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1.
Environmental monitoring

Dissection of a pig's heart - learning more

Using spreadsheets in biological education

Children's understanding of eating  相似文献   

2.
Abstract

School and naturalistic education. In order that mankind may correctly fit in the balance of nature young people must be given the right scientific preparation during school years. This is why a better training of science teachers would be so important especially in Italy, where they come straight from University having followed various types of scientific degree courses, mainly theoretical, and with no special preparation for teaching.

The main basic requirement for a science teacher is that he has a solid preparation for laboratory but especially for field work. All other kinds of scientific and pedagogic knowledge is of course important but not as indispensable. It is therefore necessary to give science teachers the naturalistic training that University syllabuses do not provide for. At the same time work done inside the school should be supported from the outside by other organizations such as the Field Studies Council in England, or the « keeper-guides » of Israeli natural parks. In the present Italian school system one immediate step could be taken: teachers of « scientific observations » should not confine themselves to lecturing in classrooms but should spend most of their allotted time with their classes in the field or in the laboratory, in the same way as for instance teachers of « technical applications » do their teaching only in the workshop.  相似文献   

3.
The effects of an oestrogenic compound, similar to those recently linked with falling human sperm counts, were investigated in two common freshwater organisms commonly used in education

Oestrogenic compounds have recently been linked with falling sperm counts in human males and also with cancer of the testes and breast. If these compounds can have such dangerous and dramatic effects in humans, as well as affecting sexual behaviour and physiology of fish, what effects do they have on other members of freshwater food chains? The aim of this investigation was to perform some simple experiments using basic laboratory facilities for student research projects. Daphnia, an important primary consumer and food source for fish, was exposed to increasing amounts of ethynyloestradiol, an oestrogen commonly used in contraceptive tablets. The higher concentrations of the oestrogen (0.1 to 1.0 ppm) were found to significantly reduce the heart rate of the Daphnia after approximately 30 minutes' exposure. It is proposed that such a reduction in the activity of oestrogen exposed Daphnia would make them more prone to predation and therefore increase the accumulation of oestrogens by fish. A further experiment investigated the effects of the oestrogen on photosynthesis in Elodea, a common pond weed. The same concentrations of ethynyloestradiol increased photosynthetic rates which could lead to a proliferation in growth. This again would promote the transfer of these compounds if they accumulate in the tissues for aquatic plants. These experiments on a currently significant topic were performed using readily available organisms and a small capital expenditure, thus making them a pertinent and interesting practical for both Alevel and undergraduate students.  相似文献   

4.
ABSTRACT

This article reflects the collective voices of four early childhood visual arts educators, each of whom is a member of the Early Childhood Art Educators (ECAE) Issues Group of the National Arts Educators Association. The authors frame the article around the ECAE position statement, Art: Essential for Early Learning (2016) Early Childhood Art Educators. (2016). Art: Essential for early learning, position statement on early childhood art education (Rev. ed.). Reston, VA: National Art Education Association. Retrieved from https://www.arteducators.org/advocacy/articles/127-position-statement-on-early-childhood-art-education [Google Scholar], which focuses on the central role of art interactions among young children, educators, environments, and materials. The authors describe eight principles that underlie the statement from philosophical viewpoints, and provide practical examples of the principles in action. Amid a varied policy landscape for visual art in early childhood, the authors assert that children need organized, materials-rich environments that invite discovery, interaction, sensory and kinesthetic exploration, wonder, inquiry, and imagination in relationship with responsive educators who value young children's diverse abilities, interests, questions, ideas, and cultural experiences. The authors explore issues and possibilities resulting when educators work to bring visual arts fully and dynamically into the lives of young children in diverse education and care spaces. In closing, the authors explore the realities of visual arts policies in the early childhood education and art education fields while emphasizing the critical need for supportive pedagogical practices in all early childhood classrooms.  相似文献   

5.
Abbreviations ADME absorption, distribution, metabolism, and excretion

MMGB/SA molecular mechanics generalized born surface area

IFD induced fit docking

RTK receptor tyrosine kinase

NSCLC non-small-cell lung cancer

ATP adenosine triphosphate

OPLS optimized potential for liquid stimulation

RMSD root mean square deviation

HTVS high-throughput virtual screening

SP standard precision

XP extra precision

OPLS-AA optimized potential for liquid stimulation-all atom

MD molecular simulation

MME molecular mechanics energies

SGB surface generalized born

POPC membrane 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine membrane

PDB Protein Data Bank

DDR1 discoidin domain receptor 1

DDR2 discoidin domain receptor 2

DDRs discoidin domain receptors

ECM extracellular matrix

TIP4P transferable intermolecular potential 4 point

NPT constant particle number, pressure and temperature

RMSF root mean square fluctuation

Communicated by Ramaswamy H. Sarma  相似文献   

6.
Abbreviations SAHA suberoylanilide hydroxamic acid

EhHDAC Histone Deacetylase from Entamoeba histolytica

Rg Radius of gyration

RMSD root-mean-square deviation

RMSF root-mean-square fluctuation

MDS molecular dynamics simulation

VMD Visual Molecular Dynamics

NAMD Nanoscale Molecular Dynamics

PBC periodic boundary conditions

PME Particle Mesh Ewald

3D three-dimensional

Cα alpha carbon

FDA Food and Drug Administration

ns nanoseconds

GPU CUDA Graphics Processing Unit Compute Unified Device Architecture

Communicated by Ramaswamy H. Sarma  相似文献   

7.
Autophagy and innate immunity: Insights from invertebrate model organisms   总被引:2,自引:0,他引:2  
Cheng-Ju Kuo 《Autophagy》2018,14(2):233-242
  相似文献   

8.
Abbreviations HA Hemagglutinin

MD Molecular Dynamics

MM-PBSA Molecular Mechanics Poisson–Boltzmann Surface Area

NA Neuraminidase

NAMD Nanoscale Molecular Dynamic Simulation

PMEMD Particle Mesh Ewald Molecular Dynamics

RMSD Root-Mean-Square Deviation

RMSF Root-Mean-Square Fluctuation

SIA sialic acid

VMD Visual Molecular Dynamics

Communicated by Ramaswamy H. Sarma  相似文献   

9.
Abbreviations C catechin

ECG epicatechin gallate

EGCG Epigallocatechin gallate

A Adenine

C cytosine

G Guanine

U uracil

FTIR Fourier transform infrared

Communicated by Ramaswamy H. Sarma  相似文献   

10.
Abstract

Complete functional annotations of proteins are essential to understand the role and mechanisms in pathogenesis. Aminoglycoside nucleotidyltransferases are the subclasses of aminoglycosides modifying enzymes conferring resistance to organisms. Insight into the structural and functional understanding of nucleotidyltransferase family protein provides vital information to combat pathogenesis. Phylogenetic analysis is employed to identify the evolutionary significance and common motif’s present among the homologs of nucleotidyltransferase family protein. Structure, sequence based approaches and molecular docking were implemented to predict the exact function of the protein. Wide distribution of the nucleotidyltransferase family protein in gram-positive and gram-negative organisms are evidenced from phylogenetic analysis. Five common motifs were present in all the homolog’s of nucleotidyltransferase family protein. Sequence-structure based functional annotations predicts that the targeted protein function as ATP-Mg dependent streptomycin adenylyltransferase. Structural comparisons and docking studies correlate well with the identified function. The complete function of nucleotidyltransferase family protein was identified as Streptomycin adenylyltransferase and it could be targeted as a potential therapeutic target to overcome antibiotic resistance.

Communicated by Ramaswamy H. Sarma

Abbreviations AAC aminoglycoside acetyltransferases

AME aminoglycoside modifying enzyme

ANT aminoglycoside nucleotidyltransferases

APH aminoglycoside phosphotransferases

ATP adenosine triphosphate

CASTp computer atlas and surface topography of proteins

DUF domains of unknown function

Glide grid-based ligand docking with energetic

HMM hidden Markov model

MAST motif alignment and search tool

MEGA molecular evolutionary genetics analysis

MEME multiple Em for motif elicitation

MSA multiple sequence alignment

NMP nucleoside monophosphate

NTP nucleoside triphosphate

NT nucleotidyltransferase

OPLS optimized potential for liquid simulation

XP extra precision

  相似文献   

11.
Abbreviations COM center of mass distance

MD molecular dynamics

MM-PBSA Molecular Mechanics Poisson–Boltzmann Surface Area

Nb nanobody

PlGF placenta growth factor

Rg radius of gyration

RMSD root mean-square deviation

SASA solvent-accessible surface area

VEGF vascular endothelial growth factor

  相似文献   

12.
13.
Abstract

Phosphorylation of protein is critical for various cell processes, which preferentially happens in intrinsically disordered proteins (IDPs). How phosphorylation modulates structural ensemble of disordered peptide remains largely unexplored. Here, using replica exchange molecular dynamics (REMD) and Markov state model (MSM), the conformational distribution and kinetics of p53 N-terminal transactivation domain (TAD) 2 as well as its dual-site phosphorylated form (pSer46, pThr55) were simulated. It reveals that the dual phosphorylation does not change overall size and secondary structure element fraction, while a change in the distribution of hydrogen bonds induces slightly more pre-existing bound helical conformations. MSM analysis indicates that the dual phosphorylation accelerates conformation exchange between disordered and order-like states in target-binding region. It suggests that p53 TAD2 after phosphorylation would be more apt to bind to both the human p62 pleckstrin homology (PH) domain and the yeast tfb1?PH domain through different binding mechanism, where experimentally it exhibits an extended and α-helix conformation, respectively, with increased binding strength in both complexes. Our study implies except binding interface, both conformation ensemble and kinetics should be considered for the effects of phosphorylation on IDPs. Abbreviations IDPs intrinsically disordered proteins

REMD replica exchange molecular dynamics

MSM Markov state model

TAD transactivation domain

PH pleckstrin homology

PRR proline-rich region

DBD DNA-binding domain

TET Tetramerization domain

REG regulatory domain

MD molecular dynamics

PME particle-mesh Ewald

TICA time-lagged independent component analysis

CK Chapman–Kolmogorov

GMRQ generalized matrix Rayleigh quotient

SARW self-avoiding random walk

KID kinase-inducible domain

MFPT mean first passage time

DSSP definition of secondary structure of proteins

RMSD root mean square deviation

Rg radius of gyration

Ree end to end distance

Communicated by Ramaswamy H. Sarma  相似文献   

14.
15.
Abstract

N-methyl-D-aspartate receptors (NMDARs), a class of ligand-gated ion channels, are involved in non-selective cation transport across the membrane. These are contained in glutamatergic synapse and produce excitatory effects leading to synaptic plasticity and memory function. GluN1-GluN2B, a subtype of NMDAR(s), has significant role in neurodegeneration, amyloid β (Aβ) induced synaptic dysfunction and loss. Thus, targeting and inhibiting GluN1-GluN2B may be effective in the management of neurodegenerative diseases including Alzheimer’s disease. In the present study, ligand and structure-based approaches were tried to identify the inhibitors. The pharmacophore, developed from co-crystallised ifenprodil, afforded virtual hits, which were further subjected through drug likeliness and PAINS filters to remove interfering compounds. Further comprehensive docking studies, free energy calculations and ADMET studies resulted in two virtual leads. The leads, ZINC257261614 and ZINC95977857 displayed good docking scores of ?12.90 and ?12.20?Kcal/mol and free binding energies of ?60.83 and ?61.83?Kcal/mol, respectively. The compounds were having acceptable predicted ADMET profiles and were subjected to molecular dynamic (MD) studies. The MD simulation produced stable complexes of these ligands with GluN1-GluN2B subunit having protein and ligand RMSD in acceptable limit. Abbreviations AD Alzheimer's disease

ADME Absorption distribution metabolism and excretion

ATD Amino terminal domain

BBB Blood-brain barrier

CNS Central nervous system

CREB cAMP response element binding protein

CTD Carboxy-terminal domain

Glu Glutamate

GMQE Global model quality estimation

HTVS High throughput virtual screening

HIA Human intestinal absorption

LGA Lamarckian genetic algorithm

MD Molecular dynamics

MM-GBSA Molecular mechanics, the Generalised Born model for Solvent Accessibility

NMDAR N-methyl-D-aspartate receptors

PAINS Pan assay interference compounds

RMSD Root-mean square deviation

RMSF Root-mean-square fluctuation

SMARTS SMILES arbitrary target specification

SP standard precision

XP extra precision

Communicated by Ramaswamy H. Sarma  相似文献   

16.
Abstract

By having knowledge about the characteristics of protein interaction interfaces, we will be able to manipulate protein complexes for therapies. Dimer state is considered as the primary alphabet of the most proteins’ quaternary structure. The properties of binding interface between subunits and of noninterface region define the specificity and stability of the intended protein complex. Considering some topological properties and amino acids’ affinity for binding in interfaces of protein dimers, we construct the interface-specific recurrence plots. The data obtained from recurrence quantitative analysis, and accessibility-related metrics help us to classify the protein dimers into four distinct classes. Some mechanical properties of binding interfaces are computed for each predefined class of the dimers. The computed mechanical characteristics of binding patch region are compared with those of nonbinding region of proteins. Our observations indicate that the mechanical properties of protein binding sites have a decisive impact on determining the dimer stability. We introduce a new concept in analyzing protein structure by considering mechanical properties of protein structure. We conclude that the interface region between subunits of stable dimers is usually mechanically softer than the interface of unstable protein dimers. Abbreviations AAB average affinity for binding

ANM anisotropic network model

APC affinity propagation clustering

ASA accessible surface area

CCD inter residues distance

CSC complex stability code

DM distance matrix

ΔGdiss PISA-computed dissociation free energy

GNM Gaussian normal mode analysis

NMA normal mode analysis

PBP protein binding patch

PISA proteins, interfaces, structures and assemblies

rASA relative accessible area in respect to unfolded state of residues

RM recurrence matrix

rP relative protrusion

RP recurrence plot

RQA recurrence quantitative analysis

SEM standard error of mean

Communicated by Ramaswamy H. Sarma  相似文献   

17.
Persistent inflammation within the respiratory tract underlies the pathogenesis of numerous chronic pulmonary diseases including chronic obstructive pulmonary disease, asthma and pulmonary fibrosis. Chronic inflammation in the lung may arise from a combination of genetic susceptibility and environmental influences, including exposure to microbes, particles from the atmosphere, irritants, pollutants, allergens, and toxic molecules. To this end, an immediate, strong, and highly regulated inflammatory defense mechanism is needed for the successful maintenance of homeostasis within the respiratory system. Macroautophagy/autophagy plays an essential role in the inflammatory response of the lung to infection and stress. At baseline, autophagy may be critical for inhibiting spontaneous pulmonary inflammation and fundamental for the response of pulmonary leukocytes to infection; however, when not regulated, persistent or inefficient autophagy may be detrimental to lung epithelial cells, promoting lung injury. This perspective will discuss the role of autophagy in driving and regulating inflammatory responses of the lung in chronic lung diseases with a focus on potential avenues for therapeutic targeting.

Abbreviations AR allergic rhinitis

AM alveolar macrophage

ATG autophagy-related

CF cystic fibrosis

CFTR cystic fibrosis transmembrane conductance regulator

COPD chronic obstructive pulmonary disease

CS cigarette smoke

CSE cigarette smoke extract

DC dendritic cell

IH intermittent hypoxia

IPF idiopathic pulmonary fibrosis

ILD interstitial lung disease

MAP1LC3B microtubule associated protein 1 light chain 3 beta

MTB Mycobacterium tuberculosis

MTOR mechanistic target of rapamycin kinase

NET neutrophil extracellular traps

OSA obstructive sleep apnea

PAH pulmonary arterial hypertension

PH pulmonary hypertension

ROS reactive oxygen species

TGFB1 transforming growth factor beta 1

TNF tumor necrosis factor

  相似文献   

18.
Abbreviations HAS human serum albumin

BSA bovine serum albumin

β-LG beta-lactoglobulin

cis-Pt and trans-Pt Pt(NH3)2Cl2

FTIR Fourier transform infrared

Communicated by Ramaswamy H. Sarma  相似文献   

19.
《MABS-AUSTIN》2013,5(4):370-376
Cells undergoing apoptosis in vivo are rapidly detected and cleared by phagocytes. Swift

recognition and removal of apoptotic cells is important for normal tissue homeostasis

and failure in the underlying clearance mechanisms has pathological consequences

associated with inflammatory and auto-immune diseases. Cell cultures in vitro usually

lack the capacity for removal of non-viable cells because of the absence of phagocytes

and, as such, fail to emulate the healthy in vivo micro-environment from which dead cells

are absent. While a key objective in cell culture is to maintain viability at maximal levels,

cell death is unavoidable and non-viable cells frequently contaminate cultures in

significant numbers. Here we show that the presence of apoptotic cells in monoclonal

antibody-producing hybridoma cultures has markedly detrimental effects on antibody

productivity. Removal of apoptotic hybridoma cells by macrophages at the time of

seeding resulted in 100% improved antibody productivity that was, surprisingly to us,

most pronounced late on in the cultures. Furthermore, we were able to recapitulate this

effect using novel super-paramagnetic Dead-Cert?Nanoparticles to remove non-viable

cells simply and effectively at culture seeding. These results (1) provide direct evidence

that apoptotic cells have a profound influence on their non-phagocytic neighbours in

culture and (2) demonstrate the effectiveness of a simple dead-cell removal strategy for

improving antibody manufacture in vitro.  相似文献   

20.
Abstract

Perfluorinated compounds (PFCs) have serious impacts on human health, which could interfere with the body's signal pathways and affect the normal hormone balance of humans. PFCs were reported to bind to many proteins causing a series of biological effects. It was quite possible that the in vivo action of PFCs was not a single target or a single pathway, suggesting the toxic effect was due to the disturbance of protein or gene network, not limited to the modification of a single target protein or gene. Thus, a PFCs-targets interaction network was constructed and the significant differences in the characteristics of complex networks between the branched PFCs and linear PFCs were observed. A molecular dynamics simulation proved that binding ability of the branched PFCs to the target protein was much weaker than that of the linear PFCs, explaining why the branched PFCs presented significantly difference from the linear PFCs in terms of complex network characteristics. In addition, four target genes were identified as the central node genes of the network. The four target genes were proved to present certain influences on some diseases, which suggested a high correlation between PFCs to these diseases, including obesity, hepatocellular carcinoma and diabetes. The present work was helpful to develop new approaches to identify the key toxic targets of compounds and to explore the toxicity effects on pathways. Abbreviations AR androgen receptor

BPA bisphenol A

ESR1 estrogen receptor 1

ESR2 estrogen receptor 2

GLTP glycolipid transfer protein

HbF the fetal hemoglobin

HBG1 hemoglobin subunit γ-1

hERα human ERα

HSD17B1 hydroxysteroid 17-β dehydrogenase 1

KEGG Kenya encyclopedia of genes and genomes

MD molecular dynamics simulation

PFCs perfluorinated compounds

PFOA perfluorooctanoic acid

PFOS perfluorooctane sulfonate

POPs persistent organic pollutants

RMSD root-mean-square deviation

SHBG sex hormone binding globulin

SPC/E extended simple point charge model

TR thyroid hormone receptor

Communicated by Ramaswamy H. Sarma  相似文献   

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