cleft Palate-Craniofacial Association-approved craniofacial team. METHODS: Patients with CS were treated at a tertiary pediatric hospital cared for by craniofacial surgeons and neurosurgeons from 2015 to 2020. Demographic, geographic, and CS diagnosis details, including sex, gestational age, race, ethnicity, insurance status, and affected cranial suture type(s), number, and associated syndromic diagnosis were collected, including birth county and total live births from state data. Significant differences between prevalence of CS in four regions of Mississippi were examined using two-tailed t tests (P < 0.05). RESULTS: Among 222,819 live births in Mississippi between 2015 and 2020, 79 pediatric patients presented to Children's of Mississippi with CS, with an overall incidence of 0.355/1000 live births. Most cases were nonsyndromic CS (82%, n = 65) affecting a single major cranial suture (81%, n = 64). The overall incidence of CS was higher in the coastal and central regions compared with northeast Mississippi, at 0.333 and 0.527 vs 0.132/1000 live births (P = 0.012 and P = 0.004), respectively. CONCLUSIONS: Results from this study suggest regional patterns of CS in Mississippi, which may reflect actual incidence patterns or proximity to Children's of Mississippi. Further study could reveal regional differences in risk factors underlying CS incidence or access to specialized CS care for different regions in the state. This will lead to opportunities for institutional outreach to decrease the burden of CS care in Mississippi.


Assuntos
Craniossinostoses , Humanos , Mississippi/epidemiologia , Craniossinostoses/epidemiologia , Craniossinostoses/diagnóstico , Feminino , Masculino , Lactente , Prevalência , Incidência , Recém-Nascido , Pré-Escolar
17.
Adv Ther ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963587

RESUMO

INTRODUCTION: Trofinetide is the first drug to be approved for the treatment of Rett syndrome. Hepatic impairment is not expected to affect the pharmacokinetic (PK) profile of trofinetide because of predominant renal excretion. This study was conducted to help understand the potential impact of any hepatic impairment on trofinetide PK. METHODS: This study used physiologically based PK modeling to estimate trofinetide exposure (maximum drug concentration and area under the concentration-time curve from time zero to infinity) in virtual patients with mild, moderate, and severe hepatic impairment (per Child-Pugh classification) compared with virtual healthy subjects following a 12 g oral trofinetide dose. RESULTS: In individual deterministic simulations for matched individuals and stochastic simulations at the population level (100 virtual individuals simulated per population), as anticipated, predicted plasma exposures were similar for healthy subjects and for patients with mild, moderate, and severe hepatic impairment. However, predicted blood concentration exposures slightly increased with increasing severity of hepatic impairment because of change in hematocrit levels. CONCLUSION: This study indicates that hepatic impairment is not expected to have a clinically relevant effect on exposure to trofinetide.


Trofinetide is the first approved treatment for Rett syndrome, a rare genetic condition that affects brain development. When a person takes trofinetide, most is removed from the body via the urine in its unchanged form (no chemical alteration). Regulatory requirements mean researchers must confirm the safety of any pharmaceutical drug and evaluate whether changes in liver function lead to harmful levels of drug exposure. Researchers used a computer model to predict how much trofinetide would be present in the blood and plasma (the liquid portion of blood) over time in virtual healthy subjects and virtual patients with varying degrees of liver disease (mild, moderate, or severe). Computer simulations showed that predicted trofinetide levels in plasma were similar in virtual healthy subjects and each virtual patient group with liver disease. Predicted levels of trofinetide in blood were slightly elevated with increasing severity of liver disease. This is because people with liver disease have fewer red blood cells, so the cell portion of blood becomes smaller relative to the liquid portion (plasma), which leads to higher trofinetide concentrations in whole blood (trofinetide minimally enters the red blood cell). The small increase in trofinetide levels in blood and the absence of any change in trofinetide levels in plasma means that people with Rett syndrome and liver disease are unlikely to be exposed to harmful levels of trofinetide after a 12 g oral dose.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38956275

RESUMO

BACKGROUND & OBJECTIVE: Disposable face masks are a primary protective measure against the adverse health effects of exposure to infectious and toxic aerosols such as airborne viruses and particulate air pollutants. While the fit of high efficiency respirators is regulated in occupational settings, relatively little is known about the fitted filtration efficiencies of ear loop style face masks worn by the public. METHODS: We measured the variation in fitted filtration efficiency (FFE) of four commonly worn disposable face masks, in a cohort of healthy adult participants (N = 100, 50% female, 50% male, average age = 32.3 ± 9.2 years, average BMI = 25.5 ± 3.4) using the U.S. Occupational Safety and Health Administration Quantitative Fit Test, for an N95 (respirator), KN95, surgical, and KF94 masks. The latter three ear loop style masks were additionally tested in a clip-modified condition, tightened using a plastic clip to centrally fasten loops in the back of the head. RESULTS: The findings show that sex is a major determinant of the FFE of KN95, surgical, and KF94 masks. On average, males had an 11% higher FFE relative to females, at baseline testing. We show that a simple modification using an ear loop clip, results in improvements in the average FFE for females but provides comparatively minor changes for males. On average, females had a 20% increased FFE when a clip was worn behind the head, relative to a 6% increase for males. IMPACT: The efficacy of a disposable face mask as protection against air contaminants depends on the efficiency of the mask materials and how well it fits the wearer. We report that the sex of the wearer is a major determinant of the baseline fitted filtration efficiency (FFE) of commonly available ear loop style face masks. In addition, we show that a simple fit modifier, an ear loop clip fastened behind the head, substantially improves baseline FFE for females but produces only minor changes for males. These findings have significant public health implications for the use of face masks as a protective intervention against inhalational exposure to airborne contaminants.

20.
J Chem Inf Model ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958581

RESUMO

One of the most challenging tasks in modern medicine is to find novel efficient cancer therapeutic methods with minimal side effects. The recent discovery of several classes of organic molecules known as "molecular jackhammers" is a promising development in this direction. It is known that these molecules can directly target and eliminate cancer cells with no impact on healthy tissues. However, the underlying microscopic picture remains poorly understood. We present a study that utilizes theoretical analysis together with experimental measurements to clarify the microscopic aspects of jackhammers' anticancer activities. Our physical-chemical approach combines statistical analysis with chemoinformatics methods to design and optimize molecular jackhammers. By correlating specific physical-chemical properties of these molecules with their abilities to kill cancer cells, several important structural features are identified and discussed. Although our theoretical analysis enhances understanding of the molecular interactions of jackhammers, it also highlights the need for further research to comprehensively elucidate their mechanisms and to develop a robust physical-chemical framework for the rational design of targeted anticancer drugs.

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