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2.
J Phys Chem Lett ; 14(32): 7208-7214, 2023 Aug 17.
Article in English | MEDLINE | ID: mdl-37551605

ABSTRACT

WO3 is a 5d compound that undergoes several structural transitions in its bulk form. Its versatility is well-documented, with a wide range of applications, such as flexopiezoelectricity, electrochromism, gating-induced phase transitions, and its ability to improve the performance of Li-based batteries. The synthesis of WO3 thin films holds promise in stabilizing electronic phases for practical applications. However, despite its potential, the electronic structure of this material remains experimentally unexplored. Furthermore, its thermal instability limits its use in certain technological devices. Here, we employ tensile strain to stabilize WO3 thin films, which we call the pseudotetragonal phase, and investigate its electronic structure using a combination of photoelectron spectroscopy and density functional theory calculations. This study reveals the Fermiology of the system, notably identifying significant energy splittings between different orbital manifolds arising from atomic distortions. These splittings, along with the system's thermal stability, offer a potential avenue for controlling inter- and intraband scattering for electronic applications.

3.
Arch Razi Inst ; 78(2): 721-727, 2023 04.
Article in English | MEDLINE | ID: mdl-37396739

ABSTRACT

This study aimed to investigate the efficacy of emptied ovarian follicles of sheep as a container for cryopreservation of human spermatozoa to preserve the presence of low concentrations of spermatozoa at the post-thawing stage. This research was performed on 30 semen samples from oligozoospermic patients and 10 samples from normozoospermic males. They were diagnosed according to the standard criteria of the World Health Organization 2010. Semen samples were classified into four groups of G1-G4 according to sperm concentration: 3-5 million/mL, 6-10 million/mL, 11-15 million/mL, and 16-20 million/mL, respectively. Each sample was divided into two equal parts. One part was cryopreserved without cryoprotectant, while the other was diluted 1:1 with 10% glycerol-based cryosolution. The ovarian follicles of sheep were obtained from a local slaughterhouse and prepared by slicing the ovaries and evacuating the follicular fluid and oocyte. The emptied follicles were injected with the prepared semen samples. After cryopreservation and thawing, the semen mixture aspired outside the follicles, and sperm parameters were measured, namely concentration, progressive motility, total motility, and normal morphology. Sperm concentration and progressive and total sperm motility were significantly (P<0.01) decreased in all groups at the post-thawing stage, compared to the pre-freezing stage. The sperm concentration was significantly higher (P<0.01) in samples cryopreserved without cryoprotectant, compared to that in those cryopreserved with glycerol. However, progressive and total motility were significantly (P<0.01) higher in samples cryopreserved with glycerol, compared to that in the samples cryopreserved without cryoprotectant in all groups. Moreover, no significant difference was found between the pre-freezing and post-thawing stages in terms of normal morphology. Emptied ovarian follicles are an appropriate carrier for cryopreservation of human sperms, especially for patients with oligozoospermia. The best sperm survival rate in this technique was observed when using glycerol-based cryosolution.


Subject(s)
Semen Preservation , Semen , Humans , Male , Animals , Sheep , Female , Glycerol/pharmacology , Sperm Motility , Semen Preservation/veterinary , Semen Preservation/methods , Cryopreservation/veterinary , Cryopreservation/methods , Spermatozoa , Ovarian Follicle
4.
Soft comput ; 27(14): 9519-9531, 2023.
Article in English | MEDLINE | ID: mdl-37287570

ABSTRACT

Tuberculosis (TB) is a deadly contagious disease that affects vital organs of the body, especially the lungs. Although the disease is preventable, there are still concerns about its continued spread. Without effective prevention or appropriate treatment, TB infection can be fatal to humans. This paper presents a fractional-order TB disease (FTBD) model to analyze TB dynamics and a new optimization method to solve it. The method is based on the basis functions of generalized Laguerre polynomials (GLPs) and some new operational matrices of derivatives in the Caputo sense. Finding the optimal solution to the FTBD model is reduced to solving a system of nonlinear algebraic equations with the aid of GLPs using the Lagrange multipliers method. A numerical simulation is also carried out to determine the impact of the presented method on the susceptible, exposed, infected without treatment, infected with treatment, and recovered cases in the population.

5.
Article in Russian | MEDLINE | ID: mdl-38289306

ABSTRACT

INTRODUCTION: In order to optimize rehabilitation measures for post-traumatic stress disorder (PTSD) it is advisable to use natural therapeutic factors in the medical rehabilitation programmes of this category of patients, which is due to the pronounced psycho-corrective effects of climatic landscape therapy and nitrogen-thermal waters. AIM: To study psycho-corrective effects of a new rehabilitation technique for the patients suffering from PTSD using natural therapeutic factors of Nalchik resort. MATERIAL AND METHODS: Thera has been carried out a randomized controlled trial that included 74 patients with PTSD. Two groups were formed by simple randomization: in the control group (CG/n=38) the patients had standardized pharmacotherapy, physical training and individual psychocorrection in accordance with federal clinical recommendations; in the main group (MG/n=36) terrencourt in the natural park of Nalchik resort and nitrogen-thermal baths were additionally prescribed. The effectiveness of rehabilitation measures was monitored using a questionnaire to assess the therapeutic dynamics of PTSD, the Beck Hopelessness scale, as well as the Neurotech Kolibri wireless BFB complex (Russia). RESULTS: A comparative analysis of monitoring of psycho-emotional status indicators proved the feasibility of the developed medical rehabilitation programme for PTSD patients. A significant improvement in psychoemotional status was observed according to the questionnaire for assessing the therapeutic dynamics of PTSD (on average by 2 times, p<0.01), according to the Beck hopelessness scale, according to which the clinically assessed suicidal risk and hopelessness level were reduced by 1.7 (p<0.01) times with the patients in the MG. According to the analysis of brain biopotentials during the primary training, the patients had insufficient control over the course of mental activity (63%), and at the end of the course the indicator improved to 97% (p<0.01). In the CG positive dynamics on both scales of psychological testing and analysis of brain biopotentials was significantly lower (by 12-15%, p<0.05-p<0.01). CONCLUSION: After including in the standardized rehabilitation programme controlled walking in the mid-mountain Natural Park and nitrogen-thermal baths of Nalchik resort, there was a significant improvement in the psycho-emotional status of the patients suffering from PTSD, which indicates their psychocorrective effects and provides great opportunities to improve the effectiveness of medical rehabilitation.


Subject(s)
Stress Disorders, Post-Traumatic , Humans , Stress Disorders, Post-Traumatic/therapy , Anxiety , Emotions , Brain , Nitrogen
6.
Sci Rep ; 11(1): 15622, 2021 08 02.
Article in English | MEDLINE | ID: mdl-34341390

ABSTRACT

In this article, a fractional order breast cancer competition model (F-BCCM) under the Caputo fractional derivative is analyzed. A new set of basis functions, namely the generalized shifted Legendre polynomials, is proposed to deal with the solutions of F-BCCM. The F-BCCM describes the dynamics involving a variety of cancer factors, such as the stem, tumor and healthy cells, as well as the effects of excess estrogen and the body's natural immune response on the cell populations. After combining the operational matrices with the Lagrange multipliers technique we obtain an optimization method for solving the F-BCCM whose convergence is investigated. Several examples show that a few number of basis functions lead to the satisfactory results. In fact, numerical experiments not only confirm the accuracy but also the practicability and computational efficiency of the devised technique.


Subject(s)
Breast Neoplasms , Algorithms , Female , Humans
7.
Soft Matter ; 13(37): 6297-6303, 2017 Sep 27.
Article in English | MEDLINE | ID: mdl-28920620

ABSTRACT

The current modification of polydimethylsiloxane (PDMS) substrates via oxygen plasma treatment causes surface cracks. Here, we demonstrate a method to prevent crack formation by chemical treatment. Chemical modification renders the surface hydrophilic for several days and is effective in preserving the elasticity of the PDMS surface at the nanoscale level.

8.
Am J Bot ; 104(1): 161-181, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28031167

ABSTRACT

PREMISE OF THE STUDY: Molecular genetic evidence can help delineate taxa in species complexes that lack diagnostic morphological characters. Pinus ponderosa (Pinaceae; subsection Ponderosae) is recognized as a problematic taxon: plastid phylogenies of exemplars were paraphyletic, and mitochondrial phylogeography suggested at least four subdivisions of P. ponderosa. These patterns have not been examined in the context of other Ponderosae species. We hypothesized that putative intraspecific subdivisions might each represent a separate taxon. METHODS: We genotyped six highly variable plastid simple sequence repeats in 1903 individuals from 88 populations of P. ponderosa and related Ponderosae (P. arizonica, P. engelmannii, and P. jeffreyi). We used multilocus haplotype networks and discriminant analysis of principal components to test clustering of individuals into genetically and geographically meaningful taxonomic units. KEY RESULTS: There are at least four distinct plastid clusters within P. ponderosa that roughly correspond to the geographic distribution of mitochondrial haplotypes. Some geographic regions have intermixed plastid lineages, and some mitochondrial and plastid boundaries do not coincide. Based on relative distances to other species of Ponderosae, these clusters diagnose four distinct taxa. CONCLUSIONS: Newly revealed geographic boundaries of four distinct taxa (P. benthamiana, P. brachyptera, P. scopulorum, and a narrowed concept of P. ponderosa) do not correspond completely with taxonomies. Further research is needed to understand their morphological and nuclear genetic makeup, but we suggest that resurrecting originally published species names would more appropriately reflect the taxonomy of this checkered classification than their current treatment as varieties of P. ponderosa.


Subject(s)
Genetic Variation , Haplotypes , Pinus ponderosa/genetics , Pinus/genetics , Alleles , Discriminant Analysis , Gene Frequency , Genotype , Geography , Microsatellite Repeats/genetics , Phylogeny , Pinus/classification , Plastids/genetics , Principal Component Analysis , Sequence Analysis, DNA , Species Specificity , United States
9.
Sci Rep ; 6: 35951, 2016 10 24.
Article in English | MEDLINE | ID: mdl-27775028

ABSTRACT

Climate shifts at decadal scales can have environmental consequences, and therefore, identifying areas that act as environmental refugia is valuable in understanding future climate variability. Here we illustrate how, given appropriate geohydrology, a rift basin and its catchment can buffer vegetation response to climate signals on decadal time-scales, therefore exerting strong local environmental control. We use time-series data derived from Normalised Difference Vegetation Index (NDVI) residuals that record vegetation vigour, extracted from a decadal span of MODIS images, to demonstrate hydrogeological buffering. While this has been described previously it has never been demonstrated via remote sensing and results in relative stability in vegetation vigour inside the delta, compared to that outside. As such the Delta acts as a regional hydro-refugium. This provides insight, not only to the potential impact of future climate in the region, but also demonstrates why similar basins are attractive to fauna, including our ancestors, in regions like eastern Africa. Although vertebrate evolution operates on time scales longer than decades, the sensitivity of rift wetlands to climate change has been stressed by some authors, and this work demonstrates another example of the unique properties that such basins can afford, given the right hydrological conditions.

10.
Iran J Public Health ; 41(8): 61-70, 2012.
Article in English | MEDLINE | ID: mdl-23113226

ABSTRACT

BACKGROUND: Welding can produce dangerous fumes containing various metals especially carcinogenic ones. Occupational exposure to welding fumes is associated with lung cancer. Therefore, welders in Gas Transmission Pipelines are known as a high-risk group. This study was designed to determinate the amounts of metals Cr, Ni, and Cd in breathing zone and urine of welders and to assess the possibility of introducing urinary metals as a biomarker due to occupational exposure. METHODS: In this cross sectional study, 94 individuals from Gas Transmission Pipelines welders, Iran, Borujen in 2011 were selected and classified into 3 groups including Welders, Back Welders and Assistances. The sampling procedures were performed according to NIOSH 7300 for total chromium, nickel, and cadmium and NIOSH 7600 for Cr+6. For all participants urine samples were collected during the entire work shift and metals in urine were determined according to NIOSH 8310. RESULTS: Back Welders and Assistances groups had maximum and minimum exposure to total fume and its elements, respectively. In addition, results showed that there are significant differences (P<0.05) between Welders and Back Welders with Assistances group in exposure with total fume and elements except Ni. Urinary concentrations of three metals including Cr, Cd and Ni among all welders were about 4.5, 12 and 14-fold greater than those detected in controls, respectively. Weak correlations were found between airborne and urinary metals concentrations (R2: Cr=0.45, Cd=0.298, Ni=0.362). CONCLUSION: Urinary metals concentrations could not be considerate as a biomarker for welders' exposure assessment.

11.
Cell Death Dis ; 2: e130, 2011 Mar 17.
Article in English | MEDLINE | ID: mdl-21412276

ABSTRACT

Signalling by receptor tyrosine kinases (RTKs) coordinates basic cellular processes during development and in adulthood. Whereas aberrant RTK signalling can lead to cancer, reactivation of RTKs is often found following stress or cell damage. This has led to the common belief that RTKs can counteract degenerative processes and so strategies to exploit them for therapy have been extensively explored. An understanding of how RTK stimuli act at cellular levels is needed, however, to evaluate their mechanism of therapeutic action. In this study, we genetically explored the biological and functional significance of enhanced signalling by the Met RTK in neurons, in the context of a neurodegenerative disease. Conditional met-transgenic mice, namely Rosa26(LacZ-stop-Met), have been engineered to trigger increased Met signalling in a temporal and tissue-specific regulated manner. Enhancing Met levels in neurons does not affect either motor neuron (MN) development or maintenance. In contrast, increased neuronal Met in amyotrophic lateral sclerosis (ALS) mice prolongs life span, retards MN loss, and ameliorates motor performance, by selectively delaying disease onset. Thus, our studies highlight the properties of RTKs to counteract toxic signals in a disease characterized by dysfunction of multiple cell types by acting in MNs. Moreover, they emphasize the relevance of genetically assessing the effectiveness of agents targeting neurons during ALS evolution.


Subject(s)
Amyotrophic Lateral Sclerosis/metabolism , Motor Neurons/metabolism , Proto-Oncogene Proteins c-met/metabolism , Signal Transduction , Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/pathology , Animals , Disease Models, Animal , Female , Humans , Male , Mice , Mice, Transgenic , Motor Neurons/pathology , Proto-Oncogene Proteins c-met/genetics
12.
J Radiol ; 91(5 Pt 1): 539-42, 2010 May.
Article in French | MEDLINE | ID: mdl-20657351

ABSTRACT

Twinkling artifact characterized by a rapidly fluctuating mixture of Doppler signals occurs behind a strongly reflecting granular interface such as urinary tract stones or gallstones. It may occurs in association with several clinical situations, and may sometimes be helpful for diagnosis while it may sometimes be a pitfall that must be recognized by the sonographer. After reviewing the technical nature of this artifact, several cases will be presented to illustrate the advantages and pitfalls related to this artifact.


Subject(s)
Artifacts , Ultrasonography, Doppler , Humans
15.
East Mediterr Health J ; 14(5): 1090-100, 2008.
Article in French | MEDLINE | ID: mdl-19161081

ABSTRACT

We studied the relationship between erectile dysfunction (ED) and diabetes among 189 men (> 40 years) attending primary health care centres in Morocco. Of the 89 diabetic men, 82% had ED while only 17% of the 100 non-diabetic men had ED. The frequency of ED among diabetic men increased with age, from 60% in those aged 40-49 years to 94.95% in those aged > or = 60 years (from 6.3% to 35.4% in men without diabetes for similar ages). ED was reported by 93.3% of diabetic men who had had diabetes for > 15 years. The frequency of ED did not differ with type of diabetes but it was significantly commoner in diabetic men with a low level of education and with hypertension.


Subject(s)
Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Erectile Dysfunction , Outpatients/statistics & numerical data , Adult , Age Distribution , Alcohol Drinking/adverse effects , Alcohol Drinking/epidemiology , Case-Control Studies , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Educational Status , Erectile Dysfunction/epidemiology , Erectile Dysfunction/etiology , Exercise , Humans , Hyperlipidemias/complications , Hyperlipidemias/epidemiology , Hypertension/complications , Hypertension/epidemiology , Male , Middle Aged , Morocco/epidemiology , Obesity/complications , Obesity/epidemiology , Population Surveillance , Prevalence , Prostatic Neoplasms/complications , Prostatic Neoplasms/epidemiology , Risk Factors , Severity of Illness Index , Smoking/adverse effects , Smoking/epidemiology
16.
(East. Mediterr. health j).
in French | WHO IRIS | ID: who-117532

ABSTRACT

We studied the relationship between erectile dysfunction [ED] and diabetes among 189 men [> 40 years] attending primary health care centres in Morocco. Of the 89 diabetic men, 82% had ED while only 17% of the 100 non-diabetic men had ED. The frequency of ED among diabetic men increased with age, from 60% in those aged 40-49 years to 94.95% in those aged >/= 60 years [from 6.3% to 35.4% in men without diabetes for similar ages]. ED was reported by 93.3% of diabetic men who had had diabetes for > 15 years. The frequency of ED did not differ with type of diabetes but it was significantly commoner in diabetic men with a low level of education and with hypertension


Subject(s)
Erectile Dysfunction , Epidemiology , Age Factors , Hypertension , Educational Status , Smoking , Diabetes Complications
18.
Diagn Cytopathol ; 29(4): 185-93, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14506669

ABSTRACT

Fine-needle aspiration cytology (FNAC) is a widely practiced technique in the diagnosis of breast carcinoma, and it is the only diagnostic procedure performed before definitive treatment, at most institutions. While the histological grading of breast carcinoma has become routine in many centers worldwide, the cytopathological grading of breast carcinoma is not commonly used. Grading of breast carcinoma, while the tumor is still in vivo, would be the most ideal and desirable situation, as it would be helpful in the selection of patients for appropriate therapy. The objective of this study, therefore, was to devise a simple system for grading breast carcinoma, based on the cytological features alone. We reviewed 125 cases of breast carcinoma retrospectively, which were initially diagnosed by FNAC, with subsequent histopathological confirmation. These included 105 ductal, 6 lobular, 2 tubular, 1 papillary, and 1 medullary carcinoma. There was 1 ductal carcinoma in situ. Nine cases were rendered insufficient for grading. Thus 105 cases of ductal carcinoma (NOS) were evaluated for final cytological grading. Air-dried Diff-Quik-stained smears were reviewed at least twice independently by four histopathologists and were then compared with the original histological grades. Six cytological features used for grading were found to be statistically significant: cellular pleomorphism, nuclear size, nuclear margin, nucleoli, naked tumor nuclei, and mitoses. A scoring system based on these six essential parameters was used, to classify ductal carcinoma into three cytological grades, which showed close correlation with the established histological grades. In addition, two less consistent, but still important, features were the presence or absence of necrosis and stromal invasion. Another six parameters, including smear cellularity, degree of cell dispersion or clustering, lymphoplasmacytic infiltrate, presence of tubular structures, cytoplasmic appearance of the tumor cells, and smear background, were not statistically significant. However, these additional parameters were found helpful in assigning the correct grade, in cases with borderline scores. The concordance rate with histology was 100% for grade 1, 98% for grade 2, and 93% for grade 3.


Subject(s)
Biopsy, Fine-Needle/methods , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/pathology , Staining and Labeling , Breast Neoplasms/classification , Carcinoma, Ductal, Breast/classification , Female , Humans , Neoplasm Staging , Retrospective Studies
19.
J Neuroendocrinol ; 15(8): 754-60, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12834436

ABSTRACT

Neuropeptide Y (NPY)-expressing neurones in the arcuate nucleus densely innervate many hypothalamic nuclei. To determine the neurochemical phenotype of target neurones for NPY, we studied the immunohistochemical localization of the NPY Y1 receptor (Y1R) in discrete subpopulations of neurones in the rat hypothalamus. Among several tested populations, including hypocretin/orexin-, melanin-concentrating hormone (MCH)- and nitric oxide synthase (NOS)-positive neurones, only the latter were found to coexpress the Y1R. Numerous Y1R/NOS-positive neurones were found as a densely packaged group of cells located ventrolateral to the ventromedial nucleus, forming a band ascending towards the fornix. Lower numbers of Y1R/NOS-positive neurones were found in the perifornical area and in the peri- and paraventricular nuclei. Expression of the Y1R gene was found in the same locations in the mouse by colocalizing beta-galactosidase, a Y1R gene reporter, with NOS in a Y1R knockout mouse. To explore possible downstream targets of NO in the rat hypothalamus, the NO-regulated molecule cGMP was analysed immunohistochemically after incubation of brain slices with sodium nitroprusside, an NO donor. We observed several cGMP-positive cell bodies in the arcuate nucleus, cGMP-positive blood vessels and a cGMP-positive network of thin fibres, some of which colocalized with choline acetyltransferase.


Subject(s)
Neuropeptide Y/metabolism , Nitric Oxide/metabolism , Receptors, Neuropeptide Y/metabolism , Ventromedial Hypothalamic Nucleus/metabolism , Animals , Cyclic GMP/metabolism , Eating/physiology , Energy Metabolism/physiology , Immunohistochemistry , Male , Mice , Mice, Knockout , Neurons/metabolism , Rats , Rats, Sprague-Dawley , Receptors, Neuropeptide Y/genetics , Ventromedial Hypothalamic Nucleus/cytology
20.
Nature ; 409(6823): 1023-6, 2001 Feb 22.
Article in English | MEDLINE | ID: mdl-11234007

ABSTRACT

Materials containing organic-inorganic interfaces usually display a combination of molecular and solid-state properties, which are of interest for applications ranging from chemical sensing to microelectronics and catalysis. Thiols--organic compounds carrying a SH group--are widely used to anchor organic layers to gold surfaces, because gold is catalytically sufficiently active to replace relatively weak S-H bonds with Au-S bonds, yet too inert to attack C-C and C-H bonds in the organic layer. But although several methods of functionalizing the surfaces of semiconductors, oxides and metals are known, it remains difficult to attach a wide range of more complex organic species. Organic layers could, in principle, be formed on the surfaces of metals that are capable of inserting into strong bonds, but such surfaces catalyse the decomposition of organic layers at temperatures above 400 to 600 K, through progressive C-H and C-C bond breaking. Here we report that cycloketones adsorbed on molybdenum carbide, a material known to catalyse a variety of hydrocarbon conversion reactions, transform into surface-bound alkylidenes stable to above 900 K. We expect that this chemistry can be used to create a wide range of exceptionally stable organic layers on molybdenum carbide.

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