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2019

Cell and Developmental Biology

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Articles 1 - 24 of 24

Full-Text Articles in Biotechnology

The Antimicrobial Activity And Cellular Targets Of Plant Derived Aldehydes And Degradable Pro-Antimicrobial Networks In Pseudomonas Aeruginosa, Yetunde Adewunmi Dec 2019

The Antimicrobial Activity And Cellular Targets Of Plant Derived Aldehydes And Degradable Pro-Antimicrobial Networks In Pseudomonas Aeruginosa, Yetunde Adewunmi

Dissertations

Essential oils (EOs) are plant-derived products that have been long exploited for their antimicrobial activities in medicine, agriculture, and food preservation. EOs represent a promising alternative to conventional antibiotics due to the broad-range antimicrobial activity, low toxicity to human commensal bacteria, and the capacity to kill microorganisms without promoting resistance. Despite the progress in the understanding of the biological activity of EOs, many aspects of their mode of action remain inconclusive. The overarching aim of this work was to address these gaps by studying molecular interactions between antimicrobial plant aldehydes and the opportunistic human pathogen Pseudomonas aeruginosa. We initiated …


Structural Basis For Chloroperoxidase Catalyzed Enantioselective Epoxidations And Mechanisms Of Selected Anticancer Drug Induced Apoptosis, Yongjian Guo Nov 2019

Structural Basis For Chloroperoxidase Catalyzed Enantioselective Epoxidations And Mechanisms Of Selected Anticancer Drug Induced Apoptosis, Yongjian Guo

FIU Electronic Theses and Dissertations

Chloroperoxidase (CPO), a member of the heme peroxidase family, has diverse catalytic activities toward a broad range of substrates. In addition to catalyzing halogenation reactions involved in the biosynthesis of halogen-containing compounds, CPO also catalyzes reactions typical of traditional heme peroxidases, catalases, and cytochrome P450 enzymes. Despite the powerful and versatile catalytic activity of CPO, its applications have been thwarted by the difficulty in regenerating the active enzyme and substrate (peroxide) induced protein inactivation. To overcome these shorting comings of the protein, we investigate the fabrication and characterization of chloroperoxidase (CPO) and glucose oxidase (GOx) on the surface of MGO. …


The Democratization And Development Of Cell-Free Protein Synthesis, Max Z. Levine Nov 2019

The Democratization And Development Of Cell-Free Protein Synthesis, Max Z. Levine

Master's Theses

Cell-free protein synthesis (CFPS) using crude lysates has developed into a robust platform technology over the last 60 years to express numerous types of recombinant proteins. The open-nature, elimination of reliance on cell viability, and focus of all energy towards production of the protein of interest represent substantial advantages of CFPS over in vivo protein expression methods. CFPS has provided new opportunities across a series of research fields that include metabolic engineering, therapeutic and vaccine development, education, biosensors, and many more. In recent years, optimizations of CFPS have even allowed the platform to reach the industrial level of protein production. …


Updating Molecular Diagnostics For Detecting Methicillin- Susceptible And Methicillin-Resistant Staphylococcus Aureus Isolates In Blood Culture Bottles, Fred C. Tenover, Isabella A. Tickler, Victoria M. Le, Scott Dewell, Rodrigo E. Mendes, Richard V. Goering, Mrsa Consortium Nov 2019

Updating Molecular Diagnostics For Detecting Methicillin- Susceptible And Methicillin-Resistant Staphylococcus Aureus Isolates In Blood Culture Bottles, Fred C. Tenover, Isabella A. Tickler, Victoria M. Le, Scott Dewell, Rodrigo E. Mendes, Richard V. Goering, Mrsa Consortium

Biology Faculty Publications

Molecular diagnostic tests can be used to provide rapid identification of staphylococcal species in blood culture bottles to help improve antimicrobial stewardship. However, alterations in the target nucleic acid sequences of the microorganisms or their antimicrobial resistance genes can lead to false-negative results. We determined the whole-genome sequences of 4 blood culture isolates of Staphylococcus aureus and 2 control organisms to understand the genetic basis of genotypephenotype discrepancies when using the Xpert MRSA/SA BC test (in vitro diagnostic medical device [IVD]). Three methicillin-resistant S. aureus (MRSA) isolates each had a different insertion of a genetic element in the staphylococcal cassette …


Investigating The Role Of Lbh During Early Embryonic Development In Xenopus Laevis, Emma Weir Oct 2019

Investigating The Role Of Lbh During Early Embryonic Development In Xenopus Laevis, Emma Weir

Masters Theses

LBH is a highly conserved protein whose role during vertebrate development is relatively under-studied. In collaboration with the Albertson lab, our lab has previously shown that it is necessary for cranial neural crest cell migration in the zebrafish and in Xenopus laevis. The molecular mechanisms through which it acts are not well understood.

In Xenopus, LBH is a maternally deposited protein. As such, studying its role in early development has not been feasible through the morpholino-mediated knockdown techniques that prevent translation of target genes. Recently, a technique for degrading endogenous proteins was developed, called Trim-Away. This was developed in mammalian …


Total Rna Extraction From Transgenic Flies Misexpressing Foreign Genes To Perform Next Generation Rna Sequencing, Abijeet Singh Mehta, Agustin Luz-Madrigal, Jian-Liang Li, Panagiotis A. Tsonis, Amit Singh Aug 2019

Total Rna Extraction From Transgenic Flies Misexpressing Foreign Genes To Perform Next Generation Rna Sequencing, Abijeet Singh Mehta, Agustin Luz-Madrigal, Jian-Liang Li, Panagiotis A. Tsonis, Amit Singh

Biology Faculty Publications

Due to absence of transgenic approaches in Notopthalmus Viridescens (newt), and conservation of genetic machinery across species, we generated transgenic Drosophila melanogaster to misexpress unique genes from newt. Novel newt genes cloned, and inserted at attP site in Drosophila were misexpressed ubiquitously using tubulin Gal-4. Sample (total RNA) for RNA sequencing was collected at 3rd instar larval stage during which major developmental events takes place in Drosophila. Total RNA was extracted, and purified using RNA clean and ConcentratorTM. RNA quality was quantitated by calculating absorbance at 260 nm (A260) and 280 nm (A280) wavelengths using Nanodrop 2000 spectrophotometer. Good quality …


Comparative Transcriptomic Analysis And Structure Prediction Of Novel Newt Proteins, Abijeet Singh Mehta, Agustin Luz-Madrigal, Jian-Liang Li, Panagiotis A. Tsonis, Amit Singh Aug 2019

Comparative Transcriptomic Analysis And Structure Prediction Of Novel Newt Proteins, Abijeet Singh Mehta, Agustin Luz-Madrigal, Jian-Liang Li, Panagiotis A. Tsonis, Amit Singh

Biology Faculty Publications

Notophthalmus viridescens (Red-spotted Newt) possess amazing capabilities to regenerate their organs and other tissues. Previously, using a de novo assembly of the newt transcriptome combined with proteomic validation, our group identified a novel family of five protein members expressed in adult tissues during regeneration in Notophthalmus viridescens. The presence of a putative signal peptide suggests that all these proteins are secretory in nature. Here we employed iterative threading assembly refinement (I-TASSER) server to generate three-dimensional structure of these novel Newt proteins and predicted their function. Our data suggests that these proteins could act as ion transporters, and be involved …


Assessing The Efficacy Of Seedling Planting As A Forest Restoration Technique In Temperate Hardwood Forests Impacted By Invasive Species, Michaela J. Woods, Meredith Cobb, Katie Hickle Aug 2019

Assessing The Efficacy Of Seedling Planting As A Forest Restoration Technique In Temperate Hardwood Forests Impacted By Invasive Species, Michaela J. Woods, Meredith Cobb, Katie Hickle

Biology Faculty Publications

The emerald ash borer (Agrilus planipennis Fairmaire; EAB) is an invasive insect that causes mortality of trees in the genus Fraxinus, creating canopy gaps that may facilitate invasion by exotic plants. Planting native tree seedlings under EAB-infested Fraxinus may accelerate succession and preclude invasive plant expansion; however, the effectiveness of this approach has not been experimentally tested. We assessed understory seedling planting of Quercus rubra, Carya laciniosa, and Juglans cinerea in EAB-infested forests, where the invasive shrub Lonicera maackii (Amur honeysuckle) was removed. We tested whether the use of plastic tree shelters (“tree tubes”) or planting season (fall versus spring) …


Ipsc Based Gene Correction And Disease Model Of A New Class Of Lgmd Due To Poglut1 Mutation, Jose Ortiz-Vitali Aug 2019

Ipsc Based Gene Correction And Disease Model Of A New Class Of Lgmd Due To Poglut1 Mutation, Jose Ortiz-Vitali

Dissertations & Theses (Open Access)

Recently, a novel class of muscular dystrophy has been discovered in a family due to autosomal recessive missense mutation in POGLUT1. Mutation of this enzyme leads to decreased O-glucosyltransferase activity and impaired Notch signaling, the pathways important for skeletal muscle stem cell (satellite cells) quiescence and activation. We hypothesize that reduced POGLUT1 activity and impaired Notch signaling is causative of this limb girdle muscular dystrophy through dysfunction of muscle stem cells and myogenic progenitors.

To test this, we have used iPSCs for disease modeling and rescue experiments. Using a CRISPR based gene targeting method, we aimed to correct the point …


Emergence Of Oxacillin Resistance In Stealth Methicillin-Resistant Staphylococcus Aureus Due To Meca Sequence Instability, Richard V. Goering, Erin A. Swartzendriber, Anne E. Obradovich, Isabella A. Tickler, Fred C. Tenover Jul 2019

Emergence Of Oxacillin Resistance In Stealth Methicillin-Resistant Staphylococcus Aureus Due To Meca Sequence Instability, Richard V. Goering, Erin A. Swartzendriber, Anne E. Obradovich, Isabella A. Tickler, Fred C. Tenover

Biology Faculty Publications

Staphylococcus aureus strains that possess a mecA gene but are phenotypically susceptible to oxacillin and cefoxitin (OS-MRSA) have been recognized for over a decade and are a challenge for diagnostic laboratories. The mechanisms underlying the discrepancy vary from isolate to isolate. We characterized seven OS-MRSA clinical isolates of six different spa types from six different states by whole-genome sequencing to identify the nucleotide sequence changes leading to the OS-MRSA phenotype. The results demonstrated that oxacillin susceptibility was associated with mutations in regions of nucleotide repeats within mecA. Subinhibitory antibiotic exposure selected for secondary mecA mutations that restored oxacillin resistance. …


Hippo Signaling In Cancer: Lessons From Drosophila Models, Kirti Snigdha, Karishma Sanjay Gangwani, Gauri Vijay Lapalikar, Amit Singh, Madhuri Kango-Singh May 2019

Hippo Signaling In Cancer: Lessons From Drosophila Models, Kirti Snigdha, Karishma Sanjay Gangwani, Gauri Vijay Lapalikar, Amit Singh, Madhuri Kango-Singh

Biology Faculty Publications

Hippo pathway was initially identified through genetic screens for genes regulating organ size in fruitflies. Recent studies have highlighted the role of Hippo signaling as a key regulator of homeostasis, and in tumorigenesis. Hippo pathway is comprised of genes that act as tumor suppressor genes like hippo (hpo) and warts (wts), and oncogenes like yorkie (yki). YAP and TAZ are two related mammalian homologs of Drosophila Yki that act as effectors of the Hippo pathway. Hippo signaling deficiency can cause YAP- or TAZ-dependent oncogene addiction for cancer cells. YAP and TAZ are often activated …


Microrna Profiling And Engineering Of Cho Cell Lines Stably Expressing Difficult-To-Express Lysosomal Protein, Ifeanyi Amadi May 2019

Microrna Profiling And Engineering Of Cho Cell Lines Stably Expressing Difficult-To-Express Lysosomal Protein, Ifeanyi Amadi

KGI Theses and Dissertations

Difficult-to-express (DTE) recombinant proteins like multi-specific proteins, DTE monoclonal antibodies and lysosomal enzymes, have seen difficulties in manufacturability using Chinese hamster ovary (CHO) cells and other mammalian cells as production platforms. CHO cells are preferably used for protein production because of their innate ability to secrete human-like recombinant proteins with post-translational modification, resistance to viral infection and familiarity with drug regulators. However, despite huge progress made in engineering CHO cells for high volumetric productivity, expression of DTE proteins like recombinant lysosomal sulfatase represent one of the poorly understood proteins. Furthermore, there are growing interest in the use of microRNAs (miRNAs) …


Novel Low Shear 3d Bioreactor For The Scaled Production Of High Purity Human Mesenchymal Stem Cells, Andrew Burns May 2019

Novel Low Shear 3d Bioreactor For The Scaled Production Of High Purity Human Mesenchymal Stem Cells, Andrew Burns

KGI Theses and Dissertations

Human mesenchymal stem cells are an ideal candidate for stem cell therapies. They have been researched since the 1960’s and can differentiate into many desired functional cell types without undergoing teratogenesis. However, higher yields are needed for a marketable, successful stem cell therapy. To accomplish this, cells will have to be cultured to expand them to therapeutically relevant dosages for multiple patients. Bioreactor production is an ideal method to solve this problem.

The aim of this thesis is to test and validate a novel bioreactor for the cultivation of human mesenchymal stem cells. In this work, we investigate a novel …


Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi S. Patel May 2019

Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi S. Patel

University Scholar Projects

Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.

Objective: Here, we establish a biodegradable, piezoelectric …


Analyzing The Effect Of Apoptotic Mutations On The State Of The Nascent-Polypeptide Associated Complex In Caenorhabditis Elegans, Monica Gerber May 2019

Analyzing The Effect Of Apoptotic Mutations On The State Of The Nascent-Polypeptide Associated Complex In Caenorhabditis Elegans, Monica Gerber

Senior Honors Projects, 2010-2019

Cells experiencing misfolded protein stress can become debilitated and die, contributing to the onset of disease. The nascent polypeptide-associated complex (NAC) is a heterodimeric translational chaperone that protects against misfolded protein stress by mediating proper protein folding and localization during translation. Depletion of this complex results in misfolded protein accumulation in the endoplasmic reticulum (ER). To determine the importance of the NAC to proteostasis, we have previously depleted the complex in C.elegans via RNA interference and observed numerous dose-dependent effects, including apoptosis of neuronal cells and changes in gene expression of hypodermal cells. While we have observed these cell-specific responses …


Streptococcus Agalactiae Strains With Chromosomal Deletions Evade Detection With Molecular Methods, Isabella A. Tickler, Fred C. Tenover, Scott Dewell, Victoria M. Le, Rachel N. Blackman, Richard V. Goering, Amy E. Rogers, Heather Piwonka, Brittney D. Jung-Hynes, Derrick J. Chen, Michael J. Loeffelholz, Devasena Gnanashanmugam, Ellen Jo Baron Apr 2019

Streptococcus Agalactiae Strains With Chromosomal Deletions Evade Detection With Molecular Methods, Isabella A. Tickler, Fred C. Tenover, Scott Dewell, Victoria M. Le, Rachel N. Blackman, Richard V. Goering, Amy E. Rogers, Heather Piwonka, Brittney D. Jung-Hynes, Derrick J. Chen, Michael J. Loeffelholz, Devasena Gnanashanmugam, Ellen Jo Baron

Biology Faculty Publications

Surveillance of circulating microbial populations is critical for monitoring the performance of a molecular diagnostic test. In this study, we characterized 31 isolates of Streptococcus agalactiae (group B Streptococcus [GBS]) from several geographic locations in the United States and Ireland that contain deletions in or adjacent to the region of the chromosome that encodes the hemolysin gene cfb, the region targeted by the Xpert GBS and GBS LB assays. PCR-negative, culture-positive isolates were recognized during verification studies of the Xpert GBS assay in 12 laboratories between 2012 and 2018. Whole-genome sequencing of 15 GBS isolates from 11 laboratories revealed …


Unified Methods For Feature Selection In Large-Scale Genomic Studies With Censored Survival Outcomes, Lauren Spirko-Burns, Karthik Devarajan Mar 2019

Unified Methods For Feature Selection In Large-Scale Genomic Studies With Censored Survival Outcomes, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

One of the major goals in large-scale genomic studies is to identify genes with a prognostic impact on time-to-event outcomes which provide insight into the disease's process. With rapid developments in high-throughput genomic technologies in the past two decades, the scientific community is able to monitor the expression levels of tens of thousands of genes and proteins resulting in enormous data sets where the number of genomic features is far greater than the number of subjects. Methods based on univariate Cox regression are often used to select genomic features related to survival outcome; however, the Cox model assumes proportional hazards …


Supervised Dimension Reduction For Large-Scale "Omics" Data With Censored Survival Outcomes Under Possible Non-Proportional Hazards, Lauren Spirko-Burns, Karthik Devarajan Mar 2019

Supervised Dimension Reduction For Large-Scale "Omics" Data With Censored Survival Outcomes Under Possible Non-Proportional Hazards, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

The past two decades have witnessed significant advances in high-throughput ``omics" technologies such as genomics, proteomics, metabolomics, transcriptomics and radiomics. These technologies have enabled simultaneous measurement of the expression levels of tens of thousands of features from individual patient samples and have generated enormous amounts of data that require analysis and interpretation. One specific area of interest has been in studying the relationship between these features and patient outcomes, such as overall and recurrence-free survival, with the goal of developing a predictive ``omics" profile. Large-scale studies often suffer from the presence of a large fraction of censored observations and potential …


Diversity Of Resistance Mechanisms In Carbapenem-Resistant Enterobacteriaceae At A Health Care System In Northern California, From 2013 To 2016, Fiona Senchyna, Rajiv L. Gaur, Johanna Sandlund, Cynthia Truong, Guillaume Tremintin, Dietmar Kültz, Carlos A. Gomez, Fiona B. Tamburini, Tessa Andermann, Ami Bhatt, Isabella A. Tickler, Nancy Watz, Indre Budvytiene, Gongyi Shi, Fred C. Tenover, Niaz Banaei Mar 2019

Diversity Of Resistance Mechanisms In Carbapenem-Resistant Enterobacteriaceae At A Health Care System In Northern California, From 2013 To 2016, Fiona Senchyna, Rajiv L. Gaur, Johanna Sandlund, Cynthia Truong, Guillaume Tremintin, Dietmar Kültz, Carlos A. Gomez, Fiona B. Tamburini, Tessa Andermann, Ami Bhatt, Isabella A. Tickler, Nancy Watz, Indre Budvytiene, Gongyi Shi, Fred C. Tenover, Niaz Banaei

Biology Faculty Publications

The mechanism of resistance in carbapenem-resistant Enterobacteriaceae (CRE) has therapeutic implications. We comprehensively characterized emerging mechanisms of resistance in CRE between 2013 and 2016 at a health system in Northern California. A total of 38.7% (24/62) of CRE isolates were carbapenemase gene-positive, comprising 25.0% (6/24) blaOXA-48 like, 20.8% (5/24) blaKPC, 20.8% (5/24) blaNDM, 20.8% (5/24) blaSME, 8.3% (2/24) blaIMP, and 4.2% (1/24) blaVIM. Between carbapenemases and porin loss, the resistance mechanism was identified in 95.2% (59/62) of CRE isolates. Isolates expressing blaKPC were 100% susceptible to ceftazidime–avibactam, meropenem–vaborbactam, …


Identification And Characterization Of Barrier Insulator Activity In The T-Cell Receptor Alpha Locus Control Region, Gayathri Devi Raghupathy Feb 2019

Identification And Characterization Of Barrier Insulator Activity In The T-Cell Receptor Alpha Locus Control Region, Gayathri Devi Raghupathy

Dissertations, Theses, and Capstone Projects

Genes of different spatiotemporal expression profiles are often juxtaposed in the genome. This organization raises risks of cross-regulatory influences from neighboring genes; for instance heterochromatin can spread over euchromatin or long-range acting enhancers can inappropriately activate genes. Gene regulatory elements such as Locus Control Regions (LCR) and Insulators prevent such cross-communications and allow for normal gene expression patterns. In transgenic systems, LCRs limit influences from surrounding chromatin by providing site-of-integration independent and specific spatiotemporal expression upon a linked transgene. The field’s understanding of the ability of an LCR to overcome chromatin influences and allow site-of-integration independent expression is minimal. Interestingly, …


Histology For Cytotechnologists Ii Mls 568, Joanna Burkhardt Jan 2019

Histology For Cytotechnologists Ii Mls 568, Joanna Burkhardt

Library Impact Statements

No abstract provided.


Exploring The Efficacy Of Natural Products In Alleviating Alzheimer’S Disease Using Animal Models, Prajakta Deshpande, Neha Gogia, Amit Singh Jan 2019

Exploring The Efficacy Of Natural Products In Alleviating Alzheimer’S Disease Using Animal Models, Prajakta Deshpande, Neha Gogia, Amit Singh

Biology Faculty Publications

Alzheimer’s disease (hereafter AD) is a progressive neurodegenerative disorder that affects the central nervous system. There are multiple factors that cause AD, viz., accumulation of extracellular Amyloid-beta 42 plaques, intracellular hyper-phosphorylated Tau tangles, generation of reactive oxygen species due to mitochondrial dysfunction and genetic mutations. The plaques and tau tangles trigger aberrant signaling, which eventually cause cell death of the neurons. As a result, there is shrinkage of brain, cognitive defects, behavioral and psychological problems. To date, there is no direct cure for AD. Thus, scientists have been testing various strategies like screening for the small inhibitor molecule library …


Mechanisms And Immunogenicity Of Nspef-Induced Cell Death In B16f10 Melanoma Tumors, Alessandra Rossi, Olga N. Pakhomova, Andrei G. Pakhomov, Samantha Weygandt, Anna A. Bulysheva, Len E. Murray, Peter A. Mollica, Claudia Muratori Jan 2019

Mechanisms And Immunogenicity Of Nspef-Induced Cell Death In B16f10 Melanoma Tumors, Alessandra Rossi, Olga N. Pakhomova, Andrei G. Pakhomov, Samantha Weygandt, Anna A. Bulysheva, Len E. Murray, Peter A. Mollica, Claudia Muratori

Bioelectrics Publications

Accumulating data indicates that some cancer treatments can restore anticancer immunosurveillance through the induction of tumor immunogenic cell death (ICD). Nanosecond pulsed electric fields (nsPEF) have been shown to efficiently ablate melanoma tumors. In this study we investigated the mechanisms and immunogenicity of nsPEF-induced cell death in B16F10 melanoma tumors. Our data show that in vitro nsPEF (20-200, 200-ns pulses, 7 kV/cm, 2 Hz) caused a rapid dose-dependent cell death which was not accompanied by caspase activation or PARP cleavage. The lack of nsPEF-induced apoptosis was confirmed in vivo in B16F10 tumors. NsPEF also failed to trigger ICD-linked responses such …


A 3d Bioprinter Platform For Mechanistic Analysis Of Tumoroids And Chimeric Mammary Organoids, John A. Reid, Xavier-Lewis Palmer, Peter A. Mollica, Nicole Northam, Patrick C. Sachs, Robert D. Bruno Jan 2019

A 3d Bioprinter Platform For Mechanistic Analysis Of Tumoroids And Chimeric Mammary Organoids, John A. Reid, Xavier-Lewis Palmer, Peter A. Mollica, Nicole Northam, Patrick C. Sachs, Robert D. Bruno

Medical Diagnostics & Translational Sciences Faculty Publications

The normal mammary microenvironment can suppress tumorigenesis and redirect cancer cells to adopt a normal mammary epithelial cell fate in vivo. Understanding of this phenomenon offers great promise for novel treatment and detection strategies in cancer, but current model systems make mechanistic insights into the process difficult. We have recently described a low-cost bioprinting platform designed to be accessible for basic cell biology laboratories. Here we report the use of this system for the study of tumorigenesis and microenvironmental redirection of breast cancer cells. We show our bioprinter significantly increases tumoroid formation in 3D collagen gels and allows for precise …