Hydrodynamic and Polyelectrolyte Properties of Actin Filaments: Theory and Experiments

Actin filament′s polyelectrolyte and hydrodynamic properties, their interactions with the biological environment, and external force fields play an essential role in their biological activities in eukaryotic cellular processes. In this article, we introduce a unique approach that combines dynamics and electrophoresis light scattering experiments, an extended semiflexible worm-like chain model, and an asymmetric polymer length distribution theory to characterize the polyelectrolyte and hydrodynamic properties of actin filaments in aqueous electrolyte solutions. We used the same sample and experimental conditions and considered several g-actin and polymerization buffers to elucidate the impact of their chemical composition, reducing agents, pH values, and ionic strengths on the filament translational diffusion coefficient, electrophoretic mobility, structure factor, asymmetric length distribution, effective filament diameter, electric charge, zeta potential, and semiflexibility. Compared to those values obtained from molecular structure models, our results revealed a lower value of the effective G-actin charge and a more significant value of the effective filament diameter due to the formation of the double layer of the electrolyte surrounding the filaments. Additionally, compared to the values usually reported from electron micrographs, the lower values of our results for the persistence length and average contour filament length agrees with the significant difference in the association rates at the filament ends that shift to submicro lengths, the maximum of the length distribution.

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Accompanied versus unaccompanied walking for continuous oxygen saturation measurement during 6-min walk test in COPD: a randomised cross-over study

ERJ Open Research ◽

10.1183/23120541.00921-2020 ◽

2021 ◽

pp. 00921-2020

Author(s):

Thomas F. Riegler ◽

Anja Frei ◽

Sarah R. Haile ◽

Thomas Radtke

Keyword(s):

Oxygen Saturation ◽

Minimal Important Difference ◽

Random Order ◽

Population Level ◽

Walking Distance ◽

Walk Test ◽

Experimental Conditions ◽

Significant Difference ◽

Standardised Testing ◽

The Impact

Study questionIs there i a difference in the 6-Min Walk Test (6 MWT) distance when the assessor accompanies the patient to continuously measure oxygen saturation (SpO2) compared to the patient walking unaccompanied?MethodsWe conducted a prospective randomised cross-over study to evaluate the impact of the assessor walking with the patient during 6 MWT (6 MWTwith) versus patient walking alone (6 MWTwithout). At the end of a pulmonary rehabilitation programme, each patient performed two 6 MWTs in random order and separated by 30 min rest.Results49 COPD patients (GOLD II-IV) were included. In a regression model adjusting for period and subject, accompanying the patient resulted in a lower walking distance (mean difference −9.1 m, [95%CI, −13.9 to −4.3], p=0.0004). Notably, six patients walked more than 30 m further (minimal important difference, MID) in one of the two conditions (6 MWTwith: n=1, 6 MWTwithout: n=5). There were no between-sequence-group differences in heart rate, dyspnoea and leg-fatigue, and SpO2. The median (interquartile range) number and duration of SpO2 signal artefacts were high but not different between the experimental conditions (6 MWTwith: 17 [4, 24], 34 s [7, 113], 6 MWTwithout: 11 [3, 26], 24 s [4, 62]).Answer to the questionOn a study population level, we observed a statistically significant difference in 6 MWT distance between the two experimental conditions, however, the magnitude of difference is small and may not be considered clinically relevant. Nevertheless, in a clinical setting, unaccompanied walking resulted in a substantially higher walking distance pointing towards strictly standardised testing methodology, in particular in pre-post study designs.

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Effects of Fruit Maturity Stages on GC-FID Fatty Acid Profiles, Phenolic Contents, and Biological Activities of Eucalyptus marginata L.

Journal of Food Quality ◽

10.1155/2021/5546969 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Hanene Ghazghazi ◽

Badiaa Essghaier ◽

Ichrak Jawadi ◽

Leila Riahi ◽

Ridha Ben Salem ◽

...

Keyword(s):

Fatty Acid ◽

Biological Activities ◽

Linoleic Acid Content ◽

Maturity Stage ◽

Fatty Acid Profiles ◽

Eucalyptus Marginata ◽

Maturity Stages ◽

Fruit Maturity ◽

Significant Difference ◽

The Impact

The objective of this study was to determine the impact of development stages of Eucalyptus marginata’s fruits on the fatty acid composition as well as on phenolic, flavonoid, and tannin contents of oils. Taking into account fruit maturity stages, vegetable oils have been evaluated for their biological potentials. Fatty acid profiles were quantified using gas chromatography (GC) coupled to a flame ionization detector (FID). The fatty acid profiles of oils obtained from mature fruits showed highest linoleic acid content (49.21%) and Z-vaccenic (C18:1n-7) + oleic (C18:1n-9) acids (22.40%) and a low content of linolenic acid (C18:3) (1.59%). On the other hand, the major saturated fatty acid compound found in the oil of immature Eucalyptus marginata fruits was palmitic acid (C16:0) with about 27%. Based on the Folin–Ciocalteau method, the obtained results revealed a significant difference in the contents of total polyphenols, flavonoids, and tannins according to the stage of fruit maturity ( p < 0.05 ). Furthermore, the detected antimicrobial potentials were related to the fruit maturity stage. While both veg\etable oils extracted from mature and immature Eucalyptus marginata fruits exhibited notable antibacterial activities against the species Staphylococcus aureus, Enterococcus faecalis, Serratia marcescens, and Escherichia coli, only the oils extracted from immature fruits exhibited an antifungal activity against Candida parapsilosis.

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A reformulation of the moderating effects of productive humor

Humor - International Journal of Humor Research ◽

10.1515/humr.14.2.131 ◽

2001 ◽

Vol 14 (2) ◽

Cited By ~ 7

Author(s):

Kerri M Lehman ◽

Kevin L Burke ◽

Randall Martin ◽

Jennifer Sultan ◽

Daniel R Czech

Keyword(s):

Cognitive Task ◽

Small Sample ◽

Stressful Events ◽

Future Research ◽

Anxiety State ◽

Stressful Situation ◽

Experimental Conditions ◽

Significant Difference ◽

Anxiety Levels ◽

The Impact

AbstractThe ability to effectively cope with stress has been demonstrated to be an important factor in warding off potential physical disease and psychological distress. Responses to stressful events have been shown to greatly vary across individuals. Research has shown that intervening variables, such as cognitive appraisals of stressful events, can markedly affect the amount of stress (e.g., mood disturbance, anxiety, changes in neurotransmitter concentrations, suppression of immune system functioning) individuals experience. One such intervening variable, productive humor, was hypothesized to have a positive stress-moderating effect.Four different experimental conditions were used to assess the impact of a stressful situation on mood and anxiety state. Two conditions had subjects produce a humorous narrative in response to the stressful situation. One of these conditions included an instructional video on the use of productive humor. A third condition had subjects produce an intellectual narrative, while a fourth condition had subjects produce no narrative. The humorous narrative conditions were hypothesized to lead to the greatest moderation in stress (i.e., mood and anxiety).In the humorous narrative (without training) condition, subjects who were more successful at producing the narratives showed significantly more moderated changes in mood and anxiety levels pre-task to post-task. These changes were not significantly different from the intellectual or no narrative conditions. The significant difference found between high versus low humorous narrative producers may be accounted for in terms of success versus non-success at completing the experimental task.Finally, among subjects with initially high pre-task mood or anxiety levels and high tendencies to use productive humor, successful performance of some type of a verbal, cognitive task (i.e., humorous or intellectual narrative) was found to be more beneficial in moderating the effects of stress versus silence. These latter findings were based on patterns of results from post hoc analyses with small sample sizes, thus suggesting the need for future research along similar lines.

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The impact of susceptibility correction on diffusion metrics in adolescents

Pediatric Radiology ◽

10.1007/s00247-021-05000-3 ◽

2021 ◽

Author(s):

Katri Lahti ◽

◽

Riitta Parkkola ◽

Päivi Jääsaari ◽

Leena Haataja ◽

...

Keyword(s):

Corpus Callosum ◽

Fractional Anisotropy ◽

Corticospinal Tract ◽

Diffusion Tensor ◽

Length Distribution ◽

Mean Diffusivity ◽

Imaging Method ◽

Brain White Matter ◽

Significant Difference ◽

The Impact

Abstract Background Diffusion tensor imaging is a widely used imaging method of brain white matter, but it is prone to imaging artifacts. The data corrections can affect the measured values. Objective To explore the impact of susceptibility correction on diffusion metrics. Materials and methods A cohort of 27 healthy adolescents (18 boys, 9 girls, mean age 12.7 years) underwent 3-T MRI, and we collected two diffusion data sets (anterior–posterior). The data were processed both with and without susceptibility artifact correction. We derived fractional anisotropy, mean diffusivity and histogram data of fiber length distribution from both the corrected and uncorrected data, which were collected from the corpus callosum, corticospinal tract and cingulum bilaterally. Results Fractional anisotropy and mean diffusivity values significantly differed when comparing the pathways in all measured tracts. The fractional anisotropy values were lower and the mean diffusivity values higher in the susceptibility-corrected data than in the uncorrected data. We found a significant difference in total tract length in the corpus callosum and the corticospinal tract. Conclusion This study indicates that susceptibility correction has a significant effect on measured fractional anisotropy, and on mean diffusivity values and tract lengths. To receive reliable and comparable results, the correction should be used systematically.

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Effect of Bioaugmentation with Anaerobic Fungi Isolated from Ruminants on the Hydrolysis of Corn Silage and Phragmites australis

Applied Sciences ◽

10.3390/app11199123 ◽

2021 ◽

Vol 11 (19) ◽

pp. 9123

Author(s):

Bhargavi Ravi ◽

Valentine Nkongndem Nkemka ◽

Xiying Hao ◽

Jay Yanke ◽

Tim A. McAllister ◽

...

Keyword(s):

Phragmites Australis ◽

Volatile Fatty Acids ◽

Plant Biomass ◽

Biological Activities ◽

Hydrolytic Enzymes ◽

Process Conditions ◽

Anaerobic Fungi ◽

Significant Difference ◽

The Impact ◽

Hydrolysis Of

Anaerobic fungi produce extracellular hydrolytic enzymes that facilitate degradation of cellulose and hemicellulose in ruminants. The purpose of this work was to study the impact of three different anaerobic fungal species (Anaeromyces mucronatus YE505, Neocallimastix frontalis 27, and Piromyces rhizinflatus YM600) on hydrolysis of two different lignocellulosic substrates, corn (Zea mays L.) silage and reed (Phragmites australis (Cav.) Trin. ex Steud.). Biomass from each plant species was incubated anaerobically for 11 days either in the presence of live fungal inoculum or with heat-inactivated (control) inoculum. Headspace gas composition, dry matter loss, soluble chemical oxygen demand, concentration of volatile fatty acids, and chemical composition were measured before and after hydrolysis. While some microbial activity was observed, inoculation with anaerobic fungi did not result in any significant difference in the degradation of either type of plant biomass tested, likely due to low fungal activity or survival under the experimental conditions tested. While the premise of utilizing the unique biological activities of anaerobic fungi for biotechnology applications remains promising, further research on optimizing culturing and process conditions is necessary.

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Measuring Impact of Stress in Sandwich Generation Caring for Demented Parents

GeroPsych ◽

10.1024/1662-9647/a000114 ◽

2014 ◽

Vol 27 (4) ◽

pp. 171-179 ◽

Cited By ~ 6

Author(s):

Laurence M. Solberg ◽

Lauren B. Solberg ◽

Emily N. Peterson

Keyword(s):

Factor Analysis ◽

Exploratory Factor Analysis ◽

Social Worker ◽

Resource Availability ◽

Well Being ◽

Sandwich Generation ◽

Item Questionnaire ◽

Significant Difference ◽

Adult Caregivers ◽

The Impact

Stress in caregivers may affect the healthcare recipients receive. We examined the impact of stress experienced by 45 adult caregivers of their elderly demented parents. The participants completed a 32-item questionnaire about the impact of experienced stress. The questionnaire also asked about interventions that might help to reduce the impact of stress. After exploratory factor analysis, we reduced the 32-item questionnaire to 13 items. Results indicated that caregivers experienced stress, anxiety, and sadness. Also, emotional, but not financial or professional, well-being was significantly impacted. There was no significant difference between the impact of caregiver stress on members from the sandwich generation and those from the nonsandwich generation. Meeting with a social worker for resource availability was identified most frequently as a potentially helpful intervention for coping with the impact of stress.

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Relevance Predictability in Information Retrieval Systems

Methods of Information in Medicine ◽

10.1055/s-0038-1636254 ◽

1967 ◽

Vol 06 (02) ◽

pp. 45-51 ◽

Cited By ~ 6

Author(s):

A. Kent ◽

J. Belzer ◽

M. Kuhfeerst ◽

E. D. Dym ◽

D. L. Shirey ◽

...

Keyword(s):

Information Retrieval ◽

Experimental Conditions ◽

Treatment Groups ◽

Retrieval Systems ◽

Significant Difference ◽

Information Retrieval Systems ◽

High Predictability ◽

Intermediate Response ◽

Quantitative Indicators ◽

Level Of Processing

An experiment is described which attempts to derive quantitative indicators regarding the potential relevance predictability of the intermediate stimuli used to represent documents in information retrieval systems. In effect, since the decision to peruse an entire document is often predicated upon the examination of one »level of processing« of the document (e.g., the citation and/or abstract), it became interesting to analyze the properties of what constitutes »relevance«. However, prior to such an analysis, an even more elementary step had to be made, namely, to determine what portions of a document should be examined.An evaluation of the ability of intermediate response products (IRPs), functioning as cues to the information content of full documents, to predict the relevance determination that would be subsequently made on these documents by motivated users of information retrieval systems, was made under controlled experimental conditions. The hypothesis that there might be other intermediate response products (selected extracts from the document, i.e., first paragraph, last paragraph, and the combination of first and last paragraph), that would be as representative of the full document as the traditional IRPs (citation and abstract) was tested systematically. The results showed that:1. there is no significant difference among the several IRP treatment groups on the number of cue evaluations of relevancy which match the subsequent user relevancy decision on the document;2. first and last paragraph combinations have consistently predicted relevancy to a higher degree than the other IRPs;3. abstracts were undistinguished as predictors; and4. the apparent high predictability rating for citations was not substantive.Some of these results are quite different than would be expected from previous work with unmotivated subjects.

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Implicit and explicit corrective feedback and feedback exposure conditions

Instructed Second Language Acquisition ◽

10.1558/isla.38113 ◽

2020 ◽

Vol 4 (1) ◽

pp. 3-48

Author(s):

Takehiro Iizuka ◽

Kimi Nakatsukasa

Keyword(s):

Explicit Knowledge ◽

Corrective Feedback ◽

Significant Difference ◽

Oral Corrective Feedback ◽

Post Test ◽

Picture Description ◽

Potential Factors ◽

Implicit And Explicit ◽

Instructional Settings ◽

The Impact

This exploratory study examined the impact of implicit and explicit oral corrective feedback (CF) on the development of implicit and explicit knowledge of Japanese locative particles (activity de, movement ni and location ni) for those who directly received CF and those who observed CF in the classroom. Thirty-six college students in a beginning Japanese language course received either recast (implicit), metalinguistic (explicit) or no feedback during an information-gap picture description activity, and completed a timed picture description test (implicit knowledge) and an untimed grammaticality judgement test (explicit knowledge) in a pre-test, immediate post-test and delayed post-test. The results showed that overall there was no significant difference between CF types, and that CF benefited direct and indirect recipients similarly. Potential factors that might influence the effectiveness of CF, such as instructional settings, complexity of target structures and pedagogy styles, are discussed.

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Reducing the Social Stigma Associated with Obsessive Compulsive Disorder: A Controlled Trial of an Intervention Program in a Turkish Community Sample

Journal of Evidence-Based Psychotherapies ◽

10.24193/jebp.2020.2.14 ◽

2020 ◽

Vol 20 (2) ◽

pp. 101-120

Author(s):

Ayça Aktaç Gürbüz ◽

Orçun YORULMAZ ◽

Gülşah DURNA

Keyword(s):

Obsessive Compulsive Disorder ◽

Intervention Program ◽

Controlled Trial ◽

Community Sample ◽

Case Vignette ◽

Control Group ◽

Obsessive Compulsive ◽

Compulsive Disorder ◽

Significant Difference ◽

The Impact

Scientific research into the reduction of stigmatization, particularly related to specific problems such as Obsessive-Compulsive Disorder (OCD), is scarce. In the present study, we examine the impact of a video-based antistigma intervention program for OCD in a pretest-posttest control group research. After being randomly assigned to either an intervention (n= 101) or control group (n= 96), the participants reported their attitudes on a hypothetical case vignette before and after OCD vs. Multiple Sclerosis (MS) videos, and again six months later as a follow up assessment. The mixed design analyses for the group comparisons indicated that although there was no significant difference in the measures of the control group, the participants watching the anti-stigma OCD video, in which the focus was psychoeducation and interaction strategies, reported significantly lower scores on social distances and negative beliefs for the case vignettes they read, and this difference was maintained six months later. Then, the present results indicate the effectiveness of our anti-stigma intervention program for OCD. Interventions to reduce stigmatization can also be viewed as effective tools for changing the attitudes of people toward OCD, although further research and applications are needed related to specific disorders if a longlasting impact is to be achieved.

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Antecedents And Outcomes Of Qwl Among Employees In Banks

Restaurant Business ◽

10.26643/rb.v118i7.7241 ◽

2019 ◽

Vol 118 (7) ◽

pp. 1-19

Author(s):

Geethanjali N ◽

Parveen Roja M ◽

Lavanya D

Keyword(s):

Organizational Climate ◽

Job Stress ◽

Work Life ◽

Working Environment ◽

Quality Of Work Life ◽

Quality Of Work ◽

Significant Difference ◽

Service Productivity ◽

The Impact

Quality of work life is the major factor to be considered in working environment of any organization. The performance of employees and the organization lies on the ability of the employees based on working environment. The QWL leads to better working environment which improves the performance of organization. The present study has made an attempt to find the level of factors causing QWL and the impact of outcome of QWL in banks. Since the profile of the banks may be associated with the level of outcomes of QWL, the present study has made an attempt to examine it with the help of one way analysis of variance and t-test. The included outcomes of QWL are job satisfaction, job stress, organizational climate, organizational commitment, employees retention behaviour, service quality employees and service productivity of employees. The highly associated determinants of QWL and the significant difference among the PUSBs and PRSBs have been noticed. The significantly associating important profiles of the banks regarding the existence of outcome of QWL are identified.

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