Aggregation Architecture Research Articles

Protein Aggregation in a Nutshell: The Splendid Molecular Architecture of the Dreaded Amyloid Fibrils.

The recent high-resolution structures of amyloid fibrils show that the organization of peptide segments into amyloid aggregate architecture is a general process, though the morphology is more complex and intricate than suspected previously. The amyloid fibrils are often cytotoxic, accumulating as intracellular inclusions or extracellular plaques and have the ability to interfere with cellular physiology causing various cellular malfunctions. At the same time, the highly ordered amyloid structures also present an opportunity for nature to store and protect peptide chains under extreme conditions - something that might be used for designing storage, formulation, and delivery of protein medications or for contriving bio-similar materials of great resistance or structure-ordering capacity. Here we summarize amyloid characteristics; discussing the basic morphologies, sequential requirements and 3D-structure that are required for the understanding of this newly (re)discovered protein structure - a prerequisite for developing either inhibitors or promoters of amyloid-forming processes.

Progressively Refined Face Detection Through Semantics-Enriched Representation Learning

Feature pyramids aim to learn multi-scale representations for detecting faces over various scales. However, they often lack adequate context over different scales, especially when there are many tiny faces in the wild. In this paper, we propose an attention-guided semantically enriched feature aggregation framework to learn a feature pyramid with rich semantics at all scales for face detection. Specifically, high-level abstract features are directly integrated into low-level representations by skip connections to retain as much semantic as possible. In addition, an attention mechanism is employed as a gate to emphasize relevant features and suppress useless features during feature fusion. Inspired by human visual perception of tiny faces, we specially design a deep progressive refined loss (DPRL) to effectively facilitate feature learning. According to the above principles, we design and investigate various feature pyramid frameworks through extensive experiments. Finally, two typical structures named Centralized Attention Feature (CAF) and Distributed Attention Feature (DAF) are proposed for face detection, which are in-place and end-to-end trainable. Extensive experiments across different aggregation architectures on four challenging face detection benchmarks demonstrate the superiority of our framework over state-of-the-art methods.

Recent advances in photofunctional polymorphs of molecular materials

Recently, molecule-based luminescent materials have been drawing extensive attention due to their desirable properties and promising applications in the fields of sensors, lighting display, and cell imaging. Crystalline polymorph is an intriguing phenomenon that the presence of multiple packing and aggregate architectures of the same molecular system. The studies on polymorphs for molecule-based fluorophores provide the opportunities to adjust the mode of molecular packing and photophysical properties, which will help to illustrate the structure-property relationship. In this review, we focus on the recent progress in various feasible methods of molecule-based crystalline polymorphism growth and their adjustable photofunctional properties, which will open up possibilities of variant optical applications. Firstly, several effective ways to prepare and screen polymorphs are sorted out. And then, we discuss the discrepant properties and multifunctional applications (such as sensors, laser, and OFET, etc.). Finally, the development trends and future prospects of these polymorphs are also briefly introduced.

Histomorphological Effects of Aqueous Leaf Extract of Tefairia occidentalis On the Liver of Wistar Rats.

Aim: Telfairia occidentalis has been reported to possess numerous health benefits. This study assessed the histomorphological effect of aqueous leaf extract of Tefairia occidentalis on the liver architecture of wistar rats. Methodology: Sixteen adult female rats weighing between 140-240g were divided into four groups (I-IV) comprising of four (4) rats each. Group I, the control, was given normal rat feed with water, while group II, III, and IV were administered with 150mg/kg, 300mg/kg and 600mg/kg body weight of aqueous leaf extract of Telfairia occidentalis orally respectively via intubation method for 28 days. Thereafter, the experimental animals were sacrificed and their respective liver harvested for histomorphological examination using haematoxylin and eosin (H and E) standard laboratory method. Results: Results showed that there was a significant decrease in the relative weight of the liver in groups II-IV when compared to group I respectively (p<0.05). Photomicrographic section of the liver showed normal hepatic tissue architecture with central vain (CV), portal triad (PT) and hepatocyte (H) in the control animals while photomicrograph section of the liver administered with 150mg/kg aqueous extract of Telfairia occidentalis showed hepatic tissue with focal aggregate inflammatory cell (FAIC) and normal tissue architecture with portal triad (PT) but photomicrograph of liver administered with 300mg/kg and 600mg/kg aqueous extract of Telfairia occidentalis showed alterations. Conclusion: This study revealed that the aqueous leaf extracts of Telfairia occidentalis may possess hepatoprotective effects although it may enhance some physiological changes such as mild hemolysis, infiltration of some inflammatory cells and intra-hepatic hemorrhage detected in this study. Key Words: liver, histomorphology, Telfairia occidentalis, weight, hepatoprotective effect.

Nanofiltration membranes consisting of quaternized polyelectrolyte complex nanoparticles for heavy metal removal

Polyelectrolyte complex nanoparticles (PEC NPs) armed with tunable quaternary ammonium groups are designed from dextran sulfate sodium and chitosan (CS), and utilized as novel building blocks to prepare quaternized polyelectrolyte complex membranes (QPECMs) for nanofiltration process via surface coating and glutaraldehyde crosslinking method. Structural characteristics, surface properties and separation performance of QPECMs are compared with these of quaternized CS membrane (QCSM) and nascent PEC NPs membrane (PECM). Results indicate that increased water permeability of QPECMs generates from loose aggregation architecture moderating tight packing of polymeric chains, while enhanced ion selectivity is attributed to efficient charge character providing strong electrostatic repulsion toward metal cations. Moreover, QPECM-4 features efficient anti-scaling properties with low flux decline ratio of 11.5% and high recovery ratio of 96.5%, accompanied with long-term stability and recyclability in gypsum dynamic filtration. This design strategy of water-soluble PEC NPs serving as building blocks presents facile adaptability to other polyelectrolyte complex membrane systems for specific water treatment and environmental remediation.

Compaction-induced restructuring of aggregated nanoparticle films using the discrete element method

Aggregated nanoparticle films find application in many fields such as gas sensing, solar cells and batteries. These films are characterized by size distributions of polydisperse primary particles and sintered particle aggregates that dictate both the response to external load and functional properties such as heat or charge transport. Mechanical compaction of the films strongly affects these properties in a way that can be quantified by the change of porosity and pore size distributions on the applied compacting pressure. The exact restructuring mechanisms of the aggregate architecture, however, remain unknown. Here, we apply Discrete Element Method (DEM) simulations to gain access to such restructuring mechanisms in TiO2 nanoparticle films synthesized by flame-spray pyrolysis. The ability of the sintered TiO2 aggregates to rearrange via mutual detachment, rolling or sliding events dictated by non-covalent, humidity-dependent interactions are known to be crucial to predict the correct response to compaction. In this work, the importance of elastic deformation of aggregates according to a novel sinter bridge model is elucidated. The best match between DEM simulations and experiments is obtained for bridges with a tensile and bending strengths substantially larger than bulk TiO2, consistently with a low probability of critical fracture initiation in nanometer-scale structures.

Do CHANGE platform: A service-based architecture for secure aggregation and distribution of health and wellbeing data

Over the last decade, the adoption of open API standards offers new services meaningful in the domain of health informatics and behavior change. We present our privacy-oriented solution to support personal data collection, distribution, and usage. Given the new General Data Protection Regulations in Europe, the proposed platform is designed with requirements in mind to position citizens as the controllers of their data. The proposed result uses NodeJS servers, OAuth protocol for Authentication and Authorization, a publish-subscribe semantic for real-time data notification and Cron for APIs without a notification strategy. It uses Distributed Data Protocol to control and securely provision data to distributed frameworks utilizing the data and those distributed applications are exemplified. The platform design is transparent and modularized for research projects and small businesses to set-up and manage, and to allow them to focus on the application layer utilizing personal information. This solution can easily be configured to support custom or new data sources with open API and can scale. In our use cases, maintaining the separate ecosystem services was trivial. The adopted distributed protocol was the most challenging to manage due to its high RAM usage. And implementing a fine-grained privacy control by end-users was challenging in an existing clinical enterprise system.

Options to streamline and enrich biodiversity data aggregation

The success of Darwin Core and ABCD Schema as flexible standards for sharing specimen data and species occurrence records has enabled GBIF to aggregate around one billion data records. At the same time, other thematic, national or regional aggregators have developed a wide range of other data indexes and portals, many of which enrich the data by interpreting and normalising elements not currently handled by GBIF or by linking other data from geospatial layers, trait databases, etc. Unfortunately, although each of these aggregators has specific strengths and supports particular audiences, this diversification produces many weaknesses and deficiencies for data publishers and for data users, including: incomplete and inconsistent inclusion of relevant datasets; proliferation of record identifiers; inconsistent and bespoke workflows to interpret and standardise data; absence of any shared basis for linked open data and annotations; divergent data formats and APIs; lack of clarity around provenance and impact; etc. The time is ripe for the global community to review these processes. From a technical standpoint, it would be feasible to develop a shared, integrated pipeline which harvested, validated and normalised all relevant biodiversity data records on behalf of all stakeholders. Such a system could build on TDWG expertise to standardise data checks and all stages in data transformation. It could incorporate a modular structure that allowed thematic, national or regional networks to generate additional data elements appropriate to the needs of their users, but for all of these elements to remain part of a single record with a single identifier, facilitating a much more rigorous approach to linked open data. Most of the other issues we currently face around fitness-for-use, predictability and repeatability, transparency and provenance could be supported much more readily under such a model. The key challenges that would need to be overcome would be around social factors, particularly to deliver a flexible and appropriate governance model and to allow research networks, national agencies, etc. to embed modular components within a shared workflow. Given the urgent need to improve data management to support Essential Biodiversity Variables and to deliver an effective global virtual natural history collection, we should review these challenges and seek to establish a data management and aggregation architecture that will support us for the coming decades.

Expanded Theory of H- and J-Molecular Aggregates: The Effects of Vibronic Coupling and Intermolecular Charge Transfer.

The electronic excited states of molecular aggregates and their photophysical signatures have long fascinated spectroscopists and theoreticians alike since the advent of Frenkel exciton theory almost 90 years ago. The influence of molecular packing on basic optical probes like absorption and photoluminescence was originally worked out by Kasha for aggregates dominated by Coulombic intermolecular interactions, eventually leading to the classification of J- and H-aggregates. This review outlines advances made in understanding the relationship between aggregate structure and photophysics when vibronic coupling and intermolecular charge transfer are incorporated. An assortment of packing geometries is considered from the humble molecular dimer to more exotic structures including linear and bent aggregates, two-dimensional herringbone and "HJ" aggregates, and chiral aggregates. The interplay between long-range Coulomb coupling and short-range charge-transfer-mediated coupling strongly depends on the aggregate architecture leading to a wide array of photophysical behaviors.

Data Aggregation in Smart Grid AMI Network for Secure Transfer of Energy User-Consumption Data

In a secured smart grid AMI environment, congestion management during data aggregation with security encryption for privacy preservation is a challenging issue. By introducing data communication network schemes into the Advanced Metering Infrastructure (AMI), network traffic congestion and service rates can be improved while preserving user’s privacy from the grid operator’s end. In this paper, a resilient architecture called Ring Triangulation Communication Architecture (RTCA) for data aggregation and user privacy protection is proposed. To preserve privacy as well as reducing traffic congestion in the architecture, DMF homomorphic encryption algorithms were formulated for local concentrators while using a global concentrator to check for anomalies in the AMI server clusters. With TCP/IP protocol and IEEE 802.11 MAC/PHY on the network, TCP message flooding was contextualized for congestion scenario. Stochastic TCP congestion management schemes with wired equivalent privacy (WEP) and the Data Minimizing Function (DMF) scheme were compared. Our proposed architecture significantly reduced transmission congestion and cryptographic overheads incurred during message aggregation. The results of the performance of the DMF Homomorphic encryption scheme incorporated into our proposed architecture for the SG AMI were discussed. These include service rate and other QoS metrics which are negatively affected by a congestive network condition.Keywords: Advanced Metering Infrastructure (AMI), Data Minimizing Function (DMF), Ring Triangulation Communication Architecture (RTCA), Data Aggregation, Smart Grid (SG), Smart Meter (SM).

Molecular and structural architecture of polyQ aggregates in yeast

Huntington's disease is caused by the expansion of a polyglutamine (polyQ) tract in the N-terminal exon of huntingtin (HttEx1), but the cellular mechanisms leading to neurodegeneration remain poorly understood. Here we present in situ structural studies by cryo-electron tomography of an established yeast model system of polyQ toxicity. We find that expression of polyQ-expanded HttEx1 results in the formation of unstructured inclusion bodies and in some cases fibrillar aggregates. This contrasts with recent findings in mammalian cells, where polyQ inclusions were exclusively fibrillar. In yeast, polyQ toxicity correlates with alterations in mitochondrial and lipid droplet morphology, which do not arise from physical interactions with inclusions or fibrils. Quantitative proteomic analysis shows that polyQ aggregates sequester numerous cellular proteins and cause a major change in proteome composition, most significantly in proteins related to energy metabolism. Thus, our data point to a multifaceted toxic gain-of-function of polyQ aggregates, driven by sequestration of endogenous proteins and mitochondrial and lipid droplet dysfunction.

Conformational Dynamics and Stability of U-Shaped and S-Shaped Amyloid β Assemblies.

Alzheimer’s disease is the most fatal neurodegenerative disorder characterized by the aggregation and deposition of Amyloid β (Aβ) oligomers in the brain of patients. Two principal variants of Aβ exist in humans: Aβ1–40 and Aβ1–42. The former is the most abundant in the plaques, while the latter is the most toxic species and forms fibrils more rapidly. Interestingly, fibrils of Aβ1–40 peptides can only assume U-shaped conformations while Aβ1–42 can also arrange as S-shaped three-stranded chains, as recently discovered. As alterations in protein conformational arrangement correlate with cell toxicity and speed of disease progression, it is important to characterize, at molecular level, the conformational dynamics of amyloid fibrils. In this work, Replica Exchange Molecular Dynamics simulations were carried out to compare the conformational dynamics of U-shaped and S-shaped Aβ17–42 small fibrils. Our computational results provide support for the stability of the recently proposed S-shaped model due to the maximized interactions involving the C-terminal residues. On the other hand, the U-shaped motif is characterized by significant distortions resulting in a more disordered assembly. Outcomes of our work suggest that the molecular architecture of the protein aggregates might play a pivotal role in formation and conformational stability of the resulting fibrils.

In Situ Structure of Neuronal C9orf72 Poly-GA Aggregates Reveals Proteasome Recruitment

Protein aggregation and dysfunction of the ubiquitin-proteasome system are hallmarks of many neurodegenerative diseases. Here, we address the elusive link between these phenomena by employing cryo-electron tomography to dissect the molecular architecture of protein aggregates within intact neurons at high resolution. We focus on the poly-Gly-Ala (poly-GA) aggregates resulting from aberrant translation of an expanded GGGGCC repeat in C9orf72, the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. We find that poly-GA aggregates consist of densely packed twisted ribbons that recruit numerous 26S proteasome complexes, while other macromolecules are largely excluded. Proximity to poly-GA ribbons stabilizes a transient substrate-processing conformation of the 26S proteasome, suggesting stalled degradation. Thus, poly-GA aggregates may compromise neuronal proteostasis by driving the accumulation and functional impairment of a large fraction of cellular proteasomes.

Ultrafast Time-Resolved Studies on Fluorescein for Recognition Strands Architecture in Amyloid Fibrils.

Protein aggregation is associated with numerous devastating diseases such as Alzheimer's, Parkinson's, and prion diseases. Development of therapeutics would benefit from knowledge of the structural organization of protein molecules in these amyloid aggregates, particularly in their aqueous biological milieu. However, detailed structural studies to date have been mainly on the solid state and have required large quantities of purified aggregate. Moreover, these conventional methods require the aggregated assembly to remain structurally stable over days or weeks required to perform the experiment, whereas the pathologically relevant species of in vivo aggregates may be shorter lived. Here, we show the organization of protein chains in dissolved amyloid aggregates can be readily determined spectroscopically using minute quantities of fluorescein-labeled protein segments in a matter of minutes. Specifically, we investigated the possibility of using the ultrafast dynamics of fluorescein to distinguish among three categories of β-sheet geometry: (1) antiparallel in-register, (2) parallel in-register, or (3) antiparallel out-of-register. Fluorescein, the most commonly used staining dye in biology and medicine, was covalently attached to the N-termini of peptide sequences selected from a library of known amyloid crystal structures. We investigated the aggregates in solution using steady-state and time-resolved absorption and fluorescence spectroscopy. We found that the dynamics of fluorescein relaxation from the excited state revealed amyloid structure-specific information. Particularly, the nonfluorescent cation form of fluorescein showed remarkable sensitivity to local environments created during aggregation. We demonstrate that time-resolved absorption is capable of differentiating strand organization in β-sheet aggregates when strong intermolecular coupling between chromophores occurs. This approach can be useful in optical recognition of specific fibril architectures of amyloid aggregates.

The NE Atlantic European hake: A neglected high exposure risk for zoonotic parasites in European fish markets

A sampling programme to understand the factors affecting zoonotic parasite presence and infection intensity of Atlantic European hake populations was conducted from 2013 to 2015. Commercial fish samples comprising 430 hake specimens from northern (Grand Sole) and southern (Atlantic Iberian Peninsula) fishing grounds were sampled, recorded and inspected. We also analysed 75 additional samples collected around Scotland. Parasites were microscopically identified to genus level. Fish biometric measurements were statistically evaluated as categorical predictors of parasite recruitment into fish stocks. Stable isotope composition was determined in another sample batch of 501 hakes from the NE Atlantic (Grand Sole and Galician grounds) to explore trophic indicators as potential predictors of parasite burden. Partial sequences from mitochondrial and nuclear marker genes (mtDNA cox2 and EF1 α-1 nDNA) from a set of 915 Anisakis larvae confirmed the northern stock to be parasitized by A. simplex (s.s.) while off the Iberian Peninsula hake there was a mixed infection pattern with larvae of A. simplex s.s. (67.4% of identified larvae), A. pegreffii (31.9%) and the F1hybrid (0.7%). The observed burden of Anisakis spp. larvae differed markedly between fishing areas. The presence of very high Anisakis spp. burdens in a comparatively small proportion of individual fish was well-illustrated with characteristic tensegrity grid architecture for parasite aggregation derived from a plaque-forming cell response observed in the abdominal cavity of larger fish specimens. Demographic infection values were remarkably high in Grand Sole and off the Iberian Peninsula, with 100% prevalence and mean abundances in the fillets ranging from 247 (A. simplex) in hake from Grand Sole to 60 A. simplex and 20 A. pegreffii in southern European populations. Infections were less prevalent and less intense in the hake sample from Scottish waters. Fish size was the most important factor affecting Anisakis spp. prevalence and abundance, with larger fish containing more Anisakis larvae. Anisakis abundance within individual fish was also positively correlated with the condition index although this does not rule out negative effects on the host, and with trophic level, even after fish size was accounted for. These results suggest that higher Anisakis burden is associated with a higher food intake and with eating larger prey. The risk profile for zoonotic parasites herein described for European hake populations underlines the urgent need for adopting a contingency plan that minimizes the risk exposure.

Interoperability, Attribution, and Value in the Web of Natural History Museum Data

Collections, aggregators, collaborative digitization projects, publishers, researchers, and external users are actors in a complex web of biological specimen data interactions, workflows, and pipelines. The software that mediates interactions among these diverse players enables the creation and delivery of species occurrence data from specimens to a growing set of research data consumers. Informaticists have made great strides in developing the individual services, standards and functions; researchers can now almost effortlessly discover and access massive amounts of museum data to address important, integrative science questions. We need to continue to refine individual tools and capabilities that are part of collection data pipelines, and more emphasis is needed on better integration to ensure the automatic transfer of data--enabling museum data pipelines to work with little or no manual intervention. Also, in order for community systems to benefit all parties, specimen data resources not only need to be efficiently aggregated downstream, but 'value adds' need to flow in the reverse direction--upstream to collections, for their benefit, to recognize their role and facilitate their sustainability. There are valuable, un-realized benefits that collections could be accruing from their participation in aggregation architectures and from the subsequent use of their data by researchers. The Biodiversity Collections Network, a US NSF-funded Research Coordination Network project is planning a series of workshops in collaboration with other collections community groups to identify gaps and one-way traps in the collections data pipeline. The meetings will explore pathways for more effective integration and value distribution in the chain that connects collections, aggregators and data consumers. This talk will highlight relevant examples and outline BCoN’s vision in this area.

Fe and C doped TiO2 with different aggregate architecture: Synthesis, optical, spectral and photocatalytic properties, first-principle calculation

Iron and carbon doped nanostructured titanium dioxide with different morphology of aggregates was synthesized using the developed precursor technique. Glycolate of the general composition Ti1-xFex(OCH2CH2O)2-x/2 (0 ≤ x ≤ 0.1) was used as a precursor. The synthesized samples of the compositions Ti1-xFexO2, Ti1-xFexO(2-x/2)-yCy and Ti1-xFexO(2-x/2)-yCy:nC were characterized by X-ray diffraction, scanning electron microscopy, ultraviolet and visible absorption spectroscopy, as well as by vibration and X-ray photoelectron spectroscopy methods. In addition, they were tested as photocatalysts in the hydroquinone oxidation reaction under ultraviolet and visible irradiation. It is established that the insertion of iron into the structure of carbon-doped anatase (TiO2-yCy) suppresses its photocatalytic activity in the visible range of the spectrum, but leads to no change under ultraviolet irradiation. Globular samples of Ti1-xFexO(2-x/2)-yCy containing no more than 2.5 at% Fe show the maximum photocatalytic activity. To clarify the reasons for the observed complex dependence of photocatalytic activity on the concentration of the dopant first-principles, calculations of the electronic band structure and optical absorption of anatase doped with iron and carbon are performed and discussed.

Comparing the Resistance, Resilience, and Stability of Replicate Moving Bed Biofilm and Suspended Growth Combined Nitritation-Anammox Reactors.

Combined partial nitritation-anammox (PN/A) systems are increasingly being employed for sustainable removal of nitrogen from wastewater, but process instabilities present ongoing challenges for practitioners. The goal of this study was to elucidate differences in process stability between PN/A process variations employing two distinct aggregate types: biofilm [in moving bed biofilm reactors (MBBRs)] and suspended growth biomass. Triplicate reactors for each process variation were studied under baseline conditions and in response to a series of transient perturbations. MBBRs displayed elevated NH4+ removal rates relative to those of suspended growth counterparts over six months of unperturbed baseline operation but also exhibited significantly greater variability in performance. Transient perturbations led to strikingly divergent yet reproducible behavior in biofilm versus suspended growth systems. A temperature perturbation prompted a sharp reduction in NH4+ removal rates with no accumulation of NO2- and rapid recovery in MBBRs, compared to a similar reduction in NH4+ removal rates but a high level of accumulation of NO2- in suspended growth reactors. Pulse additions of a nitrification inhibitor (allylthiourea) prompted only moderate declines in performance in suspended growth reactors compared to sharp decreases in NH4+ removal rates in MBBRs. Quantitative fluorescence in situ hybridization demonstrated a significant enrichment of anammox in MBBRs compared to suspended growth reactors, and conversely a proportionally higher AOB abundance in suspended growth reactors. Overall, MBBRs displayed significantly increased susceptibility to transient perturbations employed in this study compared to that of suspended growth counterparts (stability parameter), including significantly longer recovery times (resilience). No significant difference in the maximal impact of perturbations (resistance) was apparent. Taken together, our results suggest that aggregate architecture (biofilm vs suspended growth) in PN/A processes exerts an unexpectedly strong influence on process stability.

MicroThings: A Generic IoT Architecture for Flexible Data Aggregation and Scalable Service Cooperation

The Internet of Things has been widely deployed in various areas of daily life through heterogeneous communications protocols. Each unstandardized protocol focuses on a specific IoT communication pattern. Inspired by the Internet architecture over which divergent devices can easily be accessed and a considerable number of applications can be run, we propose a generic architecture for IoT. This architecture supports two DIY areas: network DIY for data aggregation and application DIY for service cooperation. To connect these two DIYs, a centralized controller has been designed to provide standardized interfaces for data acquisition, organization, and storage, and to support elastic and supportive computing. With these properties, divergent devices can coexist in a uniform microworld, and rich services can be developed and provided on demand to interoperate with physical devices. This article discusses the background, design principles, and advantages of the proposed architecture, as well as open problems and our initial solution, which substantiates a novel IoT architecture and new research ground.

Patterned SLIPS for the Formation of Arrays of Biofilm Microclusters with Defined Geometries.

Biofilms represent an immense problem in medicine due to their strong drug-resistant properties and inherent stress-response activities. Due to the inhomogeneous and very complex architectures of large biofilm aggregates, biofilm studies often suffer from low reproducibility. In this study, an approach to form arrays of homogeneous biofilm microclusters with defined 2D geometries is presented. The method is based on the formation of water-infused hydrophilic porous polymer areas with precise geometries separated by "slippery" lubricant-infused porous surface (SLIPS). Due to the SLIPS' biofilm repellent properties, multiple identical 3D biofilm clusters are formed in the hydrophilic patches that can be used for biofilm screening. Formation of biofilm microcluster arrays of different bacterial strains of Pseudomonas aeruginosa on the SLIPS micropatterns is investigated. Critical parameters influencing minimal adhesive regions for biofilm attachment and minimal SLIPS dimensions to avoid biofilm adhesion are studied. The ability to produce arrays of biofilm microclusters with highly uniform, well-defined shapes opens an opportunity to study interactions of biofilms with various medically relevant factors with a better reproducibility and to investigate the complex biofilm architecture, heterogeneity, and interactions between biofilm subpopulations.