A Statistical Approach to Determine Optimal Models for IUPAC-Classified Adsorption Isotherms

Adsorption heat transformation (AHT) systems can play a major role in protecting our environment by decreasing the usage of fossil fuels and utilizing natural and alternative working fluids. The adsorption isotherm is the most important feature in characterizing an AHT system. There are eight types of International Union of Pure and Applied Chemistry (IUPAC) classified adsorption isotherms for different “adsorbent-adsorbate” pairs with numerous empirical or semi-empirical mathematical models to fit them. Researchers face difficulties in choosing the best isotherm model to describe their experimental findings as there are several models for a single type of adsorption isotherm. This study presents the optimal models for all eight types of isotherms employing several useful statistical approaches such as average error; confidence interval (CI), information criterion (ICs), and proportion tests using bootstrap sampling. Isotherm data of 13 working pairs (which include all eight types of IUPAC isotherms) for AHT applications are extracted from literature and fitted with appropriate models using two error functions. It was found that modified Brunauer–Emmet–Teller (BET) for Type-I(a) and Type-II; Tóth for Type-I(b); GAB for Type-III; Ng et al. model for Type-IV(a) and Type-IV(b); Sun and Chakraborty model for Type-V; and Yahia et al. model for Type-VI are the most appropriate as they ensure less information loss compared to other models. Moreover; the findings are affirmed using selection probability; overall; and pairwise proportion tests. The present findings are important in the rigorous analysis of isotherm data.

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Distinctive attributes for predicted secondary structures at terminal sequences of non-classically secreted proteins from proteobacteria

Open Life Sciences ◽

10.2478/s11535-008-0026-5 ◽

2008 ◽

Vol 3 (3) ◽

pp. 320-326 ◽

Cited By ~ 2

Author(s):

Inara Kampenusa ◽

Peteris Zikmanis

Keyword(s):

Strong Predictor ◽

Property Values ◽

Secondary Structures ◽

Secreted Proteins ◽

Average Error ◽

Type I ◽

Multiple Discriminant Analysis ◽

Type Iv ◽

Secretion Pathways ◽

Leave One Out

AbstractC- and N-terminal sequences (64 amino acid residues each) of 89 non-classically secreted type I, type III and type IV proteins (Swiss-Prot/TrEMBL) from proteobacteria were transformed into predicted secondary structures. Multivariate analysis of variance (MANOVA) confirmed the significance of location (C- or N-termini) and secretion type as essential factors in respect of quantitative representations of structured (a-helices, b-strands) and unstructured (coils) elements. The profiles of secondary structures were transcripted using unequal property values for helices, strands and coils and corresponding numerical vectors (independent variables) were subjected to multiple discriminant analysis with the types of secreted proteins as the dependent variables. The set of strong predictor variables (21 property values located at the region of 2–49 residues from the C-termini) was capable to classify all three types of non-classically secreted proteins with an accuracy of 93.3% for originally and 89.9% for cross-validated (leave-one-out procedure) grouped cases. The average error rate (0.137 ± 0.015) of k-fold (k = 3; 4; 6; 8; 10; 89) cross validation affirmed an acceptable prediction accuracy of defined discriminant functions with regard to the types of non-classically secreted proteins. The proposed prediction tool could be used to specify the secretome proteins from genomic sequences as well as to assess the compatibility between secretion pathways and secretion substrates of proteobacteria.

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Genomic diversity ofmecregulator genes in methicillin-resistantStaphylococcus aureusandStaphylococcus epidermidis

Epidemiology and Infection ◽

10.1017/s0950268800001461 ◽

1996 ◽

Vol 117 (2) ◽

pp. 289-295 ◽

Cited By ~ 16

Author(s):

N. Kobayashi ◽

K. Taniguchi ◽

K. Kojima ◽

S. Urasawa ◽

N. Uehara ◽

...

Keyword(s):

Methicillin Resistance ◽

Polymerase Chain Reaction Amplification ◽

Point Mutations ◽

Genomic Diversity ◽

Single Type ◽

Type I ◽

Type Iv ◽

Gene Type ◽

Regulator Genes ◽

Constitutive Production

SummaryLow-affinity penicillin-binding protein PBP-2a encoded bymecAis closely related to methicillin resistance in staphylococci, and expression of PBP-2a is controlled by regulator elements encoded bymecRlandmecIwhich are located adjacent tomecAon the chromosome. Deletion or mutation which occurred inmecregulator gene is considered to be associated with constitutive production of PBP-2a. The distribution of themecregulator genes in 176 strains ofStaphylococcus aureusand 33 strains ofS. epidermidisisolated from a single hospital was studied by polymerase chain reaction amplification. Most clinical isolates of methicillin-resistantS. aureus(MRSA) (94.3 %) andS. epidermidis(MRSE) (83.9 %) possessed bothmecIandmecR1genes (type I), whereas nomecregulator genes were detected inmecA-negative isolates. In contrast, 7 MRSA and 5 MRSE isolates were found to have incomplete regulator genes, and they were classified into three groups; strains which lacked onlymecIgene (type II), strains which lackedmecIand 3'-end ofmecR1gene (type III), and strains which lacked both regulator genes (type IV). Analysis ofmecIgene from all the strains havingmecIby restriction fragment length polymorphism afterMseI digestion indicated that three MRSA strains possessed one of the known point mutations identified previously. These findings indicated the predominance of a single type of MRSA possessing bothmecIandmecR1in the study period and also suggested a high genomic diversity inmecregulator region of staphylococci.

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The Histology of the Nervous System of an Insect, Rhodnius prolixus (Hemiptera)

Journal of Cell Science ◽

10.1242/jcs.s3-100.50.299 ◽

1959 ◽

Vol s3-100 (50) ◽

pp. 299-313

Author(s):

V. B. WIGGLESWORTH

Keyword(s):

Nervous System ◽

Ganglion Cells ◽

Single Type ◽

Type I ◽

Ethyl Gallate ◽

Motor Axons ◽

Type Iv ◽

Lateral Group ◽

Medial Group ◽

Large Motor

The central nervous system of Rhodnius has been studied in sections stained with osmium/ethyl gallate. The single type of glial cell responsible for perineurium and axon sheaths in the peripheral nerves becomes differentiated in the thoracic ganglia into four types. Type i cells form the layer of perineurium cells filled with filamentous mitochondria. These cells which are rich in succinoxidase control the passage of all substances to and from the ganglion. Type ii cells produce the thick myelin-type sheaths for the lateral group of motor axons (see below). Type iii cells, the giant glial cells in the ganglionic layer, have a very extensive cytoplasm which sends deep tongue-like invaginations into the large ganglion cells. This cytoplasm must control the transmission of nutrients and excretory substances to and from the neurones. It contains some non-specific esterase. Type iv cells form an investment of the neuropile. They also have extensive cytoplasm which surrounds the axons and dendrites and provides intensely staining inter-neuronal material in the synaptic regions. This material, the ‘darkly staining neuropile’, is the chief site of acetylcholine esterase. The nerve-tracts are well displayed by the osmium / ethyl gallate method. The axons appear as unstained cords containing mitochondria, against the dark neuropile. The large motor axons of the legs separate into two groups. The medial group run directly into the neuropile and have thin sheaths. The lateral group remain outside the neuropile; they become narrow and enclosed in a thick myelin-type sheath; but as they turn into the neuropile the sheath becomes thin and the axons enlarge again.

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Study on Optimum IUPAC Adsorption Isotherm Models Employing Sensitivity of Parameters for Rigorous Adsorption System Performance Evaluation

Energies ◽

10.3390/en14227478 ◽

2021 ◽

Vol 14 (22) ◽

pp. 7478

Author(s):

Md. Matiar Rahman ◽

Abu Zar Shafiullah ◽

Animesh Pal ◽

Md. Amirul Islam ◽

Israt Jahan ◽

...

Keyword(s):

Experimental Data ◽

Adsorption Isotherm ◽

Transformation Method ◽

Precise Determination ◽

Isotherm Model ◽

Isotherm Models ◽

Low Grade ◽

Type I ◽

Type Iv ◽

Significant Difference

Adsorption cooling technologies driven by low-grade thermal or solar power are used as an energy-efficient alternative to conventional refrigeration and air conditioning systems. Explicit understanding of the adsorption cycles requires precise determination of the performance parameters, replication of the experimental data, and the rigorous study of the adsorption heat transformation method. Hence, the optimum adsorption isotherms model must be identified. Scientists often face difficulties in selecting the suitable isotherm model as there are many models for a particular form of adsorption isotherm. The present study introduces a novel approach for choosing the optimal models for each type of International Union of Pure and Applied Chemistry (IUPAC) classified adsorption isotherm using robust statistical methods. First, the box-and-whisker plots of error identification are employed. Tóth for Type-I(a) and Type-I(b), modified BET for Type-II, GAB for Type-III, Universal for Type-IV(a), and Type-IV(b), Sun Chakrabarty for Type-V, and Yahia et al. for Type-VI were found lower than the other candidate models in box-and-whisker plot. The optimality of our selected models was further verified using analysis of variance (ANOVA), pairwise Tukey honest significant difference (HSD) test, Kruskal–Wallis rank-sum test, and pairwise Wilcoxon rank-sum test. In short, rigorous statistical analysis was performed to identify the best model for each type of isotherm by minimizing error. Moreover, specific cooling effect (SCE) of Maxsorb III/ethanol and silica gel/water pairs were determined. Results showed that Tóth is the optimal isotherm model for the studied pairs, and the SCE values obtained from the model agree well with experimental data. The optimum isotherm model is indispensable for the precise designing of the next generation adsorption cooling cycles.

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Labelling of non-A, non-B hepatitis infected chimpanzee hepatocytes with nuclease-gold conjugates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111367 ◽

1984 ◽

Vol 42 ◽

pp. 250-251

Author(s):

G. D. Gagne ◽

M. F. Miller ◽

D. A. Peterson

Keyword(s):

Endoplasmic Reticulum ◽

Experimental Infection ◽

Uranyl Acetate ◽

Type I ◽

Cellular Injury ◽

Type Ii ◽

Tubular Structures ◽

Type Iii ◽

Type Iv ◽

Infected Chimpanzee

Experimental infection of chimpanzees with non-A, non-B hepatitis (NANB) or with delta agent hepatitis results in the appearance of characteristic cytoplasmic alterations in the hepatocytes. These alterations include spongelike inclusions (Type I), attached convoluted membranes (Type II), tubular structures (Type III), and microtubular aggregates (Type IV) (Fig. 1). Type I, II and III structures are, by association, believed to be derived from endoplasmic reticulum and may be morphogenetically related. Type IV structures are generally observed free in the cytoplasm but sometimes in the vicinity of type III structures. It is not known whether these structures are somehow involved in the replication and/or assembly of the putative NANB virus or whether they are simply nonspecific responses to cellular injury. When treated with uranyl acetate, type I, II and III structures stain intensely as if they might contain nucleic acids. If these structures do correspond to intermediates in the replication of a virus, one might expect them to contain DNA or RNA and the present study was undertaken to explore this possibility.

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Computation and data driven discovery of topological phononic materials

Nature Communications ◽

10.1038/s41467-021-21293-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jiangxu Li ◽

Jiaxi Liu ◽

Stanley A. Baronett ◽

Mingfeng Liu ◽

Lei Wang ◽

...

Keyword(s):

High Throughput Screening ◽

Electronic System ◽

Nodal Line ◽

Data Driven ◽

Single Type ◽

Type I ◽

Structure Property ◽

Topological Quantum ◽

Data Driven Approach ◽

Spin Electronic

AbstractThe discovery of topological quantum states marks a new chapter in both condensed matter physics and materials sciences. By analogy to spin electronic system, topological concepts have been extended into phonons, boosting the birth of topological phononics (TPs). Here, we present a high-throughput screening and data-driven approach to compute and evaluate TPs among over 10,000 real materials. We have discovered 5014 TP materials and grouped them into two main classes of Weyl and nodal-line (ring) TPs. We have clarified the physical mechanism for the occurrence of single Weyl, high degenerate Weyl, individual nodal-line (ring), nodal-link, nodal-chain, and nodal-net TPs in various materials and their mutual correlations. Among the phononic systems, we have predicted the hourglass nodal net TPs in TeO3, as well as the clean and single type-I Weyl TPs between the acoustic and optical branches in half-Heusler LiCaAs. In addition, we found that different types of TPs can coexist in many materials (such as ScZn). Their potential applications and experimental detections have been discussed. This work substantially increases the amount of TP materials, which enables an in-depth investigation of their structure-property relations and opens new avenues for future device design related to TPs.

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Virulence Factors Found in Nasal Colonization and Infection of Methicillin-Resistant Staphylococcus aureus (MRSA) Isolates and Their Ability to Form a Biofilm

Toxins ◽

10.3390/toxins13010014 ◽

2020 ◽

Vol 13 (1) ◽

pp. 14

Author(s):

Thamiris Santana Machado ◽

Felipe Ramos Pinheiro ◽

Lialyz Soares Pereira Andre ◽

Renata Freire Alves Pereira ◽

Reginaldo Fernandes Correa ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Sccmec Type ◽

Protein A ◽

Invasive Infection ◽

Type I ◽

Methicillin Resistant ◽

Type Iv ◽

Spa Gene ◽

The City

Hospitalizations related to Methicillin-resistant Staphylococcus aureus (MRSA) are frequent, increasing mortality and health costs. In this way, this study aimed to compare the genotypic and phenotypic characteristics of MRSA isolates that colonize and infect patients seen at two hospitals in the city of Niterói—Rio de Janeiro, Brazil. A total of 147 samples collected between March 2013 and December 2015 were phenotyped and genotyped to identify the protein A (SPA) gene, the mec staphylococcal chromosomal cassette (SCCmec), mecA, Panton-Valentine Leucocidin (PVL), icaC, icaR, ACME, and hla virulence genes. The strength of biofilm formation has also been exploited. The prevalence of SCCmec type IV (77.1%) was observed in the colonization group; however, in the invasive infection group, SCCmec type II was prevalent (62.9%). The Multilocus Sequence Typing (MLST), ST5/ST30, and ST5/ST239 analyses were the most frequent clones in colonization, and invasive infection isolates, respectively. Among the isolates selected to assess the ability to form a biofilm, 51.06% were classified as strong biofilm builders. Surprisingly, we observed that isolates other than the Brazilian Epidemic Clone (BEC) have appeared in Brazilian hospitals. The virulence profile has changed among these isolates since the ACME type I and II genes were also identified in this collection.

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Distribution of virulence genes and SCCmec types among methicillin-resistant Staphylococcus aureus of clinical and environmental origin: a study from community of Assam, India

BMC Research Notes ◽

10.1186/s13104-021-05473-3 ◽

2021 ◽

Vol 14 (1) ◽

Cited By ~ 1

Author(s):

Deepshikha Bhowmik ◽

Shiela Chetri ◽

Bhaskar Jyoti Das ◽

Debadatta Dhar Chanda ◽

Amitabha Bhattacharjee

Keyword(s):

Staphylococcus Aureus ◽

Virulence Genes ◽

Methicillin Resistant Staphylococcus Aureus ◽

Virulence Gene ◽

Type I ◽

Methicillin Resistant ◽

Type Iv ◽

Clinical Community ◽

Type V ◽

Sccmec Types

Abstract Objective This study was designed to discover the dissemination of virulence genes in Methicillin-resistant Staphylococcus aureus from clinical, community and environmental settings. Results This study includes 1165 isolates collected from hospital, community and environmental settings. Among them sixty three were confirmed as MRSA with varied SCCmec types viz; type I, type II, type III, type IV, type V, type VI, type VII, type VIII and type XII. The virulence gene such as sea (n = 54), seb (n = 21), eta (n = 27), etb (n = 2), cna (n = 24), ica (n = 2) and tst (n = 30) was also revealed from this study. The study underscores coexistence of resistance cassette and virulence genes among clinical and environment isolates which is first of its kind from this part of the world.

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Brachial supporting structure of Spiriferida (Brachiopoda)

Journal of Paleontology ◽

10.1017/jpa.2020.106 ◽

2020 ◽

pp. 1-15

Author(s):

Zhiwei Yuan ◽

Wen Guo ◽

Dan Lyu ◽

Yuanlin Sun

Keyword(s):

Mantle Cavity ◽

Family Type ◽

Type I ◽

Type Ii ◽

Feeding Apparatus ◽

Single Family ◽

Supporting Structure ◽

Type Iii ◽

Type Iv ◽

Evolutionary Lineages

Abstract The filter-feeding organ of some extinct brachiopods is supported by a skeletal apparatus called the brachidium. Although relatively well studied in Atrypida and Athyridida, the brachidial morphology is usually neglected in Spiriferida. To investigate the variations of brachidial morphology in Spiriferida, 65 species belonging to eight superfamilies were analyzed. Based on the presence/absence of the jugal processes and normal/modified primary lamellae of the spiralia, four types of brachidium are recognized. Type-I (with jugal processes) and Type-II (without jugal processes), both having normal primary lamellae, could give rise to each other by losing/re-evolving the jugal processes. Type-III, without jugal processes, originated from Type-II through evolution of the modified lateral-convex primary lamellae, and it subsequently gave rise to Type-IV by evolving the modified medial-convex primary lamellae. The evolution of brachidia within individual evolutionary lineages must be clarified because two or more types can be present within a single family. Type-III and Type-IV are closely associated with the prolongation of the crura, representing innovative modifications of the feeding apparatus in response to possible shift in the position of the mouth towards the anterior, allowing for more efficient feeding on particles entering the mantle cavity from the anterior gape. Meanwhile, the modified primary lamellae adjusted/regulated the feeding currents. The absence of spires in some taxa with Type-IV brachidium might suggest that they developed a similar lophophore to that in some extant brachiopods, which can extend out of the shell.

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Patterns and Relevance of Langerhans Islet Invasion in Pancreatic Cancer

Cancers ◽

10.3390/cancers13020249 ◽

2021 ◽

Vol 13 (2) ◽

pp. 249

Author(s):

Ruediger Goess ◽

Ayse Ceren Mutgan ◽

Umut Çalışan ◽

Yusuf Ceyhun Erdoğan ◽

Lei Ren ◽

...

Keyword(s):

Diabetes Mellitus ◽

Pancreatic Cancer ◽

Cancer Cells ◽

Tumor Cells ◽

Islet Cells ◽

Human Pancreatic Cancer ◽

Type I ◽

Type Iv ◽

Pancreatic Cancer Cells

Background: Pancreatic cancer‐associated diabetes mellitus (PC‐DM) is present in most patients with pancreatic cancer, but its pathogenesis remains poorly understood. Therefore, we aimed to characterize tumor infiltration in Langerhans islets in pancreatic cancer and determine its clinical relevance. Methods: Langerhans islet invasion was systematically analyzed in 68 patientswith pancreatic ductal adenocarcinoma (PDAC) using histopathological examination and 3D in vitro migration assays were performed to assess chemoattraction of pancreatic cancer cells to isletcells. Results: Langerhans islet invasion was present in all patients. We found four different patterns of islet invasion: (Type I) peri‐insular invasion with tumor cells directly touching the boundary, but not penetrating the islet; (Type II) endo‐insular invasion with tumor cells inside the round islet; (Type III) distorted islet structure with complete loss of the round islet morphology; and (Type IV)adjacent cancer and islet cells with solitary islet cells encountered adjacent to cancer cells. Pancreatic cancer cells did not exhibit any chemoattraction to islet cells in 3D assays in vitro. Further, there was no clinical correlation of islet invasion using the novel Islet Invasion Severity Score (IISS), which includes all invasion patterns with the occurrence of diabetes mellitus. However, Type IV islet invasion was related to worsened overall survival in our cohort. Conclusions: We systematically analyzed, for the first time, islet invasion in human pancreatic cancer. Four different main patterns of islet invasion were identified. Diabetes mellitus was not related to islet invasion. However, moreresearch on this prevailing feature of pancreatic cancer is needed to better understand underlying principles.

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