Search results

article

An objective perspective for classic flow classification criteria

Ramon S. Martins, Anselmo Soeiro Pereira, Gilmar Mompean, Laurent Thais, more

Comptes Rendus Mecanique > 2016 > 344 > 1 > 52-59

Four classic criteria used to the classification of complex flows are discussed here. These criteria are useful to identify regions of the flow related to shear, elongation or rigid-body motion. These usual criteria, namely Q, Δ, λ2 and λcr/λci, use the fluid's rate-of-rotation tensor, which is known to vary with respect to a reference frame. The advantages of using objective (invariant with respect...

article

Potassium channels and vascular proliferation

Craig B. Neylon

Vascular Pharmacology > 2002 > 38 > 1 > 35-41

Potassium channels are currently the focus of much attention because of their recently discovered role in the regulation of vascular smooth muscle growth. Dramatic alterations in the expression and activity of K ⁺ channels causing marked changes in the cell's electrical properties accompany enhanced growth of smooth muscle cells (SMCs). These findings indicate that alterations in K ⁺ ...

article

Protein Kinase C in Normal and Pathologic Myocardial States

Brian S. Cain, Daniel R. Meldrum, Alden H. Harken

Journal of Surgical Research > 1999 > 81 > 2 > 249-259

Recent evidence has implicated protein kinase C (PKC) as an important mediator underlying multiple aspects of myocardial function. We and others have recently reported that PKC is involved in Ca ²⁺ -induced inotropy, in mediating myocardial preconditioning by diverse stimuli both in animals and humans, and in the signaling processes which lead to the production of proinflammatory mediators...

article

Direct Effects of Inflammatory Cytokines on Mouse Uterine Contraction

Junjie Bao, Caihan Zhao, Xiaodi Wang, Shiyun Liu, more

American Journal of Reproductive Immunology > 92 > 4 > n/a - n/a

Problem Uterine contractions signal labor onset, with elevated pro‐inflammatory cytokines playing a pivotal role. Prior studies have explored their effects on prostaglandins, oxytocin, and signaling pathways, but have overlooked their direct effects on uterine contractions. Here, we aim to investigate the direct effects of interleukin‐1β (IL‐1β), interleukin‐6 (IL‐6), and tumor necrosis factor‐α...

article

Myosin‐induced F‐actin fragmentation facilitates contraction of actin networks

Kyohei Matsuda, Wonyeong Jung, Yusei Sato, Takuya Kobayashi, more

Cytoskeleton > 81 > 8 > 339 - 355

Mechanical forces play a crucial role in diverse physiological processes, such as cell migration, cytokinesis, and morphogenesis. The actin cytoskeleton generates a large fraction of the mechanical forces via molecular interactions between actin filaments (F‐actins) and myosin motors. Recent studies have shown that the common tendency of actomyosin networks to contract into a smaller structure deeply...

article

Virtual control contraction metrics: Convex nonlinear feedback design via behavioral embedding

Ruigang Wang, Roland Tóth, Patrick J. W. Koelewijn, Ian R. Manchester

International Journal of Robust and Nonlinear Control > 34 > 12 > 7698 - 7721

This article presents a systematic approach to nonlinear state‐feedback control design that has three main advantages: (i) it ensures exponential stability and

ℒ_{2}

‐gain performance with respect to a user‐defined set of reference trajectories, (ii) it provides constructive conditions based on convex optimization and a path‐integral‐based control realization, and (iii) it is less...

article

Extracellular acidification increases uterine contraction in pregnant mouse by increasing intracellular calcium

Asmaa M. Almohanna, Karen Noble, Susan Wray

Acta Physiologica > 240 > 6 > n/a - n/a

Aims As uterine extracellular pH decreases during the ischemic conditions of labor, but its effects on myometrial contraction are largely unknown, there is a need to elucidate its physiological effects and mechanisms of action. Furthermore, it is not known if any of the effects of extracellular acidification are affected by pregnancy, thus we also determined how gestation affects the response to...

article

Electroactive Bi‐Functional Liquid Crystal Elastomer Actuators

Gaoyu Liu, Yakui Deng, Bin Ni, Giao T. M. Nguyen, more

Small > 20 > 12 > n/a - n/a

Liquid crystal elastomers (LCEs) with promising applications in the field of actuators and soft robotics are reported. However, most of them are activated by external heating or light illumination. The examples of electroactive LCEs are still limited; moreover, they are monofunctional with one type of deformation (bending or contraction). Here, the study reports on trilayer electroactive LCE (eLCE)...

article

Beating heart cells: Using cultured cardiomyocytes to study cellular structure and contractility in laboratory exercises

Stephen E. Asmus, Collin K. Wells, Hanna M. Montalvo

Biochemistry and Molecular Biology Education > 51 > 6 > 700 - 707

Heart muscle cells, or cardiomyocytes, exhibit intrinsic contractility in vitro. We found that commercially‐available mammalian cardiomyocytes serve as an excellent model system for studying the cytoskeleton and cellular contractility, fundamental topics in undergraduate cell and molecular biology courses. Embryonic rat cardiomyocytes were plated on cell culture dishes or glass coverslips and visualized...

article

Use of External Uterine Electromyography Across Stage I Labor

Rebecca Benfield, Edward R. Newton

Journal of Midwifery & Women's Health > 68 > 5 > 575 - 580

Introduction Highly sensitive, external uterine electromyography (EMG) measures myometrial electrical activity and is noninvasive compared with the clinical intrauterine pressure catheter. Most experimental studies have measured EMG in 30‐minute epochs, limiting the utility of this instrumentation in intrapartum clinical practice. To test proof of concept, surface uterine EMG contraction activity...

article

Experimental and numerical investigation of scour downstream contracted spillways

Tarek H. Nasralla

Journal of Water and Land Development > 2022 > no. 52 > 53--59

A study of scour downstream of free hydraulic jump in stilling basin of stepped spillways was carried out. This paper employed an experimental study to investigate the stepped spillway with the movable bed material of D₅₀= 3.1 mm. The effect of the contraction ratio of the stepped spillway was highlighted. Different downstream divergent angle was studied to minimise the scour depth, the results showed...

article

Moisture‐Adaptive Contractile Biopolymer‐Derived Fibers for Wound Healing Promotion

Lizhong Dong, Wei Zhang, Ming Ren, Yuxuan Li, more

Small > 19 > 27 > n/a - n/a

The advancement in thermosensitive active hydrogels has opened promising opportunities to dynamic full‐thickness skin wound healing. However, conventional hydrogels lack breathability to avoid wound infection and cannot adapt to wounds with different shapes due to the isotropic contraction. Herein, a moisture‐adaptive fiber that rapidly absorbs wound tissue fluid and produces a large lengthwise contractile...

article

Convergence of the projection and contraction methods for solving bilevel variational inequality problems

Tran Van Thang, Pham Ngoc Anh, Nguyen Duc Truong

Mathematical Methods in the Applied Sciences > 46 > 9 > 10867 - 10885

In this work, we analyze some convergent properties of a projection and contraction algorithm for solving a variational inequality problem, where the feasible domain is the solution set of an affine variational inequality problem. We prove that, for solving the problem where the second cost mapping is affine and not necessary for monotone properties, any iterative sequence generated by the algorithm...

article

¹⁵N‐labeled dietary nitrate supplementation increases human skeletal muscle nitrate concentration and improves muscle torque production

Stefan Kadach, Ji Won Park, Zdravko Stoyanov, Matthew I. Black, more

Acta Physiologica > 237 > 3 > n/a - n/a

Aim Dietary nitrate (NO₃⁻) supplementation increases nitric oxide bioavailability and can enhance exercise performance. We investigated the distribution and metabolic fate of ingested NO₃⁻ at rest and during exercise with a focus on skeletal muscle. Methods In a randomized, crossover study, 10 healthy volunteers consumed 12.8 mmol ¹⁵N‐labeled potassium nitrate (K¹⁵NO₃; NIT) or potassium chloride...

article

Age-related differences in vertical jump height and handgrip strength measurements

Kayla Sisneros, Pratibha Maurya, Evan Johnson, Benton Ford, more

Acta of Bioengineering and Biomechanics > 2023 > Vol. 25, no. 1 > 19--26

This study aimed to examine the effects of age on vertical jump height and handgrip strength measurements in women. A secondary aim was to investigate the correlations between vertical jump height and handgrip strength. Methods: Twenty young (21.5 ± 2.8 years) and twenty older (67.0 ± 5.5 years) healthy women participated in this study. Handgrip contractions were used to assess strength measurements...

article

Kalirin mediates Rac1 activation downstream of calcium/calmodulin‐dependent protein kinase II to stimulate glucose uptake during muscle contraction

Sasa Liu, Rui Qi, Juan Zhang, Chang Zhang, more

FEBS Letters > 596 > 24 > 3159 - 3175

In this study, we investigated the role of calcium/calmodulin‐dependent protein kinase II (CaMKII) in contraction‐stimulated glucose uptake in skeletal muscle. C2C12 myotubes were contracted by electrical pulse stimulation (EPS), and treadmill running was used to exercise mice. The activities of CaMKII, the small G protein Rac1, and the Rac1 effector kinase PAK1 were elevated in muscle by running...

article

Type II achalasia with focal elevated pressures: A distinct manometric and clinical sub‐group

Eric E. Low, Syed Abbas Fehmi, Aws Hasan, Michael Chang, more

Neurogastroenterology & Motility > 34 > 12 > n/a - n/a

Background Type II achalasia (Ach2) is distinguished from other achalasia sub‐types by the presence of panesophageal pressurization (PEP) of ≥30 mmHg in ≥20% swallows on high‐resolution manometry (HRM). Variable manometric features in Ach2 have been observed, characterized by focal elevated pressures (FEPs) (focal/segmental pressures ≥70 mmHg within the PEP band) and/or high compression pressures...

article

Should I stay or should I go: Hydrologic characteristics and body size influence fish emigration from the floodplain following an atypical summer flood

Richard H. Walker, Christopher J. Naus, Steven Reid Adams

Ecology of Freshwater Fish > 31 > 4 > 607 - 621

Floods play an important role in regulating ecological patterns and processes in river–floodplain ecosystems. Yet, the hydrologic connectivity between many river–floodplain ecosystems has been severed by anthropogenic activities that have markedly altered these ecological processes. Superimposed over anthropogenic reductions in river–floodplain connectivity, climate change is also shifting flood characteristics...

article

Impact of obesity on uterine contractile activity during labour: A blinded analysis of a randomised controlled trial cohort

Tuija Hautakangas, Jukka Uotila, Joel Kontiainen, Heini Huhtala, more

BJOG: An International Journal of Obstetrics & Gynaecology > 129 > 10 > 1790 - 1797

Objective To investigate the impact of severe obesity (body mass index [BMI] ≥35 kg/m²) on uterine contractile activity. The hypothesis was that obese parturients might have weaker uterine activity and need more oxytocin than leaner parturients. Design Exploratory, blinded analysis of a randomised controlled trial cohort. Setting Two labour wards, one in a university tertiary hospital and one...

article

Investigation of Effects of Gadolinium‐Based Contrast Agents on Uterine Contractility Using Isolated Rat Myometrium

Gülseren Dinç, Arif K. Salihoğlu, Burak Ozgoren, Selçuk Akkaya, more

Journal of Magnetic Resonance Imaging > 55 > 6 > 1761 - 1770

Background Despite concerns about safety, gadolinium‐based contrast agents (GBCAs) are still used for abdominal and pelvic imaging during pregnancy. Researchers have mainly focused on teratogenicity, while very little is known about their possible direct effects on uterine contractility, yet free gadolinium potentially impacts contractility through interaction with calcium channels. Purpose To...

INFONA - science communication portal

Search results

An objective perspective for classic flow classification criteria

Potassium channels and vascular proliferation

Protein Kinase C in Normal and Pathologic Myocardial States

Direct Effects of Inflammatory Cytokines on Mouse Uterine Contraction

Myosin‐induced F‐actin fragmentation facilitates contraction of actin networks

Virtual control contraction metrics: Convex nonlinear feedback design via behavioral embedding

Extracellular acidification increases uterine contraction in pregnant mouse by increasing intracellular calcium

Electroactive Bi‐Functional Liquid Crystal Elastomer Actuators

Beating heart cells: Using cultured cardiomyocytes to study cellular structure and contractility in laboratory exercises

Use of External Uterine Electromyography Across Stage I Labor

Experimental and numerical investigation of scour downstream contracted spillways

Moisture‐Adaptive Contractile Biopolymer‐Derived Fibers for Wound Healing Promotion

Convergence of the projection and contraction methods for solving bilevel variational inequality problems

¹⁵N‐labeled dietary nitrate supplementation increases human skeletal muscle nitrate concentration and improves muscle torque production

Age-related differences in vertical jump height and handgrip strength measurements

Kalirin mediates Rac1 activation downstream of calcium/calmodulin‐dependent protein kinase II to stimulate glucose uptake during muscle contraction

Type II achalasia with focal elevated pressures: A distinct manometric and clinical sub‐group

Should I stay or should I go: Hydrologic characteristics and body size influence fish emigration from the floodplain following an atypical summer flood

Impact of obesity on uterine contractile activity during labour: A blinded analysis of a randomised controlled trial cohort

Investigation of Effects of Gadolinium‐Based Contrast Agents on Uterine Contractility Using Isolated Rat Myometrium

Filter options

Publication date

Content availability

Publication type

Publication language

Keywords

Data set

INFONA - science communication portal

Search results

Add recipient

Sending message cancelled

Are you sure you want to cancel sending this message?

Send message

Filter options

Publication date

Date range setting

Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.

Content availability

Publication type

Publication language

Keywords

Data set

Reporting an error / abuse

Sending the report failed

Accessibility options