Totimorphic assemblies from neutrally stable units.

Inspired by the quest for shape-shifting structures in a range of applications, we show how to create morphable structural materials using a neutrally stable unit cell as a building block. This unit cell is a self-stressed hinged structure with a one-parameter family of morphing motions that are all energetically equivalent. However, unlike kinematic mechanisms, the unit cell is not infinitely floppy and instead exhibits a tunable mechanical response akin to that of an ideal rigid-plastic material. Theory and simulations allow us to explore the properties of planar and spatial assemblies of neutrally stable elements, and solve the inverse problem of designing assemblies that can morph from one given shape into another. Simple experimental prototypes of these assemblies corroborate our theoretical results and show that the addition of switchable hinges allows us to create load-bearing structures. Altogether, totimorphs pave the way for structural materials whose geometry and deformation response can be controlled independently and at multiple scales.

Multiple flat bands and topological Hofstadter butterfly in twisted bilayer graphene close to the second magic angle.

Moiré superlattices in two-dimensional van der Waals heterostructures provide an efficient way to engineer electron band properties. The recent discovery of exotic quantum phases and their interplay in twisted bilayer graphene (tBLG) has made this moiré system one of the most renowned condensed matter platforms. So far studies of tBLG have been mostly focused on the lowest two flat moiré bands at the first magic angle θm1 ∼ 1.1°, leaving high-order moiré bands and magic angles largely unexplored. Here we report an observation of multiple well-isolated flat moiré bands in tBLG close to the second magic angle θm2 ∼ 0.5°, which cannot be explained without considering electron-election interactions. With high magnetic field magnetotransport measurements we further reveal an energetically unbound Hofstadter butterfly spectrum in which continuously extended quantized Landau level gaps cross all trivial band gaps. The connected Hofstadter butterfly strongly evidences the topologically nontrivial textures of the multiple moiré bands. Overall, our work provides a perspective for understanding the quantum phases in tBLG and the fractal Hofstadter spectra of multiple topological bands.

Learning to write with the fluid rope trick.

Direct ink writing, a versatile method of 3D and 4D printing, requires the precise placement of a nozzle just above the print surface to prevent fluid instabilities that cause deviations from the prescribed print path. But what if one could harness the instability associated with the spontaneously folding or coiling of a thin stream of viscous fluid, i.e. use the "fluid rope trick" to write specified patterns on a substrate? Here we use Deep Reinforcement Learning to derive control strategies for the motion of the extruding nozzle and thus the fluid patterns that are deposited on the surface. The method proceeds by having a learner (nozzle) repeatedly interact with the environment (a viscous filament simulator), and improves its strategy using the results of this experience. We demonstrate the outcome of the learned control instructions using experiments to manipulate a falling viscous jet and create cursive writing patterns and Pollockian paintings on substrates.

Study of Thyroid Functions in critically ill Patients admitted in Medical Intensive Care Unit and its Correlation with Critical Care Scoring Acute Physiology and Chronic Health Evaluation III.

BACKGROUND: Thyroid hormones have a crucial role in adapting the metabolic functions during stress and critical illness. Patients who are critically ill may have profound changes in thyroid hormone metabolism. Non-thyroidal Illness Syndrome (NTIS) is one among them, in which there is marked abnormality seen in the thyroid hormone levels. Hence this study is to understand the alterations of the thyroid function tests (TFTs) encountered in critically ill patients admitted in medical intensive care unit (MICU) without primary thyroid disease and to correlate with the severity of Acute Physiology and Chronic Health Evaluation (APACHE III) scoring. METHODS: The study was conducted on 100 critically ill patients with no previous thyroid disorders, admitted in MICU in the Department of General Medicine in a tertiary care hospital between September 2017 and August 2019 who fulfilled the inclusion and exclusion criteria. RESULTS: Out of 100 critically ill patients the abnormal thyroid function prevalence was seen in 78% patients. The most common abnormality seen in our study was low total triiodothyronine (TT3) (61%) followed by low free triiodothyronine (FT3) (36%), low total thyroxine (TT4) (29%), high thyroid-stimulating hormone (TSH) (18%), and low free thyroxine (FT4) (12%). Low TT3, TT4, and FT3 values had a significant correlation with increasing critical severity score of APACHE III with a p value which was statistically significant (p<0.05). CONCLUSIONS: With increase in severity of critical illness assessed by APACHE III, TFT, that is, TT3, TT4, and FT3 levels were decreasing, suggestive of increasing non-thyroidal illness in critically ill patients.

Chitosan and gelatin biopolymer supplemented with mesenchymal stem cells (Velgraft®) enhanced wound healing in goats (Capra hircus): Involvement of VEGF, TGF and CD31.

AIM: Cell-based therapy has emerged as promising strategy for chronic and impaired wounds treatment. Current research is focused on developing biomaterial systems that act as a niche for mesenchymal stem cells (MSCs) to promote wound healing through paracrine molecular cascading. This study was aimed to evaluate the wound healing potential of Velgraft, a ready-to-use biodegradable artificial skin substitute, on excision wound in goats. MATERIALS AND METHODS: Twelve male goats were randomized divided in to three groups of four animals each. After infliction of surgical wound, Velgraft and Soframycin were applied on wounds of the animals of Groups II and III while Group I (sham operated) served as control. Wound diameters were measured at pre-defined time-points for determination of progressive wound healing up to 28 days. Skin sections were stained using Hematoxylin and eosin (H&E) for examining the histoarchitectural changes, Masson trichome staining for ascertaining collagen synthesis and immunohistochemistry for expression of CD31, VEGF and TGF-ß1 proteins to determine post-treatment angiogenesis in the inflicted wounds. RESULTS: Velgraft application appreciably enhanced wound closure by day 21 which was confirmed through restoration of the normal skin architecture as evident based on histopathological examination and characterized by complete regeneration of epidermal layers, collagen fibers, blood capillaries and hair follicular formation. Stimulation of angiogenesis markers was also observed at different time-points post-Velgraft application; which is suggestive of the improved angiogenesis and vasculogenesis. CONCLUSION: Velgraft facilitates wound healing by augmenting early wound closure, enhancing collagen synthesis and deposition, trichosis development and promoting revascularization and epidermal layers restoration.

The time to reversal of complete atrioventricular block and its predictors in acute ST-segment elevation myocardial infarction.

OBJECTIVE: The purpose of this study was to determine the time to reversal of complete AV block (CAVB) in ST-segment elevation myocardial infarction (STEMI) with various modalities of treatment and to examine the factors associated with early reversal of CAVB. METHODS: We prospectively assessed the STEMI patients complicated by CAVB. The mean time to reversal of CAVB was analyzed and compared according to the treatment received. Multivariate logistic regression analysis was performed to find the predictors of mortality. RESULTS: Of 3954 patients with STEMI, CAVB was present in 146(3.7%) patients. Inferior wall myocardial infarction (IWMI) was more commonly associated with CAVB than anterior wall myocardial infarction (AWMI) (74.7% vs 25.3%). The mean time to reversal of CAVB was 25.4 ± 35.5 h. It was significantly lower with the primary percutaneous coronary intervention (PCI) compared to thrombolysis (5.21 ± 10.54 vs 12.98 ± 17.14; p = 0.0001). Predictors of early reversal of CAVB were early presentation to hospital (<6 h) from symptom onset, presence of IWMI, any revascularization done, primary PCI performed in comparison to thrombolysis, and normal serum creatinine levels. The presence of older age, broader QRS complex, cardiogenic shock/heart failure, and elevated creatinine were independent predictors of mortality. The CAVB reverted in all the alive patients except one who required permanent pacemaker implantation. CONCLUSION: CAVB is uncommon in STEMI and it recovers in a vast majority of surviving patients. The time to reversal of CAVB in STEMI is lower with primary PCI compared to thrombolysis. Outcomes are poor without revascularization in such patients.

Blood-pressure Lowering Efficacy and Safety of Perindopril / Indapamide / Amlodipine Single-pill Combination in Hypertensive Patients: Phase III Trial in India.

BACKGROUND: Hypertension is the biggest contributor to global burden of disease and mortality. Increasing compliance with antihypertensive treatment and achieving a wide BP control in the population represents a major challenge for clinical practice. The benefits of single pill combination versus free-equivalent combination has been demonstrated in several meta-analyses and is now strongly supported by the latest 2018 ESC/ESH guidelines. The RAAS blocker with CCB and thiazide like diuretic is proposed as the optimal combination in patients inadequately controlled by two drugs. OBJECTIVE: To assess the blood pressure control rate, safety, tolerability and quality of life with triple-drug SPC in patients with grade II/ III hypertension. METHODS: Hypertensive patients uncontrolled (BP ≥ 140/90 mmHg) on two-drug therapy were recruited in an open-label, phase III clinical trial conducted in outpatient setting in India with 6 months treatment period. No other antihypertensive medication except the study medication was received by the patients. RESULTS: Out of 218 evaluable patients the observed average blood pressure reduction achieved from baseline to end of study at 6 months was Systolic Blood Pressure (SBP) 28.5 mm Hg / Diastolic Blood Pressure (DBP) 13.8 mm Hg. The quality of life (QoL) questionnaire demonstrated improvement in QoL for all patients. CONCLUSION: This study showed the clinical efficacy, safety and acceptability of the perindopril/indapamide/amlodipine SPC in patients with grade 2/3 hypertension inadequately controlled with two-drug therapy. The clinical effectiveness was observed in more than 96 % patients. The benefit of single-pill combination (SPC) therapy in hypertension control was reconfirmed in this study.

Reply to the Letter to Editor Regarding "An Unusual Case of Critical Illness Polyneuromyopathy".

Critical illness myopathy (CIM), critical illness polyneuropathy (CIP), and critical illness polyneuromyopathy (CIPNM) are the group of disorders that are commonly presented as neuromuscular weakness in intensive care unit (ICU) settings. They are responsible for prolonged ICU stay and failure to wean off from mechanical ventilation.1 We report one such case of young female who was admitted with undiagnosed type I diabetes mellitus with diabetic ketoacidosis with severe hypokalemia with sepsis developed acute-onset quadriplegia and diaphragmatic palsy within 72 hours of ICU admission. Detailed investigation led to the diagnosis of critical illness polyneuromyopathy. In view of high morbidity, mortality, and poor prognosis, a guided approach to diagnoses and treatment in earliest possible duration might give better improvement and outcome of the illness. Despite all the odds, our patient showed good clinical improvement and finally got discharged. HOW TO CITE THIS ARTICLE: Mahashabde M, Chaudhary GA, Kanchi G, Rohatgi S, Rao P, Patil R, et al. Reply to the Letter to Editor Regarding "An Unusual Case of Critical Illness Polyneuromyopathy". Indian J Crit Care Med 2020;24(7):604-605.

An Unusual Case of Critical Illness Polyneuromyopathy.

Critical illness myopathy (CIM), critical illness polyneuropathy (CIP), and critical illness polyneuromyopathy (CIPNM) are the group of disorders that are commonly presented as neuromuscular weakness in intensive care unit (ICU) settings. They are responsible for prolonged ICU stay and failure to wean off from mechanical ventilation. We report a case of young female who was admitted with undiagnosed type I diabetes mellitus with diabetic ketoacidosis, severe hypokalemia, sepsis developed acute onset quadriplegia, and diaphragmatic palsy within 72 hours of ICU admission. On detailed investigation, CIPNM was diagnosed. In view of high morbidity, mortality, and poor prognosis, a guided approach to diagnose and treat in earliest possible duration might give better improvement and outcome of the illness. Despite all the odds, our patient showed good clinical improvement and finally got discharged. HOW TO CITE THIS ARTICLE: Mahashabde M, Chaudhary G, Kanchi G, Rohatgi S, Rao P, Patil R, et al. An Unusual Case of Critical Illness Polyneuromyopathy. Indian J Crit Care Med 2020;24(2):133-135.

Linear and nonlinear rheology and structural relaxation in dense glassy and jammed soft repulsive pNIPAM microgel suspensions.

We present an integrated experimental and quantitative theoretical study of the mechanics of self-crosslinked, slightly charged, repulsive pNIPAM microgel suspensions over a very wide range of concentrations (c) that span the fluid, glassy and putative "soft jammed" regimes. In the glassy regime we measure a linear elastic dynamic shear modulus over 3 decades which follows an apparent power law concentration dependence G' ∼ c5.64, a variation that appears distinct from prior studies of crosslinked ionic microgel suspensions. At very high concentrations there is a sharp crossover to a nearly linear growth of the modulus. To theoretically understand these observations, we formulate an approach to address all three regimes within a single conceptual Brownian dynamics framework. A minimalist single particle description is constructed that allows microgel size to vary with concentration due to steric de-swelling effects. Using a Hertzian repulsion interparticle potential and a suite of statistical mechanical theories, quantitative predictions under quiescent conditions of microgel collective structure, dynamic localization length, elastic modulus, and the structural relaxation time are made. Based on a constant inter-particle repulsion strength parameter which is determined by requiring the theory to reproduce the linear elastic shear modulus over the entire concentration regime, we demonstrate good agreement between theory and experiment. Testable predictions are then made. We also measured nonlinear rheological properties with a focus on the yield stress and strain. A theoretical analysis with no adjustable parameters predicts how the quiescent structural relaxation time changes under deformation, and how the yield stress and strain change as a function of concentration. Reasonable agreement with our observations is obtained. To the best of our knowledge, this is the first attempt to quantitatively understand structure, quiescent relaxation and shear elasticity, and nonlinear yielding of dense microgel suspensions using microscopic force based theoretical methods that include activated hopping processes. We expect our approach will be useful for other soft polymeric particle suspensions in the core-shell family.

Syndrome 'Z': A Predictor of Angiographic Severity of Coronary Artery Disease in Patients of Acute Coronary Syndrome.

BACKGROUND: Owing to the growing evidence that the pathophysiology of obstructive sleep apnoea (OSA) and metabolic syndrome (MS) overlap considerably and both adversely impact cardiovascular health, we hypothesised that the presence of OSA with MS additively and adversely affect the severity of coronary artery disease (CAD). Exploration and understanding of this may have direct implications for the development of targeted, preventive strategies for CAD. Thus, this prospective study was aimed to determine the prevalence of 'Syndrome Z' in patients of MS who present with an acute coronary event and to correlate it with the angiographic severity of CAD in these patients. METHODS: The present study was a single centre, cross sectional study conducted in a university teaching hospital. In a span of 6 months, 922 patients with acute coronary syndromes (ACS) were screened for the study. Among these, 861 patients had no evidence of MS. The remaining 61 patients who were diagnosed to have MS were then subjected to an overnight sleep study. Only 58 had good sleep data so were included for further analysis. Angiographic parameters in terms of number of vessels involved and culprit lesions were noted and correlated with presence and absence of OSA and also with its severity based on the Apnoea/Hypopnoea Index (AHI). RESULTS: The prevalence of OSA positivity in patients with MS who presented with ACS was 34.5% (n=20). Most of the patients in the OSA negative group (78.9%, n=30) had disease limited to only one vessel while in the OSA positive group only a minority (15%, n=3) of patients had their disease limited to a single vessel (p=0.001). The number of lesions in the culprit vessel was also significantly less in the OSA negative group compared to the OSA positive group. While in the OSA negative group 68.4% (n=26) patients had a solitary lesion, followed by two and three lesions in 15.8% (n=6) of the patients each, multiple lesions were more common in OSA positive patients, involving 80% of cases (45.0%, n=9 with two lesions; 35.0%, n=7 with three lesions; only 20%, n=4 had a solitary lesion). CONCLUSIONS: Prevalence of 'Syndrome Z' is high in patients having MS presenting with ACS and it correlates with the angiographic severity of CAD.

An Unusual Instigator of Spontaneous Bacterial Peritonitis: Salmonella typhimurium.

Salmonella is an unusual cause of spontaneous bacterial peritonitis (SBP). It is commonly seen in asymptomatic patients with normal or high ascitic fluid protein levels and an immunocompromised state such as AIDS and hematological and solid organ malignancies other than liver. SBP from non-typhoidal Salmonella species should be considered, even in the absence of underlying immunosuppression. Our patient presented with a history of high-grade fever and frequent loose stools with decompensated alcoholic liver cirrhosis. While evaluating the SBP etiology, ascitic fluid turned out positive for the non-typhoidal Salmonella species, which was red, turbid, and hemorrhagic due to portal vein and superior mesenteric vein thrombosis. We thus report an extremely rare case of SBP caused by Salmonella typhimurium in our patient.

Left main coronary artery aneurysm occlusion presenting as myocardial infarction with cardiogenic shock: Patient saved by securing left anterior descending artery at cost the of other vessels.

Coronary artery aneurysms and ST-segment elevation myocardial infarction are rare in clinical practice, presenting a management challenge. To the best of our knowledge, this case appears to be the first successful percutaneous treatment of a completely obstructed aneurysmal left main coronary artery.

Reliability of Fractional Flow Reserve in Non-Infarct-Related Arteries in ST-Segment Elevation Myocardial Infarction Patients Undergoing a Pharmaco-Invasive Approach.

Objectives We investigated the reproducibility of fractional flow reserve (FFR) of significant stenoses (≥70% narrowing) in the non-infarct related artery (NIRA) during the pharmaco-invasive percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI) within 24 hours of thrombolysis and at a follow up of 2-3 weeks. Background STEMI with multivessel disease has worse outcomes. The benefits of FFR-directed PCI of NIRA at the time of primary PCI are yet controversial. Assessing the hemodynamic severity of the NIRA may help in deciding the management strategy of these lesions, save time, and avoid complications. Methods Thirty-one patients undergoing PCI for STEMI under a pharmaco-invasive approach were prospectively recruited. The FFR measurements in 34 stenoses (≥70% diameter stenosis) were obtained immediately after PCI of the culprit stenosis and were repeated at a mean follow-up of 17.6 ± 3.55 (14-21) days. In addition, time to thrombolysis, time from symptom onset to PCI, left ventricular ejection fraction (LVEF), quantitative coronary angiographic measurements of the non-culprit stenoses, and thrombolysis in myocardial infarction (TIMI) flow were recorded. Results There was a significant change in FFR values at follow-up as compared to baseline (0.78 ± 0.08 (0.68-0.93) to 0.77 ± 0.08 (0.67-0.93)) (p = 0.014). In four of the lesions, the FFR values differed by >0.05 at follow-up. The follow-up FFR values led to a change in the management strategy in 5 out of 31 patients (15%) of the lesions. The TIMI flow, percentage diameter stenosis, minimum lumen diameter, and LVEF did not change. There were no predictors of this change in FFR values. Conclusions During the acute phase of STEMI, the severity of non-culprit coronary artery stenoses can not be reliably assessed by FFR. The prolonged jeopardized state of myocardium in pharmaco-invasive PCI as compared to primary PCI seems to be responsible.

Electrical disturbance in heart by smokeless tobacco.

Smokeless tobacco use in the form of chewed tobacco or snuff is common in various parts of the world, including India. It is well known that smokeless tobacco consumption is responsible for cancer but less is known about its role as a risk factor for cardiovascular disease. Nicotine, the main constituent of tobacco smoke is responsible for the elevated risk of the cardiovascular disease and sudden coronary death associated with smoking, presumably by provoking cardiac arrhythmias. This review discusses some of the acute and chronic cardiac effects of smokeless tobacco on cardiovascular disease with special reference to the electrical disturbance as well as comparing nicotine kinetics between smoking and smokeless tobacco. It would further enhance the clamor to urge people to quit all forms of tobacco consumption.

Synconn_build: A python based synthetic dataset generator for testing and validating control-oriented neural networks for building dynamics prediction.

Applying model-based predictive control in buildings requires a control-oriented model capable of learning how various control actions influence building dynamics, such as indoor air temperature and energy use. However, there is currently a shortage of empirical or synthetic datasets with the appropriate features, variability, quality and volume to properly benchmark these control-oriented models. Addressing this need, a flexible, open-source, Python-based tool, synconn_build, capable of generating synthetic building operation data using EnergyPlus as the main building energy simulation engine is introduced. The uniqueness of synconn_build lies in its capability to automate multiple aspects of the simulation process, guided by user inputs drawn from a text-based configuration file. It generates various kinds of unique random signals for control inputs, performs co-simulation to create unique occupancy schedules, and acquires weather data. Additionally, it simplifies the typically tedious and complex task of configuring EnergyPlus files with all user inputs. Unlike other synthetic datasets for building operations, synconn_build offers a user-friendly generator that selectively creates data based on user inputs, preventing overwhelming data overproduction. Instead of emulating the operational schedules of real buildings, synconn_build generates test signals with more frequent variation to cover a broader range of operating conditions. •Synconn_build is an open-source tool designed to address the lack of datasets for benchmarking control-oriented building dynamics prediction models.•The tool automates simulations, data acquisition, and EnergyPlus configuration, guided by user inputs.•Synconn_build prevents data overproduction by selectively creating data, offering a user-friendly approach to dataset generation.

Polar meron-antimeron networks in strained and twisted bilayers.

Out-of-plane polar domain structures have recently been discovered in strained and twisted bilayers of inversion symmetry broken systems such as hexagonal boron nitride. Here we show that this symmetry breaking also gives rise to an in-plane component of polarization, and the form of the total polarization is determined purely from symmetry considerations. The in-plane component of the polarization makes the polar domains in strained and twisted bilayers topologically non-trivial, forming a network of merons and antimerons (half-skyrmions and half-antiskyrmions). For twisted systems, the merons are of Bloch type whereas for strained systems they are of Néel type. We propose that the polar domains in strained or twisted bilayers may serve as a platform for exploring topological physics in layered materials and discuss how control over topological phases and phase transitions may be achieved in such systems.

A tale of two in stent restenosis in same patient: Surprising findings from optical coherence tomography.

Key Clinical Message: The morphology of in-stent restenosis (ISR) in drug eluting stents varies greatly from that of bare metal stents. Optical coherence tomography (OCT) is a useful aid for identifying the nature of ISR and planning the treatment accordingly, which may be by intravascular lithotripsy, cutting balloon or Rotablator, which can be used upfront if OCT shows calcified neoatherosclerosis. Abstract: Restenosis is the decrease in the diameter of the vessel lumen after the performance of percutaneous intervention (PCI), which may or may not involve the implantation of a stent. The morphology of in-stent restenosis (ISR) in drug eluting stents (DES) vary greatly from that of bare metal stents (BMS). We present the case of a 60-years-old lady, who was a follow up case of PCI of the left anterior descending artery with DES and left circumflex artery using BMS 16 years ago. Optical coherence tomography (OCT) revealed both neoatherosclerosis and neointimal hyperplasia in both DES as well as BMS. The morphology of ISR in DES differed from that of BMS. PCI and pharmacological strategies form the main stream of management in case of neointimal hyperplasia. Detection of pattern of ISR on OCT can direct the management of a particular patient, which may be by the use of adjunct devices like intravascular lithotripsy, cutting balloon and Rotablator, which can be used upfront if OCT shows calcified neoatherosclerosis.

Target protein degradation by protacs: A budding cancer treatment strategy.

Cancer is one of the most common causes of death. So, its lethal effect increases with time. Near about hundreds of cancers are known in humans. Cancer treatment is done to cure or prolonged remission, and shrinkage of the tumor. Cytotoxic agents, biological agents/targeted drugs, hormonal drugs, surgery, radiotherapy/proton therapy, chemotherapy, immunotherapy, and gene therapy are currently used in the treatment of cancer but their cost is high and cause various side effects. Seeing this, some new targeted strategies such as PROTACs are the need of the time. Proteolysis targeting chimera (PROTAC) has become one of the most discussed topics regarding cancer treatment. Few of the PROTAC molecules are in the trial phases. PROTACs have many advantages over other strategies such as modularity, compatibility, sub-stoichiometric activity, acting on undruggable targets, molecular design, and acts on intracellular targets, selectivity and specificity can be recruited for any cancer, versatility, and others. PROTACs are having some unclear questions on their pharmacokinetics, heavy-molecular weight, etc. PROTACs are anticipated to bring about a conversion in current healthcare and will emerge as booming treatments. In this review article we summarize PROTACs, their mechanism of action, uses, advantages, disadvantages, challenges, and future aspects for the successful development of potent PROTACs as a drug strategy.

Mechanisms of gill-clogging by hagfish slime.

Hagfishes defend themselves from gill-breathing predators by producing large volumes of fibrous slime when attacked. The slime's effectiveness comes from its ability to clog predators' gills, but the mechanisms by which hagfish slime clogs are uncertain, especially given its remarkably dilute concentration of solids. We quantified the clogging performance of hagfish slime over a range of concentrations, measured the contributions of its mucous and thread components, and measured the effect of turbulent mixing on clogging. To assess the porous structure of hagfish slime, we used a custom device to measure its Darcy permeability. We show that hagfish slime clogs at extremely dilute concentrations like those found in native hagfish slime and displays clogging performance that is superior to three thickening agents. We report an extremely low Darcy permeability for hagfish slime, and an effective pore size of 10-300 nm. We also show that the mucous and thread components play distinct yet crucial roles, with mucus being responsible for effective clogging and low permeability and the threads imparting mechanical strength and retaining clogging function over time. Our results provide new insights into the mechanisms by which hagfish slime clogs gills and may inspire the development of ultra-soft materials with novel properties.