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The heterogeneity of the viscoelasticity of a lamellar gel network based on cetyl-trimethylammonium chloride and cetostearyl alcohol was studied using particle-tracking microrheology. A recurrent neural network (RNN) architecture was used for estimating the Hurst exponent, H, on small sections of tracks of probe spheres moving with fractional Brownian motion. Thus, dynamic segmentation of tracks via neural networks was used in microrheology and it is significantly more accurate than using mean square displacements (MSDs). An ensemble of 414 particles produces a MSD that is subdiffusive in time, t, with a power law of the form t^{0.74±0.02}, indicating power law viscoelasticity. RNN analysis of the probability distributions of H, combined with detailed analysis of the time-averaged MSDs of individual tracks, revealed diverse diffusion processes belied by the simple scaling of the ensemble MSD, such as caging phenomena, which give rise to the complex viscoelasticity of lamellar gels.
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Identifying an integrative framework that could appropriately delineate underlying mechanisms and individual risk/protective factors for human health has remained elusive. Evolutionary mismatch theory provides a comprehensive, integrative model for understanding the underlying causes and mechanisms of a wide range of modern health and well-being problems, ranging from obesity to depression. Despite growing interest regarding its importance though, no psychometrically-sound measure of evolutionary mismatch yet exists to facilitate research and intervention. To construct such a scale, aimed at gauging individual differences in the extent to which people's modern lifestyles are mismatched with ancestral conditions, we conducted four studies (a pilot study, followed by 3 main studies, with a final sample of 1901 participants across the main studies). Results from exploratory and confirmatory factor analyses have produced a 36-item evolutionary mismatched lifestyle scale (EMLS) with 7 subdomains of mismatched behaviours (e.g., diet, physical activity, relationships, social media use) that is psychometrically sound. Further, the EMLS is associated with physical, mental and subjective health. We explore the potential of the EMLS as a tool for examining interpersonal and cultural variations in health and wellbeing, while also discussing the limitations of the scale and future directions in relation to further psychometric examinations.
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Ultra-Clean-Air (UCA) operating theatres aim to minimise surgical instrument contamination and wound infection through high flow rates of ultra-clean air, reducing the presence of Microbe Carrying Particles (MCPs). This study investigates the airflow patterns and ventilation characteristics of a UCA operating theatre (OT) under standard ventilation system operating conditions, considering both empty and partially occupied scenarios. Utilising a precise computational model, quasi-Direct Numerical Simulations (qDNS) were conducted to delineate flow velocity profiles, energy spectra, distributions of turbulent kinetic energy, energy dissipation rate, local Kolmogorov scales, and pressure-based coherent structures. These results were also complemented by a tracer gas decay analysis following ASHRAE standard guidelines. Simulations showed that contrary to the intended laminar regime, the OT's geometry inherently fosters a predominantly turbulent airflow, sustained until evacuation through the exhaust vents, and facilitating recirculation zones irrespective of occupancy level. Notably, the occupied scenario demonstrated superior ventilation efficiency, a phenomenon attributed to enhanced kinetic energy induced by the additional obstructions. The findings underscore the critical role of UCA-OT design in mitigating MCP dissemination, highlighting the potential to augment the design to optimise airflow across a broader theatre spectrum, thereby diminishing recirculation zones and consequently reducing the propensity for Surgical Site Infections (SSIs). The study advocates for design refinements to harness the turbulent dynamics beneficially, steering towards a safer surgical environment.
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While previous studies guided by evolutionary life history theory have revealed several important socioecological moderators of the influence of population density (PD) on reproduction, absent is an understanding of how individual-level factors such as personal resources and sex differences might interact and play a role. Using data from a large sample of clients (N = 4,432,440) of an online dating company spanning 317 states nested within 23 countries, we contributed a robust multilevel analysis of life history effects by assessing the interaction between state-level PD and individual-level income on offspring quantity, and we further qualified this analysis by sex. Consistent with previous research, PD was negatively correlated with having children. Consistent with our novel hypotheses, this negative relationship was moderated by income such that the link between PD and low fertility became weaker with increasing levels of income and these patterns were stronger for men than for women. These results held despite controlling for a variety of country-level, state-level, and individual-level confounds. Findings are discussed together with theoretical and practical implications for the management of fertility based on evolutionary life history perspectives.
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The gut microbiota influences the clinical responses of cancer patients to immunecheckpoint inhibitors (ICIs). However, there is no consensus definition of detrimental dysbiosis. Based on metagenomics (MG) sequencing of 245 non-small cell lung cancer (NSCLC) patient feces, we constructed species-level co-abundance networks that were clustered into species-interacting groups (SIGs) correlating with overall survival. Thirty-seven and forty-five MG species (MGSs) were associated with resistance (SIG1) and response (SIG2) to ICIs, respectively. When combined with the quantification of Akkermansia species, this procedure allowed a person-based calculation of a topological score (TOPOSCORE) that was validated in an additional 254 NSCLC patients and in 216 genitourinary cancer patients. Finally, this TOPOSCORE was translated into a 21-bacterial probe set-based qPCR scoring that was validated in a prospective cohort of NSCLC patients as well as in colorectal and melanoma patients. This approach could represent a dynamic diagnosis tool for intestinal dysbiosis to guide personalized microbiota-centered interventions.
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Carcinoma Pulmonar de Células não Pequenas , Microbioma Gastrointestinal , Imunoterapia , Neoplasias Pulmonares , Neoplasias , Feminino , Humanos , Masculino , Akkermansia , Carcinoma Pulmonar de Células não Pequenas/microbiologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/imunologia , Disbiose/microbiologia , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia/métodos , Neoplasias Pulmonares/microbiologia , Neoplasias Pulmonares/tratamento farmacológico , Metagenômica/métodos , Neoplasias/microbiologia , Resultado do TratamentoRESUMO
Biological soil crusts, or biocrusts, are microbial communities found in soil surfaces in drylands and in other locations where vascular plant cover is incomplete. They are functionally significant for numerous ecosystem services, most notably in the C fixation and storage due to the ubiquity of photosynthetic microbes. Whereas carbon fixation and storage have been well studied in biocrusts, the composition, function and characteristics of other organisms in the biocrust such as heterotrophic bacteria and especially fungi are considerably less studied and this limits our ability to gain a holistic understanding of biocrust ecology and function. In this research we characterised the fungal community in biocrusts developed on Kalahari Sand soils from a site in southwest Botswana, and combined these data with previously published bacterial community data from the same site. By identifying organisational patterns in the community structure of fungi and bacteria, we found fungi that were either significantly associated with biocrust or the soil beneath biocrusts, leading to the conclusion that they likely perform functions related to the spatial organisation observed. Furthermore, we showed that within biocrusts bacterial and fungal community structures are correlated with each other i.e., a change in the bacterial community is reflected by a corresponding change in the fungal community. Importantly, this correlation but that this correlation does not occur in nearby soils. We propose that different fungi engage in short-range and long-range interactions with dryland soil surface bacteria. We have identified fungi which are candidates for further studies into their potential roles in biocrust ecology at short ranges (e.g., processing of complex compounds for waste management and resource provisioning) and longer ranges (e.g., translocation of resources such as water and the fungal loop model). This research shows that fungi are likely to have a greater contribution to biocrust function and dryland ecology than has generally been recognised.
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[This corrects the article DOI: 10.1371/journal.pone.0301176.].
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OBJECTIVE: The endothelium regulates crucial aspects of vascular function, including hemostasis, vasomotor tone, proliferation, immune cell adhesion, and microvascular permeability. Endothelial cells (ECs), especially in arterioles, are pivotal for flow distribution and peripheral resistance regulation. Investigating vascular endothelium physiology, particularly in microvascular ECs, demands precise isolation and culturing techniques. METHODS: Freshly isolated ECs are vital for examining protein expression, ion channel behavior, and calcium dynamics. Establishing primary endothelial cell cultures is crucial for unraveling vascular functions and understanding intact microvessel endothelium roles. Despite the significance, detailed protocols and comparisons with intact vessels are scarce in microvascular research. We developed a reproducible method to isolate microvascular ECs, assessing substrate influence by cultivating cells on fibronectin and gelatin matrix gels. This comparative approach enhances our understanding of microvascular endothelial cell biology. RESULTS: Microvascular mesenteric ECs expressed key markers (VE-cadherin and eNOS) in both matrix gels, confirming cell culture purity. Under uncoated conditions, ECs were undetected, whereas proteins linked to smooth muscle cells and fibroblasts were evident. Examining endothelial cell (EC) physiological dynamics on distinct matrix substrates revealed comparable cell length, shape, and Ca2+ elevations in both male and female ECs on gelatin and fibronectin matrix gels. Gelatin-cultured ECs exhibited analogous membrane potential responses to acetylcholine (ACh) or adenosine triphosphate (ATP), contrasting with their fibronectin-cultured counterparts. In the absence of stimulation, fibronectin-cultured ECs displayed a more depolarized resting membrane potential than gelatin-cultured ECs. CONCLUSIONS: Gelatin-cultured ECs demonstrated electrical behaviors akin to intact endothelium from mouse mesenteric arteries, thus advancing our understanding of endothelial cell behavior within diverse microenvironments.
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Células Endoteliais , Gelatina , Microvasos , Óxido Nítrico Sintase Tipo III , Animais , Células Endoteliais/metabolismo , Células Endoteliais/citologia , Camundongos , Feminino , Masculino , Microvasos/citologia , Microvasos/metabolismo , Microvasos/fisiologia , Óxido Nítrico Sintase Tipo III/metabolismo , Células Cultivadas , Fibronectinas/metabolismo , Fibronectinas/farmacologia , Géis , Antígenos CD/metabolismo , Caderinas/metabolismo , Cultura Primária de Células , Endotélio Vascular/metabolismo , Endotélio Vascular/citologiaRESUMO
AIM: This study aims to explore regional variation and identify regions within Australia with high incidence of out-of-hospital cardiac arrest (OHCA) and low rates of bystander cardiopulmonary resuscitation (CPR). METHOD: Adult OHCAs of presumed medical aetiology occurring across Australia between 2017 and 2019 were mapped onto local government areas (LGA) using the location of arrest coordinates. Bayesian spatial models were applied to provide "smoothed" estimates of OHCA incidence and bystander CPR rates (for bystander-witnessed OHCAs) for each LGA. For each state and territory, high-risk LGAs were defined as those with an incidence rate greater than the state or territory's 75th percentile and a bystander CPR rate less than the state or territory's 25th percentile. RESULTS: A total of 62,579 OHCA cases attended by emergency medical services across 543 LGAs nationwide were included in the study. Nationally, the OHCA incidence rate across LGA ranged from 58.5 to 198.3 persons per 100,000, while bystander CPR rates ranged from 45% to 75%. We identified 60 high-risk LGAs, which were predominantly located in the state of New South Wales. Within each region, high-risk LGAs were typically located in regional and remote areas of the country, except for four metropolitan areas-two in Adelaide and two in Perth. CONCLUSIONS: We have identified high-risk LGAs, characterised by high incidence and low bystander CPR rates, which are predominantly in regional and remote areas of Australia. Strategies for reducing OHCA and improving bystander response may be best targeted at these regions.
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Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Parada Cardíaca Extra-Hospitalar/epidemiologia , Parada Cardíaca Extra-Hospitalar/terapia , Humanos , Estudos Retrospectivos , Incidência , Austrália/epidemiologia , Masculino , Serviços Médicos de Emergência/estatística & dados numéricos , Feminino , Idoso , Pessoa de Meia-Idade , AdultoRESUMO
BACKGROUND: Chronic postsurgical pain (CPSP) is common following musculoskeletal and orthopedic surgeries and is associated with impairment and reduced quality of life. Several interventions have been proposed to reduce CPSP; however, there remains uncertainty regarding which, if any, are most effective. We will perform a systematic review and network meta-analysis of randomised trials to assess the comparative benefits and harms of perioperative pharmacological and psychological interventions directed at preventing chronic pain after musculoskeletal and orthopedic surgeries. METHODS: We will search MEDLINE, Embase, PsycINFO, CINAHL, and the Cochrane Central Register of Controlled Trials from inception to present, without language restrictions. We will include randomised controlled trials that as follows: (1) enrolled adult patients undergoing musculoskeletal or orthopedic surgeries; (2) randomized them to any pharmacological or psychological interventions, or their combination directed at reducing CPSP, placebo, or usual care; and (3) assessed pain at 3 months or more after surgery. Screening for eligible trials, data extraction, and risk-of-bias assessment using revised Cochrane risk-of-bias tool (RoB 2.0) will be performed in duplicate and independently. Our main outcome of interest will be the proportion of surgical patients reporting any pain at ≥ 3 months after surgery. We will also collect data on other patient important outcomes, including pain severity, physical functioning, emotional functioning, dropout rate due to treatment-related adverse event, and overall dropout rate. We will perform a frequentist random-effects network meta-analysis to determine the relative treatment effects. When possible, the modifying effect of sex, surgery type and duration, anesthesia type, and veteran status on the effectiveness of interventions will be investigated using network meta-regression. We will use the GRADE approach to assess the certainty evidence and categorize interventions from most to least beneficial using GRADE minimally contextualised approach. DISCUSSION: This network meta-analysis will assess the comparative effectiveness of pharmacological and psychological interventions directed at preventing CPSP after orthopedic surgery. Our findings will inform clinical decision-making and identify promising interventions for future research. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42023432503.
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Dor Crônica , Metanálise em Rede , Procedimentos Ortopédicos , Dor Pós-Operatória , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Procedimentos Ortopédicos/efeitos adversos , Dor Crônica/prevenção & controle , Dor Pós-Operatória/prevenção & controle , Assistência Perioperatória/métodos , Qualidade de VidaRESUMO
Despite data showing that nutritional interventions high in antioxidant/anti-inflammatory properties (anthocyanin-rich foods, such as blueberries/elderberries) may decrease risk of memory loss and cognitive decline, evidence for such effects in mild cognitive impairment (MCI) is limited. This study examined preliminary effects of American elderberry (Sambucus nigra subsp. canadensis) juice on cognition and inflammatory markers in patients with MCI. In a randomized, double-blind, placebo-controlled trial, patients with MCI (n = 24, Mage = 76.33 ± 6.95) received American elderberry (n = 11) or placebo (n = 13) juice (5 mL orally 3 times a day) for 6 months. At baseline, 3 months, and 6 months, patients completed tasks measuring global cognition, verbal memory, language, visuospatial cognitive flexibility/problem solving, and memory. A subsample (n = 12, 7 elderberry/5 placebo) provided blood samples to measure serum inflammatory markers. Multilevel models examined effects of the condition (elderberry/placebo), time (baseline/3 months/6 months), and condition by time interactions on cognition/inflammation outcomes. Attrition rates for elderberry (18%) and placebo (15%) conditions were fairly low. The dosage compliance (elderberry-97%; placebo-97%) and completion of cognitive (elderberry-88%; placebo-87%) and blood-based (elderberry-100%; placebo-100%) assessments was high. Elderberry (not placebo) trended (p = 0.09) towards faster visuospatial problem solving performance from baseline to 6 months. For the elderberry condition, there were significant or significantly trending decreases over time across several markers of low-grade peripheral inflammation, including vasorin, prenylcysteine oxidase 1, and complement Factor D. Only one inflammatory marker showed an increase over time (alpha-2-macroglobin). In contrast, for the placebo, several inflammatory marker levels increased across time (L-lactate dehydrogenase B chain, complement Factor D), with one showing deceased levels over time (L-lactate dehydrogenase A chain). Daily elderberry juice consumption in patients with MCI is feasible and well tolerated and may provide some benefit to visuospatial cognitive flexibility. Preliminary findings suggest elderberry juice may reduce low-grade inflammation compared to a placebo-control. These promising findings support the need for larger, more definitive prospective studies with longer follow-ups to better understand mechanisms of action and the clinical utility of elderberries for potentially mitigating cognitive decline.
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Cognição , Disfunção Cognitiva , Sucos de Frutas e Vegetais , Inflamação , Sambucus , Humanos , Masculino , Idoso , Feminino , Cognição/efeitos dos fármacos , Inflamação/sangue , Método Duplo-Cego , Sambucus/química , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Viabilidade , Sambucus nigra/químicaRESUMO
Multiple clinical trials targeting the gut microbiome are being conducted to optimize treatment outcomes for immune checkpoint blockade (ICB). To improve the success of these interventions, understanding gut microbiome changes during ICB is urgently needed. Here through longitudinal microbiome profiling of 175 patients treated with ICB for advanced melanoma, we show that several microbial species-level genome bins (SGBs) and pathways exhibit distinct patterns from baseline in patients achieving progression-free survival (PFS) of 12 months or longer (PFS ≥12) versus patients with PFS shorter than 12 months (PFS <12). Out of 99 SGBs that could discriminate between these two groups, 20 were differentially abundant only at baseline, while 42 were differentially abundant only after treatment initiation. We identify five and four SGBs that had consistently higher abundances in patients with PFS ≥12 and <12 months, respectively. Constructing a log ratio of these SGBs, we find an association with overall survival. Finally, we find different microbial dynamics in different clinical contexts including the type of ICB regimen, development of immune-related adverse events and concomitant medication use. Insights into the longitudinal dynamics of the gut microbiome in association with host factors and treatment regimens will be critical for guiding rational microbiome-targeted therapies aimed at enhancing ICB efficacy.
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Microbioma Gastrointestinal , Melanoma , Microbiota , Humanos , Microbioma Gastrointestinal/genética , Melanoma/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , CogniçãoRESUMO
This research explores experiences of compassion among 2S/LGBTQ + Canadians living with eating disorders in the context of eating disorder treatment and community support. There is a growing body of scholarship showing disparities in eating disorder care for those within 2S/LGBTQ + communities. Among the reported concerns is a potential lack of compassion in eating disorder treatment and recovery settings, something which may serve to exacerbate feelings of isolation and perpetuate misunderstandings of 2S/LGBTQ + people's experiences. In an effort to understand these dynamics more deeply, we conducted semi-structured interviews with 2S/LGBTQ + Canadians who have experienced eating disorder care. The data collected were then subjected to Foucauldian discourse analysis, which produced three interconnected discursive considerations: feeling lack of structural compassion, 2S/LGBTQ + communities as places of respite, and 2S/LGBTQ + caregiving. One of the common threads among these discursive considerations was cis-heteronormativity ingrained in eating disorder treatment settings and health care systems more broadly. Our findings underscore the critical need for more enhanced compassion for 2S/LGBTQ + patients in eating disorder care settings. We conclude that compassion, when implemented on the levels of individual clinicians, policy and procedure, and institutions, may represent an avenue toward disrupting ingrained cis-heteronormativity and the associated discursive power structures contained in health care systems.
Two-Spirit, lesbian, gay, bisexual, transgender, queer and other sexually or gender diverse (2S/LGBTQ+) are at increased risk for eating disorders often related to minority stress, discrimination, and heteronormative gender expectations. Compassion is believed to be a fundamental aspect of healthcare that builds human connections and enhances positive outcomes. Healthcare, however, is steeped in heteronormative assumptions that may further isolate many 2S/LGBTQ+ patients. This study explored how 2S/LGBTQ+ Canadians living with eating disorders felt about their care and the role of compassion in their recovery journeys. We found that these individuals often felt misunderstood and isolated during treatment. However, they often experienced understanding by connecting with other 2S/LGBTQ+ people both in care and in the community, which provided the compassionate spaces lacking in their healthcare experiences. These findings highlight a need for making healthcare more compassionate for 2S/LGBTQ+ people. This can be done by changing policies, mandatory training for healthcare professionals, and treatment that recognizes and discusses minority stresses, uses trauma-informed practices, and gender-affirming approaches. By doing such items, standard norms can be challenged and the care for 2S/LGBTQ+ people living with eating disorders can be improved.
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Past research suggests that reactions to research on sex differences are often less positive when the findings put men in a better light than women, especially when the lead researcher is a man. The factors underlying this effect, however, are not yet fully understood. The present study aimed to provide the first experimental test of the hypothesis that the key variable is perceived harm to women. Participants (214 men and 219 women) evaluated a bogus popular-science article reporting fictional research finding either a female- or a male-favouring sex difference in intelligence, attributed to either a female or a male lead researcher. To examine the effects of perceived harm, the introduction to the task highlighted either the potential benefits or potential drawbacks of sex-differences research in general. Consistent with past research, participants reacted less positively to the male-favouring difference, especially for male-led research. Consistent with the harm hypothesis, the effect was stronger after highlighting the potential drawbacks of sex-differences research than after highlighting the potential benefits. Our findings suggest that perceptions of harm to women underpin the aversion to male-favouring findings.
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Caracteres Sexuais , Humanos , Feminino , Masculino , Adulto , Adulto Jovem , Percepção Social , Adolescente , Pessoa de Meia-Idade , Sexismo/psicologia , PesquisaRESUMO
BACKGROUND: Following years of sustained pressure on the UK health service, there is recognition amongst health professionals and stakeholders that current models of healthcare are likely to be inadequate going forward. Therefore, a fundamental review of existing social models of healthcare is needed to ascertain current thinking in this area, and whether there is a need to change perspective on current thinking. METHOD: Through a systematic research review, this paper seeks to address how previous literature has conceptualized a social model of healthcare and, how implementation of the models has been evaluated. Analysis and data were extracted from 222 publications and explored the country of origin, methodological approach, and the health and social care contexts which they were set. RESULTS: The publications predominantly drawn from the USA, UK, Australia, Canada and Europe identified five themes namely: the lack of a clear and unified definition of a social model of health and wellbeing; the need to understand context; the need for cultural change; improved integration and collaboration towards a holistic and person-centred approach; measuring and evaluating the performance of a social model of health. CONCLUSION: The review identified a need for a clear definition of a social model of health and wellbeing. Furthermore, consideration is needed on how a model integrates with current models and whether it will act as a descriptive framework or, will be developed into an operational model. The review highlights the importance of engagement with users and partner organizations in the co-creation of a model of healthcare.
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Atenção à Saúde , Humanos , Reino Unido , Canadá , Europa (Continente)RESUMO
Thermodynamic stability assessment of nanocrystal systems requires precise free energy calculations. This study highlights the importance of meticulous control over various factors, including the thermostat, time step, potential cutoff, initial configuration, sampling method, and overall simulation duration. Free energy computations in dry (solvent-free) systems are on the order of several hundred kBT but can be obtained with consistent accuracy. However, calculation of internal energies becomes challenging, as they are typically much larger in magnitude than free energies and exhibit significant noise and reduced reliability. To address this limitation, we propose a new internal energy estimate that drastically reduces the noise. We also present formulas that enable the optimization of the parameters of the harmonic bias potential for optimal convergence. Finally, we discuss the implications of these findings for the computation of free energies in nanocrystal clusters and superlattices.
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Machine learning is increasingly important in microbiology where it is used for tasks such as predicting antibiotic resistance and associating human microbiome features with complex host diseases. The applications in microbiology are quickly expanding and the machine learning tools frequently used in basic and clinical research range from classification and regression to clustering and dimensionality reduction. In this Review, we examine the main machine learning concepts, tasks and applications that are relevant for experimental and clinical microbiologists. We provide the minimal toolbox for a microbiologist to be able to understand, interpret and use machine learning in their experimental and translational activities.
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Aprendizado de Máquina , Microbiota , HumanosRESUMO
Ozark chinquapin (Castanea ozarkensis Ashe) is a forest tree, endemic to the Ozark Mountain region in Eastern United States. Its nutritious nuts were consumed by Native Americans, European settlers, livestock, and wild animals and its wood was an important rot-resistant construction material. Once a significant tree in regional forest communities, the species was nearly eradicated by a chestnut blight caused by Cryphonectria parasitca (Murill) Barr fungus. Some individuals have survived as sprouts from adventitious root buds, but they rarely reach reproductive maturity. While some in situ restoration efforts are underway, the development of a viable ex situ germplasm preservation method is critical to the conservation of this important food-bearing species. Our experiment aimed to develop a cryopreservation method for C. ozarkensis dormant winter buds subjected to eight experimental treatments before desiccation, slow cooling, and storage in liquid nitrogen vapor. The highest post cryogenic viability was 91.2 % for dormant buds pretreated with 0.3 M sucrose for 16 h followed by 0.75 M sucrose for 3 h; this treatment is suggested for cryopreservation of dormant winter buds of Ozark chinquapin germplasm.