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Objectives: Tai Chi (TC) shows some beneficial effects in reducing pain in knee osteoarthritis (OA). However, the selection of criteria TC forms in previous studies were unclear and inconsistent, possibly accounting for the varying outcomes and rendering the training effects suboptimal. We have selected four optimal TC (OTC) forms based on the knee joint load and its association with pain. This pilot study sought to examine the effect of the OTC forms on reducing knee pain in individuals with knee OA. Methods: Fifteen knee OA participants were recruited. Their knee joint pain level was rated by using the Visual Analogue Scale before and after two weeks of OTC training and compared between these two assessments. Results: The two-week OTC training course was well accepted by our participants. The knee OA pain showed a significant reduction (median pain score: 5 ​cm before training and 1 ​cm post-training, Wilcoxon p ​

Abstract Astronauts experience significant and rapid bone loss as a result of an extended stay in space, making the International Space Station (ISS) the perfect laboratory for studying osteoporosis due to the accelerated nature of bone loss on the ISS. This prompts the question, how does the lack of load due to zero-gravity propagate to bone-forming cells, human fetal osteoblasts (hFOBs), altering their maturation to mineralization? Here, we aim to study the mechanotransduction mechanisms by which bone loss occurs in microgravity. Two automated experiments, microfluidic chips capable of measuring single-cell mechanics via aspiration and cell spheroids incubated in pressure-controlled chambers, were each integrated into a CubeLab deployed to the ISS National Laboratory. For the first experiment, we report protrusion measurements of aspirated cells after exposure to microgravity at the ISS and compare these results to ground control conducted inside the CubeLab. We found slightly elongated protrusions for space samples compared to ground samples indicating softening of hFOB cells in microgravity. In the second experiment, we encapsulated osteoblast spheroids in collagen gel and incubated the samples in pressure-controlled chambers. We found that microgravity significantly reduced filamentous actin levels in the hFOB spheroids. When subjected to pressure, the spheroids exhibited increased pSMAD1/5/9 expression, regardless of the microgravity condition. Moreover, microgravity reduced YAP expression, while pressure increased YAP levels, thus restoring YAP expression for spheroids in microgravity. Our study provides insights into the influence of microgravity on the mechanical properties of bone cells and the impact of compressive pressure on cell signaling in space.

As super-resolution techniques continue to evolve, there is a growing requirement for more advanced methods to capture finer details, particularly when dealing with the smaller pixels within an image. In remote sensing, enhanced spatial details can find utility in diverse applications, such as disaster management, urban planning, and environmental change detection. Many existing image super-resolution algorithms are there to improve image resolution. However, they are not explicitly crafted to accommodate the distinctive attributes of remote-sensing images, rendering them less effective in restoring the details of the images. Therefore, we proposed a convolutional block attention residual network with joint adversarial mechanisms (CRNJAM) to capture finer details in remote sensing images. We first designed a generator based on the residual network and attention mechanism. This has the ability to produce high-quality images with superior resolution, even when the input is of low quality. Then, we train the super-resolved images with high-resolution images with the help of two types of discriminators to generate more realistic images. The first discriminator evaluates an input sample’s local regions or patches. On the other hand, the second discriminator evaluates the entire input sample as a whole. The result shows that the proposed model can significantly reduce the noise in the generated super-resolved image; also, the SR image generated using the proposed method provides competitive advantages over the images generated using other models.

High-resolution remote sensing imagery finds applications in diverse fields, such as land-use mapping, crop planning, and disaster surveillance. To offer detailed and precise insights, reconstructing edges, textures, and other features is crucial. Despite recent advances in detail enhancement through deep learning, disparities between original and reconstructed images persist. To address this challenge, we propose a two-branch multiscale residual attention network for single-image super-resolution reconstruction. The network gathers complex information about input images from two branches with convolution layers of different kernel sizes. The two branches extract both low-level and high-level features from the input image. The network incorporates multiscale efficient channel attention and spatial attention blocks to capture channel and spatial dependencies in the feature maps. This results in more discriminative features and more accurate predictions. Moreover, residual modules with skip connections can help to overcome the vanishing gradient problem. We trained the proposed model on the WHU-RS19 dataset, collated from Google Earth satellite imagery, and validated it on the UC Merced, RSSCN7, AID, and real-world satellite datasets. The experimental results show that our network uses features at different levels of detail more effectively than state-of-the-art models.

The ability of cells to sense and respond to their physical environment plays a fundamental role in a broad spectrum of biological processes. As one of the most essential molecular force sensors and transducers found in cell membranes, mechanosensitive (MS) ion channels can convert mechanical inputs into biochemical or electrical signals to mediate a variety of sensations. The bottom-up construction of cell-sized compartments displaying cell-like organization, behaviors, and complexity, also known as synthetic cells, has gained popularity as an experimental platform to characterize biological functions in isolation. By reconstituting MS channels in the synthetic lipid bilayers, we envision using mechanosensitive synthetic cells for several medical applications. Here, we describe three different concepts for using ultrasound, shear stress, and compressive stress as mechanical stimuli to activate drug release from mechanosensitive synthetic cells for disease treatments.

Abstract The auditory striatum, a sensory portion of the dorsal striatum, plays an essential role in learning and memory. In contrast to its roles and underlying mechanisms in operant conditioning, however, little is known about its contribution to classical auditory fear conditioning. Here, we reveal the function of the auditory striatum in auditory-conditioned fear memory. We find that optogenetically inhibiting auditory striatal neurons impairs fear memory formation, which is mediated through the striatal-amygdala pathway. Using calcium imaging in behaving mice, we find that auditory striatal neuronal responses to conditioned tones potentiate across memory acquisition and expression. Furthermore, nigrostriatal dopaminergic projections plays an important role in modulating conditioning-induced striatal potentiation. Together, these findings demonstrate the existence of a nigro-striatal-amygdala circuit for conditioned fear memory formation and expression.

Abstract Unveiling catalytic mechanisms at a molecular level aids rational catalyst design and selectivity control for process optimization. In this study, we find that the Brønsted acid site density of the zeolite catalyst efficiently controls the guaiacol catalytic pyrolysis mechanism. Guaiacol demethylation to catechol initiates the reaction, as evidenced by the detected methyl radicals. The mechanism branches to form either fulvenone (c-C5H4 = C = O), a reactive ketene intermediate, by catechol dehydration, or phenol by acid-catalyzed dehydroxylation. At high Brønsted acid site density, fulvenone formation is inhibited due to surface coordination configuration of its precursor, catechol. By quantifying reactive intermediates and products utilizing operando photoelectron photoion coincidence spectroscopy, we find evidence that ketene suppression is responsible for the fivefold phenol selectivity increase. Complementary fulvenone reaction pathway calculations, along with 29Si NMR-MAS spectroscopy results corroborate the mechanism. The proposed, flexible operando approach is applicable to a broad variety of heterogeneous catalytic reactions.

The impact of whiting events on global inorganic carbon cycle and climate change is debatable at the current ocean pH. This work engineered whiting events in a high pH, high alkalinity microalgal culture for carbon dioxide capture and storage. When growing the marine microalga Nannochloropsis oceanica IMET1 in photobioreactors, culture alkalinity more than doubled, increasing from 72.5 mg L-1 to a maximum level of 159.6 mg L-1. At the same time, culture pH increased from 7.9 to 10.1 with concomitant calcium carbonate production. X-ray diffraction analysis revealed the precipitated calcium carbonate was primarily monohydrocalcite. The lab culture was scaled up to a 340-L bioreactor, in which Nannochloropsis ash-free dry weight productivities ranged from 25.1 to 51.4 g m-2 d-1 and a maximum monohydrocalcite productivity of 133.4 g m2 d-1 was recorded. In this system, Nannochloropsis biomass contained about 23.9 % lipids and the eicosapentaenoic acid content was about 1.8 %. Together, these results suggest the microalgae-driven calcium carbonate and biomass production process efficiently captures and stores atmospheric carbon dioxide in the form of calcium carbonate while producing valuable bioproducts. Study of the bacterial communities associated with the Nannochloropsis culture identified four dominant species Maricaulis maris, Marinisubtilis pacificus, Gracilimonas sp., and an uncultured bacterium in the OD1 phylum with interesting features that warrant further investigation.

Background One of the most prevalent mental illnesses that chronic kidney disease CKD patients undergoing haemodialysis tend to encounter is depression. Patients receiving haemodialysis have frequently experienced underdiagnosed and undertreated depression.Objectives To assess the mental health of chronic kidney disease patients mainly depression and to analyze reasons for depression among dialysis patients in Gadag district Karnataka.Methods A cross-sectional study was conducted at Government and Private hospitals of Gadag Karnataka between December 2023 to January 2024. Beck Depression Inventory-2 scale was used to assess depression and reasons for depression among CKD patients. Subsequently the statistical analysis of the gathered data was executed using SPSS version 20.0. The predetermined level of statistical significance was established at 5.Results The study included one hundred patients from a district hospital two private hospitals and four subdistrict hospitals. With a mean age of 49.94 years standard deviation 12.85 most of the patients were male 75 with the majority in the age range of 60-69 years 25. Concerningly all the haemodialysis patients suffered from depression in varying severity and as high as 62 patients reported having severe depression. Some of the factors that were found to be associated with depression included religion employment status family income f inancial difficulties fluid intake chronic pain illness that conflicts with living renal diet and sleep disturbance.Conclusion Patients with CKD are more prone to depression and this study also indicates an increased incidence of severe depression among them. The socio-demographic characteristics and factors related to the disease and treatment were associated with the prevalence of depression among the study sample. In order to improve the patientrsquos quality of life depressive symptoms need to be regularly assessed and promptly treated with psychological counselling. The socio-economic causes predisposing to mental health issues need to be addressed as a priority.

Patients face numerous health-related decisions once advanced chronic kidney disease (CKD) is diagnosed. Yet, when patients are underprepared to navigate and discuss health-related decisions, they can make choices inconsistent with their expectations for the future. This pilot study, guided by the multiphase optimization strategy and community-engaged research principles, aimed to explore the acceptability of a developed patient component to a decision-support training intervention called ImPart (Improving Decisional Partnership of CKD Dyads). CKD patients and their family caregivers were recruited from an urban, academic medical center. Eligibility criteria for patients included a diagnosis of stage 3 or higher CKD (on chart review), and caregivers participated in interview sessions only. Patients without a caregiver were not eligible. The intervention was lay coach, telephone-delivered, and designed to be administered in 1-2 week intervals for 4 sessions. An interview guide, developed in collaboration with an advisory group, was designed to ascertain participants' experiences with the intervention. Caregiver interviews focused on changes in the patient's decision ability or engagement. Thirteen patients and eleven caregivers were interviewed. The program was viewed as "good" or "beneficial." Three themes capture the intervention's impact- 1) Frequent and deliberate disease-focused communication, 2) Future planning activation, and 3) Coaching relationship. The piloted intervention was successfully delivered, acceptable to use, and found to promote enhanced disease and future planning communication. By undergoing this work, we ensure that the patient component is feasible to use and meets the needs of participants before implementation in a larger factorial trial.

Fanconi–Bickel syndrome (FBS) is a rare metabolic disorder caused by decreased glucose transporter 2 (GLUT2) function due to several known mutations in the SLC2A2 gene. As of 2020, 144 cases of FBS have been described in the literature. Metabolic and somatic sequelae include dysglycemia and accumulation of glycogen in the kidney and liver. However, there are no descriptions in the literature of possible neuropsychiatric manifestations of FBS. This case report is to our knowledge the first in this regard, describing a patient with FBS who was admitted to our psychiatric inpatient unit while experiencing acute mania. We conceptualize the case as a novel psychiatric presentation of acute mania in FBS, which may inform our understanding of bipolar disorder pathophysiology because of the hypothesized functional changes in neural pathways involving the paraventricular thalamus induced by decreased GLUT2 activity in FBS.

Anaphylaxis is a potentially life-threatening multi-system allergic reaction to a biological trigger resulting in the release of potent inflammatory mediators from mast cells and basophils and causing symptoms in at least two organ systems that generally include skin, lungs, heart, or gastrointestinal tract in any combination. One exception is profound hypotension as an isolated symptom. There are two types of triggers of anaphylaxis: immunologic and non-Immunologic. Immunologic anaphylaxis is initiated when a foreign antigen directly binds to IgE expressed on mast cells or basophils and induces the release of histamine and other inflammatory substances resulting in vasodilation, vascular leakage, decreased peripheral vascular resistance, and heart muscle depression. If left untreated, death by shock (profound hypotension) or asphyxiation (airway obstruction) can occur. The non-immunologic pathway, on the other hand, can be initiated in many ways. A foreign substance can directly bind to receptors of mast cells and basophils leading to degranulation. There can be immune complex activation of the classical complement cascade with the release of anaphylatoxins C3a and C5a with subsequent recruitment of mast cells and basophils. Finally, hyperosmolar contrast agents can cause blood cell lysis, enzyme release, and complement activation, resulting in anaphylactoid (anaphylactic-like) symptoms. In this report we emphasize the recruitment of the bradykinin-forming cascade in mast cell dependent anaphylactic reactions as a potential mediator of severe hypotension, or airway compromise (asthma, laryngeal edema). We also consider airway obstruction due to inhibition of angiotensin converting enzyme with a diminished rate of endogenous bradykinin metabolism, leading not only to laryngeal edema, but massive tongue swelling with aspiration of secretions.

Cells shield organelles and the cytosol via an active boundary predominantly made of phospholipids and membrane proteins, yet allowing communication between the intracellular and extracellular environment. Micron-sized liposome compartments commonly known as giant unilamellar vesicles (GUVs) are used to model the cell membrane and encapsulate biological materials and processes in a cell-like confinement. In the field of bottom-up synthetic biology, many have utilized GUVs as substrates to study various biological processes such as protein-lipid interactions, cytoskeletal assembly, and dynamics of protein synthesis. Like cells, it is ideal that GUVs are also mechanically durable and able to stay intact when the inner and outer environment changes. As a result, studies have demonstrated approaches to tune the mechanical properties of GUVs by modulating membrane composition and lumenal material property. In this context, there have been many different methods developed to test the mechanical properties of GUVs. In this review, we will survey various perturbation techniques employed to mechanically characterize GUVs.

The United States along with the rest of the world has experienced an unprecedented disruption in daily life due to the COVID-19 pandemic. Almost everyone has experienced some sort of stay at home order resulting in an economic catastrophe greater than the Great Recession of 2008 and on par with the Great Depression almost a century ago. Educational institutions at both the K-12 and post-secondary levels have not been immune from the shutdown, with many schools closed from mid-March through the end of the 2020 school year. Many schools moved classes to remote, distance delivery platforms. Career and Technical Education (CTE) teachers were tasked with creative engaging learning activities online for curricula which is taught in a hands-on contextual learning environment. This paper will present preliminary results from research conducted by a collaborative group of nine researchers from across the United States with collectively over 200 years of career and technical education experience. The conceptual framework used for this study was Danielson's Framework for Teaching and Enhancing Professional Practice and Foundations of Career and Technical Education including Constructivism. 3,267 participants representing all 50 states responded to the 37-item survey. The research objectives included description of participants and identified challenges to planning and delivery of CTE content when schools were closed, and instruction was moved to remote/distance/online platforms. Participants ranked their challenges as instructors and their perceptions of challenges that were experienced by their students. CTE teachers ranked replicating classroom or lab environments online and lack of experience teaching online as their biggest challenges. The perceptions of the participants concerning challenges for their students included motivation to guide and manage their own learning and students' access to reliable internet connection. The emergence and prevalence of the COVID-19 pandemic added a layer of complexity to educational practice that was not foreseen and for which no intentional preparation had occurred. Understanding how CTE teachers and instructors responded to this call, and the challenges they and their students encountered, is important to efforts to improve practice in the future and to be in a better position should another crisis occur that forces learning to be delivered in alternative formats from that of the traditional face-to-face classroom. [Note: The page range (177-194) shown on the PDF is incorrect. The correct page range is 177-193.]

When discussing the role of the sacred in design education, the conversation focuses on a transcendent divinity, the dominant paradigm of divinity in the West. This orientation towards a divine other underscores the separateness of rare, specific acts of design-for-the-divine from the majority of the projects students engage in studio and, later, in practice. Of greater value in contemporary classrooms may be student explorations of immanent forms of divinity; of spaces and objects that are not infused with spiritual meaning by their orientation towards some other, higher divinity but by the divinity present within themselves. An immanent orientation in student design studios can add layers of significance to finished projects and overlay the processes of design and production themselves, transforming them from simple acts of production into spiritual acts of communion with the divine. Seeking as a model an extant design culture whose processes and products are intimately interlaced with the immanent-divine, this paper proposes a study of Japanese craft practices and the Japanese native religion of Shinto. Because it emphasizes practice over dogma, vernacular Shinto permeates modern Japanese culture, especially its art and design traditions. From this fusion of Shinto and contemporary Japanese craft, this paper derives three core lessons for Western designers and explores ways of incorporating these lessons into the western design education.

The auditory striatum, the tail portion of dorsal striatum, is implicated in decision-making. This study uncovers a phasic mechanism within the nigrostriatal system that regulates auditory decisions by modulating ongoing auditory perception.

Abstract Slab rollback during subduction plays a key role in controlling continental growth at convergent plate boundaries. The dynamics of currently subducting slabs can be precisely constrained using geophysical techniques. In contrast, ancient episodes of slab rollback can be difficult to constrain, yet are critical to unlocking the tectonic evolution of long‐lived orogens such as the Phanerozoic Australian Tasmanides of eastern Gondwana. Recognition of ancient slab rollback relies on the identification of the progressive migration of magmatic arcs. Here, we investigate the timing and isotopic variation of ∼90 km of the trans‐orogen migration of the Carboniferous Bathurst Batholith as a potential indicator of slab rollback. U–Pb–Hf isotopes, combined with a regional zircon Hf isotope data set, suggest that the eastward migration of the batholith over ∼18 Myr, from 340.1 to 322.4 Ma, records a maximum slab steepening rate of ∼0.6–1.2° Myr−1 in a relatively stable trench setting. These results provide a magmatic record of Carboniferous slab rollback and establish a missing link between the long‐lived Lachlan and New England orogens of the eastern Gondwanan Tasmanides.

Summary: India's woes with an underprioritized and hence underfunded and understaffed public health system continue to plague public healthcare delivery. Though the need for appropriately qualified public health cadre to lead public health programmes is well established, a well-meaning conducive approach to implementing this is lacking. As the COVID-19 pandemic brought back the focus on India's fragmented health system and primary healthcare deficiencies, we discuss the primary healthcare conundrum in India in search of a quintessential fix. We argue for instituting a well-thought and inclusive public health cadre to lead preventive and promotive public health programmes and manage public health delivery. With the aim being to increase community confidence in primary health care, along with the need to augment primary healthcare infrastructure, we argue for a need to augment primary healthcare with physicians trained in family medicine. Provisioning medical officers and general practitioners trained in family medicine can salvage community's confidence in primary care, increase primary healthcare utilization, stymie over-specialization of care, channelize and prioritize referrals, and guarantee competence in healthcare quality for rural communities.

We describe a 28-year-old man who sustained an open IIIB left ankle fracture dislocation with heel pad avulsion. The patient underwent formal angiography of the left lower extremity, followed by free tissue transfer of a rectus abdominis flap several days later. Intraoperatively, a thrombus was identified in the deep inferior epigastric artery above the femoral artery access site requiring thrombectomy. Histologic analysis estimated the thrombus age at 12 to 72 hours, raising concern that the thrombus was induced during angiogram instrumentation. Donor and recipient site-specific risks of arterial instrumentation (including invasive diagnostics) should be considered when planning free tissue transfer.

The newly constructed time-resolved atomic, molecular and optical science instrument (TMO) is configured to take full advantage of both linear accelerators at SLAC National Accelerator Laboratory, the copper accelerator operating at a repetition rate of 120 Hz providing high per-pulse energy as well as the superconducting accelerator operating at a repetition rate of about 1 MHz providing high average intensity. Both accelerators power a soft X-ray free-electron laser with the new variable-gap undulator section. With this flexible light source, TMO supports many experimental techniques not previously available at LCLS and will have two X-ray beam focus spots in line. Thereby, TMO supports atomic, molecular and optical, strong-field and nonlinear science and will also host a designated new dynamic reaction microscope with a sub-micrometer X-ray focus spot. The flexible instrument design is optimized for studying ultrafast electronic and molecular phenomena and can take full advantage of the sub-femtosecond soft X-ray pulse generation program.

Pineapple leaf fibers (PALF) were biopulped using Trametes versicolor, and the resulting biopulp was bleached with xylanase-enzymatic treatments. The biopulping was extensively described using determinations of fiber morphology, color, chemical composition, extractive content, and thermal stability using the structural characteristics determined by XRD and paper properties. The results showed that the chemical and enzymatic treatments shortened the fiber, almost to 50%, and the Kappa index decreased from 27 to 13. Cellulose and holocellulose contents increased from 65% to 74% and from 86% to 91%, respectively, but extractives, lignin (from 12% to 4%), pentosans (from 25% to 14%) and the crystallinity decreased from 58% to 67% in both chemical bleaching and further xylanase-enzymatic processing. Xylanase-enzymatic processing allowed us to obtain whiter (increased lightness color and decreased redness and yellowness tonality) and heavier paper, even though it presented decreased mechanical properties (decreased stress resistance, rupture length, tear resistance and index longitudinal tearing). The xylanase-enzymatic treatment with the best pulping and paper properties is when the biopulp is treated with a xylanase enzyme concentration of 0.04% (w/w).

Abstract TP53 is one of the most frequently altered genes in prostate cancer. The precise assessment of its focal alterations in primary tumors by immunohistochemistry (IHC) has significantly enhanced its prognosis. p53 protein expression and lymphovascular invasion (LVI) were evaluated for predicting metastatic progression by IHC staining of representative whole-mounted prostate sections from a cohort of 189 radical prostatectomy patients with up to 20 years of clinical follow-up. Kaplan–Meier survival curves were used to examine time to distant metastasis (DM) as a function of p53 expression and LVI status. TP53 targeted sequencing was performed in ten tumors with the highest expression of p53 staining. Nearly half (49.8%) of prostate tumors examined showed focal p53 expression while 26.6% showed evidence of LVI. p53(+) tumors had higher pathologic T stage, Grade Group, Nuclear Grade, and more frequent LVI. p53 expression of > 5% and LVI, individually and jointly, are associated with poorer DM-free survival. TP53 mutations were detected in seven of ten tumors sequenced. Four tumors with the highest p53 expression harbored likely pathogenic or pathogenic mutations. High levels of p53 expression suggest the likelihood of pathogenic TP53 alterations and, together with LVI status, could enhance early prognostication of prostate cancer progression.

Online product reviews play a critical role for consumers to make a decision of product purchasing, and become an important data source for vendors to build recommendation systems. Some consumers won’t even buy a product without reading online reviews first, and some vendors invite reviewers to write product reviews before a product is released to the market. However, the review quality could greatly impact the use of the reviews for supporting the purchase decision and recommendation. In order to produce enough high-quality reviews, it is a common practice that vendors provide incentives for writing product reviews. Current research is divided. Some research showed that incentive reviews could be more biased compared to organic reviews, but other scholars showed incentive reviews contain more useful information. Furthermore, other academic publications showed very different results regarding the differences between the incentivized and organic reviews. One of the reasons explaining the observation differences could be due to the quality of the reviewers and reviews. Therefore, it is necessary to control the quality of the reviewers and their reviews for a more objective comparison. In this research, we first discuss an approach for ensuring the quality of the data collection and processing to ensure the quality of the comparison study. Then, we explore the differences between incentivized reviews and organic reviews collected from a website that provides reviews for enterprise software systems. Several parameters of the reviews, such as the overall score, sentiment, and subjectivity of the reviews, were analyzed and compared. Our results could provide a reference for appropriately using reviews and managing the reviewing process.

Abstract Background Uncontrolled growth in solid breast cancer generates mechanical compression that may drive the cancer cells into a more invasive phenotype, but little is known about how such compression affects the key events and corresponding regulatory mechanisms associated with invasion of breast cancer cells including cellular behaviors and matrix degradation. Results Here we show that compression enhanced invasion and matrix degradation of breast cancer cells. We also identified Piezo1 as the putative mechanosensitive cellular component that transmitted compression to not only enhance the invasive phenotype, but also induce calcium influx and downstream Src signaling. Furthermore, we demonstrated that Piezo1 was mainly localized in caveolae, and both Piezo1 expression and compression-enhanced invasive phenotype of the breast cancer cells were reduced when caveolar integrity was compromised by either knocking down caveolin1 expression or depleting cholesterol content. Conclusions Taken together, our data indicate that mechanical compression activates Piezo1 channels to mediate enhanced breast cancer cell invasion, which involves both cellular events and matrix degradation. This may be a critical mechanotransduction pathway during breast cancer metastasis, and thus potentially a novel therapeutic target for the disease.

Investigations of human cardiac disease involving human pluripotent stem cell-derived cardiomyocytes are limited by the disorganized presentation of biomechanical cues resulting in cell immaturity. Here the authors develop a platform of micron-scale 2D cardiac muscle bundles to precisely deliver physiologic cues, improving reproducibility and throughput.

By encapsulating proteins in giant unilamellar vesicles, Bashirzadeh et al find that actin crosslinkers, α-actinin and fascin, can self-assemble with actin into complex structures that depend on the degree of confinement. Further analysis and modeling show that α-actinin and fascin sort to separate domains of these structures. These insights may be generalizable to other biopolymer networks containing crosslinkers.