Gray Bands Research Articles

A genetic explanation for the anhydrite–halite cyclic layers in the Middle Jurassic Louann Salt, U.S. Gulf Coastal Region

ABSTRACT Successions of bipartite layers (couplets) form the bedding fabric of salt stocks of the U.S. Gulf Coastal Region, south-central U.S.A. The cyclic couplets typically have a thickness range of 3–20 cm and a mean of about 10 cm. Each couplet consists of a white band of halite interstratified with a thinner, gray band of halite mixed with anhydrite (generally 3–8 wt % of each couplet). Successions of couplets, which lack siliciclastic beds and significant hiatuses, make up the thick (∼ 1.5 km) Middle Jurassic Louann Salt. Deeply buried (by up to ∼ 18 km), the Louann couplets moved laterally by ductile flow into the base of salt stocks and rose (or appeared to). The Dead Sea is a unique, modern analog of the Louann Salt. The huge lake is a model of how surface evaporation, brine temperature, and double-diffusive salt fingering combined to form the Louann couplets. Halite varves (couplets) presently precipitate from the Dead Sea’s deep (∼ 300 m), marine-like brine. If these modern varves are to be a valid genetic model for the Louann couplets, they too must be annual layers. An explicit similarity of the Louann couplets with two modern and four ancient varve-established evaporitic couplets demonstrates that the Louann anhydrite–halite couplets are truly varves. The Louann varves accumulated at such a rapid rate (∼ 1 m every 10 years) that a deep-water depositional basin must have pre-existed. In the basin, an abrupt destabilized thermocline existed in summer between a surface zone (tens of meters thick) of warm, high-salinity brine and a deep zone (hundreds of meters thick) of cooler, lesser-salinity brine. This disposition resulted in a vertical flux from the thermocline of alternating rising and sinking salt fingers (millimeter wide, centimeter long, and millions per km2). When heat diffused from the warm surface zone into the cooler fingers, their density decreased, they rose, and blended with the ambient brine; and when heat diffused from the warm fingers into the cooler deep zone, their density increased, they sank, and blended with the ambient brine. Salinity also diffused into and from fingers but at a rate ∼ 100 × slower than heat. In summer, the Louann surface zone was NaCl undersaturated because: 1) solar heating caused enhanced NaCl solubility, 2) ascending fingers transferred low-salinity brine into the higher-salinity surface zone, and 3) descending fingers transferred high-salinity brine into the lower salinity deep zone. The Louann surface zone, however, was CaSO4·2H2O supersaturated because of: 1) gypsum’s retrograde solubility and 2) gypsum concentration by evaporation in the surface zone. Gypsum cumulates rained from the surface zone onto the seafloor. As fingers descended from the thermocline into the Louann deep zone, their NaCl salinity state changed from saturated to supersaturated. Cumulate and bottom-growth halite precipitated, and the halite and gypsum accumulated together on the seafloor. With subsequent dehydration of the gypsum, the precipitates formed the thin, gray, anhydrite(halite) summer band of the Louann varves. In the fall, brine above the thermocline began to cool. By mid-winter, energized by wind and convection, the brine column overturned, became significantly cooler, and intensely NaCl-supersaturated. Halite cumulates crystallized throughout and rained onto the seafloor to form the thicker, white, halite winter band of the Louann varves.

Developmental and Housekeeping Genes: Two Types of Genetic Organization in the Drosophila Genome.

We developed a procedure for locating genes on Drosophila melanogaster polytene chromosomes and described three types of chromosome structures (gray bands, black bands, and interbands), which differed markedly in morphological and genetic properties. This was reached through the use of our original methods of molecular and genetic analysis, electron microscopy, and bioinformatics data processing. Analysis of the genome-wide distribution of these properties led us to a bioinformatics model of the Drosophila genome organization, in which the genome was divided into two groups of genes. One was constituted by 65, in which the genome was divided into two groups, 62 genes that are expressed in most cell types during life cycle and perform basic cellular functions (the so-called "housekeeping genes"). The other one was made up of 3162 genes that are expressed only at particular stages of development ("developmental genes"). These two groups of genes are so different that we may state that the genome has two types of genetic organization. Different are the timings of their expression, chromatin packaging levels, the composition of activating and deactivating proteins, the sizes of these genes, the lengths of their introns, the organization of the promoter regions of the genes, the locations of origin recognition complexes (ORCs), and DNA replication timings.

DIFFERENT PROTEIN GROUPS INVOLVED IN TRANSCRIPTION REGULATION IN GENES OF DEVELOPMENT AND HOUSEKEEPING IN <i>DROSOPHILA</i>

Antibodies to histone modifications and an insulator protein involved in the processes of transcription initiation and elongation are mapped in Drosophila polytene chromosomes. The CHRIZ protein (chromatin insulator) and H3K36me3 histone modification (RNA elongation) are detected only in the localization of housekeeping genes (interbands and gray bands of polytene chromosomes) and never in the regions of development genes (black bands and large puffs arising from them). Antibodies to H3S10P histone modification, which is associated with the initial elongation of the RNA strand during transcription, are found exclusively in small puffs, but not in housekeeping gene localization sites or large ecdysone-induced puffs, where housekeeping genes are localized. Antibodies to H4R3me2 histone modification (a co-repressor of the ecdysone receptor) are detected only in large α-induced puffs.

Use of Underwater-Image Color to Determine Suspended-Sediment Concentrations Transported to Coastal Regions

The amount of suspended sediment transported from rivers to the ocean fluctuates over time, with a substantial increase occurring during storm events. This surge in sediment poses numerous challenges to coastal areas, highlighting the importance of accurately assessing the sediment load to address these issues. In this study, we developed and experimentally verified a novel method for suspended-sediment-discharge quantification in estuaries and coasts using underwater imaging. Specifically, red clay samples with different particle sizes were introduced into separate tanks containing clean water. After adequate mixing, the concentration, particle size, turbidity, and water quality were measured and analyzed using LISST-200x and EXO2 Multiparameter Sonde sensors. To maintain constant lighting conditions, a camera box was created for filming. Based on the experimental results, a turbidity–concentration relationship formula was derived. The proposed regression equation revealed that the relationship between the turbidity and estimated suspended-sediment concentration was significantly affected by the particle size, and the prediction results were underestimated under high-concentration conditions. Using blue, green, and gray band values, a multiple regression model for estimating suspended-sediment concentrations was developed; its predictions were better than those obtained from the turbidity–concentration relationship. Following efficiency improvements through additional approaches considering underwater-image filming conditions and characteristics of actual streams, estuaries, and coasts, this method could be developed into an easily usable technique for sediment-discharge estimation, helping address sediment-related issues in estuaries and coastal regions.

Performance modeling of quartz tube for gravity-driven solid particle solar receiver

The interest in high-temperature solar receivers is increasing due to more and more applications in industrial fields. The solid particle is a promising heat transfer fluid for high-temperature receivers owing to the advantages of direct absorption, low cost, and high allowable temperature (∼1300 °C). The re-radiation losses of solid particles inevitably increase with the higher operating temperature. The quartz tube with a spectral selective transmissivity may be used for reducing re-radiation losses. This paper proposed a mathematical model to describe the heat transfer behaviors of the gravity-driven solid particle solar receiver with a quartz tube covered. The wavelength-dependent radiative properties of the quartz tube and particles were approximated by a gray band method. On-sun tests based on a linear-focused solar furnace were conducted, and test results verified the proposed model. Analysis results show that a reduction in β from 3676m−1 to 1000m−1 can boost the volume absorption effect and increase the solar-to-thermal efficiency from 0.54 to 0.64. A double-layered quartz tube design provides the best thermal performance by increasing the greenhouse effect of the quartz tube from −0.02∼0.08 to 0.41. The analysis results could be used for the optimal design and operation of the gravity-driven solid particle solar receiver.

Hyporthodus griseofasciatus (Perciformes: Epinephelidae), a new species of deep-water grouper from the west coast of Australia.

A new species of deep-water epinephelid fish is described from the west coast of Australia based on 14 specimens, 99-595 mm standard length. Hyporthodus griseofasciatus sp. nov. is endemic to Western Australia from Barrow Island to Two Peoples Bay in depths of 76-470 m. It has a series of eight grey bands alternating with eight brown bands along the body and the soft dorsal, soft anal and caudal fin margins are pale cream to white. It is distinguished from its nearest congener, H. ergastularius, by the presence of a star-like pattern of radiating lines on the head versus an overall brownish colour in the latter as well as significant differences in the quantitative analyses of 25 morphological characters. The two species have allopatric distributions on either side of the Australian continent. H. griseofasciatus is distinguished from H. octofasciatus by several grey bands being distinctly narrower than other grey bands (vs. all grey bands subequal in the latter) and the presence of broad white margins on the dorsal, caudal and anal fins (vs. narrow or absent in the latter). Some scale counts appear to also differ. Analyses of mitochondrial cytochrome oxidase subunit 1 sequences revealed reciprocally monophyletic clades with fixed differences and genetic distances typical of recently diverged species of fishes.

Novel DCX pathogenic variant in a girl with subcortical band heterotopia

Abstract Subcortical band heterotopia (SBH), is a brain malformation defined by symmetrical and bilateral heterotopic gray matter bands localized deep within the white matter, between the cortex and lateral ventricles. SBH is the result of abnormal neuronal migration, with improper positioning of the cortical neurons. DCX gene (doublecortin), a microtubule-associated protein with essential roles in neuronal migration and differentiation during brain development, is one of the main contributors to the X-linked Lissencephaly spectrum pathogenesis (OMIM #300067). DCX variants are responsible for SBH in females and isolated lissencephaly in males. Herein, we present a 7-year-old girl with a de novo frameshift variant in DCX gene, unreported by date. The patient has focal complex seizures with onset at 23 months of age, fully controlled with medication, mild tremor and coordination impairment of fine movements and some learning difficulties, otherwise with normal development. The brain magnetic resonance imaging revealed the presence of thick SBH. Direct sequencing of DCX gene revealed a pathogenic heterozygous cytosine duplication in exon 3; this frameshift variant leads to a premature stop codon in position 164 (p.Gln160Profs*5). The variant type and its predicted consequence at protein level correlates with the severity of radiological findings. The clinical presentation of our patient is, however, milder than expected. Our research expands the mutational spectrum of DCX gene in SBH females and provides a detailed clinical and imagistic description of the patient. This paper highlights the utility of single gene sequencing as a first-tier diagnostic test of patients with gene-specific phenotypic features.

The quantitative characterization of stylolites in the limestone reservoirs of the Lower Triassic Feixianguan Formation, northeastern Sichuan Basin: Insights to the influence of pressure solution on the quality of carbonate reservoirs

Pressure solution, a common and important diagenetic process in carbonates, involves physical reduction of the volume in rocks and chemical dissolution-precipitation process in pores, and thus leads to the significant heterogeneity of reservoirs. Stylolite is a typical product of pressure solution. The amplitude and residual seam thickness of stylolite can effectively characterize the intensity of pressure solution. Quantitative characterization of the density, morphology, and distribution of stylolites in the Feixianguan Formation limestones in the northeastern Sichuan Basin were performed to evaluate the intensity of pressure solution. Revealing the impact of pressure solution on the evolution of porosity and permeability is essential when looking for high-quality reservoirs by integrating quantitative statistics from cores and thin sections with geochemical data. The following four types of stylolites were observed in the Feixianguan limestones according to pure geometry, known as wave-like, rectangular, sharp-peak, and seismogram types. From matrix supported limestone to grain supported limestone, the type of stylolites gradually change from wave-like to rectangular, sharp-peak and seismogram types, accompanied by increased surface roughness and amplitudes, and significantly decreased residual seam thicknesses. The stylolite density tends to decrease from the lower to upper part of the sedimentary cycle. The dissolved calcium carbonates released via pressure solution precipitated as cement in adjacent pore spaces, forming a relatively less porous light gray band on each side of the stylolite. We implement two quantitative methods show that the intensity of pressure solution in grainstone (90.42 mm/m) is significantly smaller than that in mudstone (235.78 mm/m) suggesting that the grainstones are more resistant to chemical compaction. Moreover, pressure solution caused a decrease in the porosity of limestone by approximately 11.31%. The porosity of grainstones varies widely and decreases drastically as clay content increases, suggesting that the clean particles formed in high-energy environments are favorable for the formation of dominant reservoirs. A large number of pores, calcite cements, and bitumen within stylolites indicates that stylolites could act as fluid pathways, contributing about an order of magnitude to the reservoir permeability. Concludingly, we highlight quantitatively differences in pressure solution intensity on a millimeter scale.

Dermoscopic Evaluation of Longitudinal Melanonychia in Children: A Prospective Study.

Background:Longitudinal melanonychia (LM) is a worrisome sign in both children and adults. Nail apparatus melanoma (NAM) can be related to LM, but it is very rare in children. Dermoscopic signs of benign lesions in children can be similar to melanoma; therefore, it is important to review dermoscopy of LM in children to make the best decision in performing biopsy.Aims:Biopsy taking is very challenging in LM in children. Most lesions are benign in children. The aim of this study was to review dermoscopic signs of LM in children and compare them with adults.Materials and Methods:In this prospective study a total of 108 LM (35 children and 73 adults) were undergone dermoscopy of LM. Dermoscopic features were compared in children and adults; both for benign lesions proven by biopsy or follow up and melanomas diagnosed histopathologically.Results:Black background, black band color, band color diversity and pseudo-Hutchinson's sign were more frequent in children in comparison with benign adult melanonychia. Some children's dermoscopic features of LM such as broad band width, Band color diversity, Hutchinson's sign, gray band color, asymmetry of pattern, and regression were similar to melanoma, but we did not find any melanoma by biopsy and/or follow up among children. We also detected the newly described "zigzag" pattern in four children.Conclusion:Dermatologists should consider all dermoscopic features of a lesion, dermoscopic sign changes in follow-up, medical, and familial history of the patient in deciding to perform biopsy of LM in children.

Comparative effect of osmium tetroxide and ruthenium tetroxide on Lacazia loboi ultrastructure.

Lobomycosis is a skin infection produced by the fungus Lacazia loboi, which mainly affects some indigenous and afro-descendant populations in Tropical America. We previously reported the comparative effect of osmium tetroxide (OsO4 ) and ruthenium tetroxide (RuO4 ) in the electron microscopy (EM) of other related microorganisms. The objective of this study is to compare the effect of postfixation with OsO4 and RuO4 in the ultrastructure of L. loboi yeasts. Skin biopsies on patients diagnosed with lobomycosis were fixed in glutaraldehyde at 3% and postfixed in the following solutions: (a) 1% OsO4 , (b) 0.2% RuO4 , and (c) OsO4 at 1% followed by RuO4 at 0.2%. They were then processed using the conventional method for EM. Unlike OsO4, the treatment with RuO4 revealed different shades of gray and electron dense bands in the cell wall and other cell components of L. loboi. The most notable finding was the presence of radial filamentous structures around the yeast, which made the image look like the sun. Postfixation with RuO4 revealed ultrastructural details that had not been previously reported for L loboi. The combined use of OsO4 and RuO4 in EM of microorganisms with cell walls can be useful to evaluate the effect of microbicide substances.

A new species of Toxicocalamus (Squamata: Elapidae) from Papua New Guinea.

I describe a new species of the fossorial elapid snake genus Toxicocalamus from Mt. Simpson, Milne Bay Province, in southeastern New Guinea. The new species is similar to the poorly diagnosed T. loriae but differs from that species (and all other Toxicocalamus with the preocular distinct from the prefrontal) in having the preocular not in contact with the nasal and in having a pale-gray or yellow venter with gray bands across each ventral scale. The new species came from elevations of 1300-1490 m a.s.l. on the north slope of Mt. Simpson, and it seems likely to be confined to the mid-elevations of that mountain, judging from its morphological differences with specimens obtained from similar elevations on nearby Mt. Dayman. If true, this would make it the sixth species of herpetofauna apparently endemic to Mt. Simpson. This snake was common and found in both village gardens and adjacent primary rainforest, and I estimate its area of extent to be approximately 50,000 ha, so its IUCN conservation status would appear to be Least Concern.

Genes Containing Long Introns Occupy Series of Bands and Interbands In Drosophila melanogaster polytene Chromosomes.

The Drosophila melanogaster polytene chromosomes are the best model for studying the genome organization during interphase. Despite of the long-term studies available on genetic organization of polytene chromosome bands and interbands, little is known regarding long gene location on chromosomes. To analyze it, we used bioinformatic approaches and characterized genome-wide distribution of introns in gene bodies and in different chromatin states, and using fluorescent in situ hybridization we juxtaposed them with the chromosome structures. Short introns up to 2 kb in length are located in the bodies of housekeeping genes (grey bands or lazurite chromatin). In the group of 70 longest genes in the Drosophila genome, 95% of total gene length accrues to introns. The mapping of the 15 long genes showed that they could occupy extended sections of polytene chromosomes containing band and interband series, with promoters located in the interband fragments (aquamarine chromatin). Introns (malachite and ruby chromatin) in polytene chromosomes form independent bands, which can contain either both introns and exons or intron material only. Thus, a novel type of the gene arrangement in polytene chromosomes was discovered; peculiarities of such genetic organization are discussed.

Color Difference Optimization Method for Multi-source Remote Sensing Image Processing

This paper proposes an approach to solve the problem of color inconsistency after the fusion and splicing of multi-spectral images of multi-source domestic satellites, by using regularly division the high-resolution remote sensing images, block by block computing the multiple linear regression and percent clip stretch. First of all, the remote sensing image is divided into blocks and multiple linear regression is carried out separately in each block. Secondly, on the basis of the image to be corrected after regression, percentage truncation and stretching are carried out on the over-concentrated gray band, so that the gray histogram distribution of the gray band is similar to that of the reference image. This scheme ensures that all pixels participate in the calculation, which not only improves the accuracy of the model, but also avoids the problems of long processing time and memory overflow caused by the large amount of high-resolution remote sensing image data. At the same time, each scene image selects an appropriate truncation percentage according to the evaluation index to solve the problem of excessive color difference caused by too concentrated image band gray. The experimental results show that the scheme in this paper can effectively solve the problems of too large color difference and too concentrated gray scale in image band. Compared with traditional methods, it has better performance in model accuracy, color retention and time efficiency.

Faint gray bands in Drosophila melanogaster polytene chromosomes are formed by coding sequences of housekeeping genes.

In Drosophila melanogaster, the chromatin of interphase polytene chromosomes appears as alternating decondensed interbands and dense black or thin gray bands. Recently, we uncovered four principle chromatin states (4НММ model) in the fruit fly, and these were matched to the structures observed in polytene chromosomes. Ruby/malachite chromatin states form black bands containing developmental genes, whereas aquamarine chromatin corresponds to interbands enriched with 5' regions of ubiquitously expressed genes. Lazurite chromatin supposedly forms faint gray bands and encompasses the bodies of housekeeping genes. In this report, we test this idea using the X chromosome as the model and MSL1 as a protein marker of the lazurite chromatin. Our bioinformatic analysis indicates that in the X chromosome, it is only the lazurite chromatin that is simultaneously enriched for the proteins and histone marks associated with exons, transcription elongation, and dosage compensation. As a result of FISH and EM mapping of a dosage compensation complex subunit, MSL1, we for the first time provide direct evidence that lazurite chromatin forms faint gray bands. Our analysis proves that overall most of housekeeping genes typically span from the interbands (5' region of the gene) to the gray band (gene body). More rarely, active lazurite chromatin and inactive malachite/ruby chromatin may be found within a common band, where both the housekeeping and the developmental genes reside together.

Non-Native Neotropical Nesting Whitefly, <i>Paraleyrodes minei</i> Iaccarino on Coconut Palms in India and its Co-Existence with Bondar’s Nesting Whitefly, <i>Paraleyrodes bondari</i> Peracchi

Field occurrence of the exotic neotropical nesting whitefly, Paraleyrodes minei Iaccarino in association with Bondar’s nesting whitefly, Paraleyrodes bondari Peracchi on coconut leaflets is reported from Kerala, India. These coconut palms were previously infested by the rugose spiralling whitefly, Aleurodicus rugioperculatus Martin, which was reported from Kerala and Tamil Nadu during 2016. P. minei closely resembles P. bondari , but is devoid of the oblique grey bands on the wings and it constructs loosely woven, woolly wax nests. Female P. minei are white, but males are smoky grey. Cockhead-like male aedeagus with two thin appendixes projected downwards is the unique feature for species-level identification of P. minei . Detection of three non-native whiteflies of neotropical origin infesting coconut palms in India within a span of two years suggests their simultaneous introduction. Invasive potential of P. minei due to its polyphagous nature and short lifecycle calls upon strict policy frameworks in exchange of planting materials. Domestic quarantine should be strictly enforced in the country to avoid spread of this pest to other coconut-growing regions.

Thin Layer Chromatographic Identification of the Whole Plant of Sangketan (Achyranthes Aspera)

Medicine plant is a great source of information for variety of phytochemicals which can be developed as drug with the right selectivity. One of the potential plants developed as anticancer drugs is Sangketan (Achyranthes aspera). In the in vivo study showed that Achyranthes aspera causes apoptosis and healing to breast cancer cells induced by benzopyrene. This study deals with early phytochemicals screening using thin layer chromatography of Achyranthes aspera. Sangketan powder is extracted by reflux method on water bath with temperature of 50°C using ethanol, methanol and petroleum ether solvent. The extract from filtering is concentrated on water bath using porcelain dish. After obtaining the extract concentrated, it is dissolved with a suitable solvent, then elluted on Silica Gel 60 F254 stationary phase with various mobile phase comparison (chloroform : methanol). In qualitative analysis, phytochemical compounds such as steroids, triterpenoid, sugar, alkaloids, phenolic compounds, flavonoids were extracted in Sangketan using standard methods. The screening uses thin layer chromatography with chloroform : methanol of (8: 2 v / v), showing some gray bands after spraying vanillin - sulphate acid reagent. This result reveals that Achyranthes aspera is an important source of various active therapeutic and pharmacological properties.

구조-텍스처 분할을 이용한 위성영상 융합 프레임워크

This paper proposes a novel framework for image fusion of satellite imagery to enhance spatial resolution of the image via structure-texture decomposition. The resolution of the satellite imagery depends on the sensors, for example, panchromatic images have high spatial resolution but only a single gray band whereas multi-spectral images have low spatial resolution but multiple bands. To enhance the spatial resolution of low-resolution images, such as multi-spectral or infrared images, the proposed framework combines the structures from the low-resolution image and the textures from the high-resolution image. To improve the spatial quality of structural edges, the structure image from the low-resolution image is guided filtered with the structure image from the high-resolution image as the guidance image. The combination step is performed by pixel-wise addition of the filtered structure image and the texture image. Quantitative and qualitative evaluation demonstrate the proposed method preserves spectral and spatial fidelity of input images.

Interhypothalamic adhesions in endoscopic third ventriculostomy.

An interhypothalamic adhesion (IHA) is a gray mater-like band of tissue traversing across the third ventricle anterior to the mammillary bodies and is similar but distinct from an interthalamic adhesion. These rare anatomic anomalies can be detected with magnetic resonance imaging or, incidentally, during endoscopic ventricular surgery. All cases of interhypothalamic adhesions visualized during endoscopic third ventriculotomy (ETV), outside of the myelomeningocele setting, were identified from two institutions. Retrospective chart and imaging reviews were conducted and compared to intraoperative videos and photos for all cases. IHA variables collected included the following size, location, multiplicity, and associated anatomic anomalies. Four cases of interhypothalamic adhesions were identified during ETV-all of which, either partially or completely, obscured access to the third ventricular floor. The IHAs in our cohort were duplicated in two patients, large (> 3mm and severely obstructing access to the third ventricular floor) in three patients, and adherent to the floor of the third ventricle in three patients. All four patients had primary absence of the septum pellucidum. Previous reports found associations of IHAs with other congenital, particularly midline, abnormalities. The IHAs in our cohort affected the surgery in three of four cases including misdirecting the ventriculostomy and requiring retraction or division of the IHA. In no case was postoperative pituitary or hypothalamic dysfunction observed. Although interhypothalamic adhesions are rare, these anomalies must be recognized as they may hinder access to the third ventricular floor. IHAs may be large, multiple, or adherent to adjacent ventricular structures, they can misdirect or occlude the ventriculostomy or impart risk of bleeding and hypothalamic injury. Techniques for management of IHA include aborting the attempt, re-siting the ventriculostomy, or retracting or dividing the IHA, which enabled technically successful ETV in three of four patients in this series.

Manipulating Initial Peak vGRF During Walking Affects Loading Throughout Stance in Individuals with ACL Reconstruction

Gait alterations may be associated with osteoarthritis development following anterior cruciate ligament reconstruction (ACLR). Novel gait retraining paradigms are being developed to optimize peak vertical limb loading in the first half of stance; yet the effect of changing this single discrete variable on loading characteristics across the entire stance phase remain unknown. PURPOSE: Determine the effect of increasing and decreasing the first peak of the vertical ground reaction force (vGRF) by 5% during walking using real-time biofeedback (RTBF) of vGRF throughout stance. METHODS: 30 ACLR participants (21 females, 20.4±2.9 yrs, 172.7±10.8 cm, 73.2±16.1 kg, 47.8±4.2 months post-ACLR) completed one 20-minute control condition and two experimental conditions (high- and low-loading). For high- and low-load conditions, participants walked for 20 minutes on a force-measuring treadmill with RTBF displayed on a screen cuing a 5% increase (high) or decrease (low) in the first peak of the vGRF relative to vGRF collected in the control condition. VGRFs were collected at 1000 Hz throughout the 19th minute. Two functional analyses of variance were conducted to evaluate VGRF magnitude throughout stance. RESULTS: Figures 1A and 1C depict mean vGRF, normalized to body weight (BW), throughout the stance phase. Figures 1B and 1D depict pairwise comparison functions (solid black lines) and associated 95% confidence intervals (gray bands), indicating mean differences between the two conditions. Significant between-condition differences existed in the high-loading condition between 42 and 74% of stance, and in the low-loading condition (between 38 and 70%, and 76 and 97% of stance. CONCLUSION: RTBF, used to cue changes in the first vGRF peak, results in loading alterations throughout stance. Specifically, high loading results in lesser vGRF at midstance but a similar propulsive peak. Conversely, low loading increases vGRF during midstance and decreases vGRF during toe-off.

Molecular and genetic organization of bands and interbands in the dot chromosome of Drosophila melanogaster

The fourth chromosome smallest in the genome of Drosophila melanogaster differs from other chromosomes in many ways. It has high repeat density in conditions of a large number of active genes. Gray bands represent a significant part of this polytene chromosome. Specific proteins including HP1a, POF, and dSETDB1 establish the epigenetic state of this unique chromatin domain. In order to compare maps of localization of genes, bands, and chromatin types of the fourth chromosome, we performed FISH analysis of 38 probes chosen according to the model of four chromatin types. It allowed clarifying the dot chromosome cytological map consisting of 16 loose gray bands, 11 dense black bands, and 26 interbands. We described the relation between chromatin states and bands. Open aquamarine chromatin mostly corresponds to interbands and it contains 5′UTRs of housekeeping genes. Their coding parts are embedded in gray bands substantially composed of lazurite chromatin of intermediate compaction. Polygenic black bands contain most of dense ruby chromatin, and also some malachite and lazurite. Having an accurate map of the fourth chromosome bands and its correspondence to physical map, we found that DNase I hypersensitivity sites, ORC2 protein, and P–elements are mainly located in open aquamarine chromatin, while element 1360, characteristic of the fourth chromosome, occupies band chromatin types. POF and HP1a proteins providing special organization of this chromosome are mostly located in aquamarine and lazurite chromatin. In general, band organization of the fourth chromosome shares the features of the whole Drosophila genome.