Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 71
Filter
1.
Sci Rep ; 14(1): 11677, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38778124

ABSTRACT

The potential for manipulating characteristics of skyrmions in a CrI 3 monolayer using circularly polarised light is explored. The effective skyrmion-light interaction is mediated by bright excitons whose magnetization is selectively influenced by the polarization of photons. The light-induced skyrmion dynamics is illustrated by the dependencies of the skyrmion size and the skyrmion lifetime on the intensity and polarization of the incident light pulse. Two-dimensional magnets hosting excitons thus represent a promising platform for the control of topological magnetic structures by light.

2.
Opt Express ; 31(9): 15045-15057, 2023 Apr 24.
Article in English | MEDLINE | ID: mdl-37157355

ABSTRACT

The performance of modular, networked quantum technologies will be strongly dependent upon the quality of their quantum light-matter interconnects. Solid-state colour centres, and in particular T centres in silicon, offer competitive technological and commercial advantages as the basis for quantum networking technologies and distributed quantum computing. These newly rediscovered silicon defects offer direct telecommunications-band photonic emission, long-lived electron and nuclear spin qubits, and proven native integration into industry-standard, CMOS-compatible, silicon-on-insulator (SOI) photonic chips at scale. Here we demonstrate further levels of integration by characterizing T centre spin ensembles in single-mode waveguides in SOI. In addition to measuring long spin T1 times, we report on the integrated centres' optical properties. We find that the narrow homogeneous linewidth of these waveguide-integrated emitters is already sufficiently low to predict the future success of remote spin-entangling protocols with only modest cavity Purcell enhancements. We show that further improvements may still be possible by measuring nearly lifetime-limited homogeneous linewidths in isotopically pure bulk crystals. In each case the measured linewidths are more than an order of magnitude lower than previously reported and further support the view that high-performance, large-scale distributed quantum technologies based upon T centres in silicon may be attainable in the near term.

3.
Arch Razi Inst ; 77(1): 503-511, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35891755

ABSTRACT

Today, the production of extremely low-frequency electromagnetic fields (ELF-EMFs) has significantly increased. This study aimed to investigate the effect of the ELF-EMFs on the structure and function of the brain in male rhesus monkeys in terms of visual learning (VL), visual memory (VM), and visual working memory (VWM). To conduct the study, four monkeys were selected, of whom two monkeys were irradiated by 12-Hz ELF-EMFs with a magnitude of 0.7 microtesla, and two monkeys were tested without irradiation (control group). A blood sample was taken in three stages, namely pre- and post-irradiated and the recovery phases. Changes in the plasma levels of sodium, potassium, and adrenocorticotropic hormone (ACTH) were evaluated. Moreover, gene expression of N-methyl-D-aspartate (NMDA) receptors was assessed. The anatomical change of the brain's prefrontal area was measured by magnetic resonance imaging and Digital Imaging and Communications in Medicine LiteBox file. The abilities of VL, VM, and VWM significantly improved after the irradiation. Furthermore, the expression of the NMDA receptors gene and the plasma levels of sodium, potassium, and ACTH significantly enhanced after the irradiation. However, the prefrontal area was not significantly affected by the irradiation. No significant differences were observed in any of the studied factors in the control group. Our findings suggested that ELF-EMFs irradiation at 12 Hz positively affected VL and VWM. Consequently, 12-Hz ELF-EMFs irradiations can be widely applied to improve cognitive abilities in monkeys.


Subject(s)
Adrenocorticotropic Hormone , Electromagnetic Fields , Male , Animals , Sodium , Cognition , Potassium
4.
Arch Razi Inst ; 77(1): 37-44, 2022 02.
Article in English | MEDLINE | ID: mdl-35891774

ABSTRACT

Foot-and-mouth disease (FMD) is an acute and highly contagious disease in livestock, such as cattle, sheep, and pigs, leading to a lot of economic losses. The current FMD vaccines formulated by inactivated whole-virus and adjuvant successfully reduce disease outbreaks in many regions of the world. Immunological studies on FMD viruses revealed that the dominant epitope in arising neutral antibody response is amino acid residues constructing the G-H loop, constituting a surface loop of the structural protein, termed VP1. Liposomes as one of the most well-known vehicles are considered an important carrier in vaccine development, and their function is used to encapsulate purified VP1 protein based on their size, charge, and lipid content. Accordingly, the VP1 protein was isolated from the FMD virus. This study aimed to compare four methods of VP1 protein encapsulation in the liposome and the extruding effect, as follows: 1) VP1 protein was dissolved in dimethyl sulfoxide and added to the lipid film hydrated by ethanol, 2) the lipid film was hydrated by VP1 protein with 7M urea, 3) the lipid film was hydrated by VP1 protein and freeze-thawed, and 4) the lipid film was hydrated by VP1 protein. The highest encapsulation efficiency was 91% in the second method which purified protein-containing urea. The VP1 protein in the prepared liposome (1, 2-dimyristoyl-sn-glycero-3-phosphocholine: 1, 2-dimyristoyl-sn-glycero-3-phosphocholine: cholesterol) released more than 90% of protein content after 240 h.


Subject(s)
Cattle Diseases , Foot-and-Mouth Disease Virus , Foot-and-Mouth Disease , Sheep Diseases , Swine Diseases , Viral Vaccines , Animals , Antibodies, Viral , Capsid Proteins , Cattle , Cattle Diseases/prevention & control , Foot-and-Mouth Disease/prevention & control , Lipids , Liposomes , Phosphorylcholine , Sheep , Swine , Swine Diseases/prevention & control , Urea
5.
Arch Razi Inst ; 77(4): 1397-1403, 2022 08.
Article in English | MEDLINE | ID: mdl-36883163

ABSTRACT

Video games have significant and diverse effects on stress and cognitive systems based on the game style. The effect of this media on the central nervous system is significant because of its repetition. Nowadays, video games have become an important part of human life at different ages, and therefore, assessing their effects (good and bad) on stress factors, cognition, and behavior can be an important help in understanding the nature of these games and managing their impact on humans. Consequently, this study aimed to investigate the effect of a puzzle game on the player's stress and cognitive indicators in neuropsychological, biochemical, and electrophysiological approaches. A total of 44 participants were entered into the study and randomly assigned to control and experimental groups. Our interventions were watching (control group) and playing (experimental group) the game. Salivary biomarkers (cortisol and alpha-amylase) were measured using the enzyme-linked immunosorbent assay method. Electrophysiological assessment of attention and stress was performed using electroencephalography. Neuropsychological assessments for the evaluation of mental health, mental fatigue, sustained attention, and reaction time were conducted using paced auditory serial addition test. All tests were administered before and after the interventions. The findings revealed that the salivary cortisol and alpha-amylase significantly reduced after playing the game. There were significantly higher levels of attention after playing the game. Mental health and sustained attention significantly increased after game playing. It can conclude that puzzle-style computer games can strengthen and empower the perceptual-cognitive system and suppress the stress system of players. Therefore, they can be used purposefully as a positive cognitive therapy approach.


Subject(s)
Cognition , Hydrocortisone , Humans , alpha-Amylases , Enzyme-Linked Immunosorbent Assay
6.
Nat Commun ; 12(1): 6107, 2021 Oct 20.
Article in English | MEDLINE | ID: mdl-34671016

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) play an important role in interstellar chemistry and are subject to high energy photons that can induce excitation, ionization, and fragmentation. Previous studies have demonstrated electronic relaxation of parent PAH monocations over 10-100 femtoseconds as a result of beyond-Born-Oppenheimer coupling between the electronic and nuclear dynamics. Here, we investigate three PAH molecules: fluorene, phenanthrene, and pyrene, using ultrafast XUV and IR laser pulses. Simultaneous measurements of the ion yields, ion momenta, and electron momenta as a function of laser pulse delay allow a detailed insight into the various molecular processes. We report relaxation times for the electronically excited PAH*, PAH+* and PAH2+* states, and show the time-dependent conversion between fragmentation pathways. Additionally, using recoil-frame covariance analysis between ion images, we demonstrate that the dissociation of the PAH2+ ions favors reaction pathways involving two-body breakup and/or loss of neutral fragments totaling an even number of carbon atoms.

7.
Arch Razi Inst ; 76(2): 335-344, 2021 07.
Article in English | MEDLINE | ID: mdl-34223732

ABSTRACT

This study conducted two experiments to evaluate the effects of two cheap adsorbents, including bentofeed (a commercial name of bentonite) and Persian melon peel biochar (PMPB) on the decolorization of water contaminated by methylene blue (MB) and ruminal fermentation pattern. The decolorization efficiency of bentofeed and PMPB at three levels of 0, 4, and 8 mg per 10 ml of 0, 3, 6, and 9 mg/L MB solutions mg/L after 3 and 24 h of incubation was evaluated by its absorbance at 660 nm. At all dye concentrations, PMPB, and bentofeed showed high potential in removing MB from water with an efficiency of 60%-99.5%. In both incubation times, the addition of 8 mg bentofeed had the highest effect on the removal efficiency when the dye concentration was 6 or 9 mg/L. However, the removal efficiency was declined with increasing MB concentration (p <0.05). Experiment two evaluated the effects of various levels (same as experiment one) of MB, bentofeed, and PMPB on in vitro gas production (GP) and volatile fatty acids (VFA) in two individual 4×3 factorial experiments. The potential GP (b), rate constant of gas production (c), metabolizable energy, organic matter digestibility, and total VFA were significantly decreased with increasing MB in the medium (p <0.05), while all parameters were increased when bentofeed or PMPB was added to the medium containing MB (p <0.05). The amounts of acetic, propionic, and butyric acids were not affected by PMPB; however, they changed when bentofeed was added to the medium (p <0.05). The NH3-N concentration was decreased significantly following the increase of MB; moreover, it was increased when PMPB and bentofeed were added to the medium. MB, as a water contaminant agent, had negative effects on ruminal fermentation parameters. Both adsorbents (i.e., PMPB and specially bentofeed) were efficiently able to remove MB from the water. The negative effects of MB on fermentation parameters were also alleviated as a result of using bentofeed or PMPB. It seems that bentofeed has the higher adsorption property of MB, compared to that of the PMPB.


Subject(s)
Cucurbitaceae , Rumen , Animal Feed/analysis , Animals , Charcoal , Fermentation , Methylene Blue/metabolism , Water/metabolism
9.
Ann Ig ; 33(2): 177-188, 2021.
Article in English | MEDLINE | ID: mdl-33570089

ABSTRACT

BACKGROUND: Length of hospitalization is one of the most important indices in evaluating the efficiency and effectiveness of hospitals and the optimal use of resources. Identifying these indices' associated factors could be useful. This study aimed to investigate effective factors of the length of hospitalization in Zanjan teaching hospitals in 2018 using the Quantile regression model. METHODS: This cross-sectional study was conducted on 1,031 patients. The study population consisted of patients in orthopaedic, pediatric, internal, surgical and intensive care units. The samples were selected by multistage random sampling. The information was collected by a pre-designed checklist. The Quantile regression model and ordinary regression model were performed on the data. RESULTS: Of the 1,031 patients admitted to different units, 624 (60.52%) were male. Mean and standard deviation of length of hospitalization for men, women and all patients were 7.25±5.48, 8.09±6.35 and 7.58±5.83 respectively. For 90 percent of patients the length of hospitalization was less than 14 days. Twenty-five percent of patients in pediatric and orthopedic units and ten percent of patients in internal and surgery units were hospitalized less than three days. In all quantiles, patients' length of hospitalization in surgery and orthopedic units, compared to the intensive care unit, and patients hospitalized for injuries and poisonings compared to other causes, had a statistically significant difference. (p<0.05). CONCLUSION: Due to the heterogeneity (skewness) of the length of hospital stay in different units of the hospital, the quantile regression model predicts the length of hospital stay more precisely than the ordinary regression models.


Subject(s)
Hospitalization , Intensive Care Units , Child , Cross-Sectional Studies , Female , Hospitals, Teaching , Humans , Length of Stay , Male
10.
Prog Biophys Mol Biol ; 164: 92-100, 2021 09.
Article in English | MEDLINE | ID: mdl-33450244

ABSTRACT

Cryo-electron microscopy using single particle analysis requires the computational averaging of thousands of projection images captured from identical macromolecules. However, macromolecules usually present some degree of flexibility showing different conformations. Computational approaches are then required to classify heterogeneous single particle images into homogeneous sets corresponding to different structural states. Nonetheless, sometimes the attainable resolution of reconstructions obtained from these smaller homogeneous sets is compromised because of reduced number of particles or lack of images at certain macromolecular orientations. In these situations, the current solution to improve map resolution is returning to the electron microscope and collect more data. In this work, we present a fast approach to partially overcome this limitation for heterogeneous data sets. Our method is based on deforming and then moving particles between different conformations using an optical flow approach. Particles are then merged into a unique conformation obtaining reconstructions with improved resolution, contrast and signal-to-noise ratio. We present experimental results that show clear improvements in the quality of obtained 3D maps, however, there are also limits to this approach, i.e., the method is restricted to small deformations and cannot determine local patterns of flexibility of small elements, such as secondary structures, which we discuss in the manuscript.


Subject(s)
Imaging, Three-Dimensional , Cryoelectron Microscopy , Macromolecular Substances , Protein Structure, Secondary , Signal-To-Noise Ratio
11.
Bratisl Lek Listy ; 122(1): 54-64, 2021.
Article in English | MEDLINE | ID: mdl-33393322

ABSTRACT

The effect of poly(lactic­co­glycolic acid) (PLGA) on structure, degradation, drug release and mechanical properties of fibrin/pomegranate(F/POM)-based drug­eluting scaffolds have been studied comprehensively. METHODS AND MATERIAL: Nanoparticle-fibrin is prepared from thrombin and fibrinogen dissolved in NaOH and HCl. Then pomegranate powder is added to it. Nanoparticles/pom are provided by freeze drying and freeze milling. The 3-D scaffold of poly(lactide-co­glycolic acid) (PLGA) was prepared via salt­leaching solvent/casting leaching method and impregnated with nanofibrin-pom. Structural and chemical component of the scaffolds were evaluated by transmission and scanning electron microscopy and furrier transmission infrared spectroscopy, respectively. Moreover, the scaffolds were characterized from the degradation rate and drug releasing rate points of view of human Adipose Derive Stem Cells (hADSCs). Cytotoxicity effects of the scaffold were evaluated on hADSCs via MTT assay. RESULTS: The results showed that the size of nanoparticles was about 100 nm. The scaffold had a slow degradation rate and it caused a sustained release pattern of pom. MTT assay indicated that nanoparticles had no cytotoxicity and fibrin-pom nanoparticles increased compressive strength of PLGA/scaffolds dramatically and also caused a proper compressive modulus. CONCLUSIONS: By adding F/POM nanoparticle to PLGA and fabricating a three­dimensional nanocomposite scaffold (PLGA/F/POM nanoparticle), special physical and mechanical properties also suitable for drug release and cell behavior were achieved, which makes it suitable for cartilage tissue engineering applications (Tab. 1, Fig. 7, Ref. 53) Keywords: hybrid composites, drug delivery, carrier, nanoparticles, scaffold.


Subject(s)
Nanocomposites , Fibrin , Glycols , Humans , Polylactic Acid-Polyglycolic Acid Copolymer , Pomegranate , Tissue Engineering , Tissue Scaffolds
12.
Arch Razi Inst ; 76(5): 1183-1190, 2021 11.
Article in English | MEDLINE | ID: mdl-35355777

ABSTRACT

Foot-and-mouth disease (FMD) is a highly contagious viral disease affecting cloven-hoofed animals. The particular virus causing FMD disease is called FMD virus and is a member of the Aphthovirus genus in the Picornaviridae family. The FMD virus has an 8500 nt long single strain positive RNA genome with one open reading frame (ORF) trapped in an icosahedral capsid protein. This virus genome doesn't have proofreading property which leads to high mutagenesis. It has seven serotypes, including O, A, ASIA, SAT1, SAT2, and C serotypes, as well as many subtypes. Iran is an endemic region for foot-and-mouth disease. Vaccination of susceptible animals with an inactivated whole-virus vaccine is the only way to control the epidemic in many developing countries. Today, conventionally attenuated and killed virus vaccines are being used worldwide. In Iran, animals have been vaccinated every 105 days with an inactivated FMD vaccine. Although commercially available FMD vaccines are effective, they provide short-term immunity requiring regular boosters. A new FMD vaccine is needed to improve immunization, safety, and long-term immune responses. A synthetic peptide vaccine is one of the safe and important vaccines. Peptide vaccine has low immunogenicity, requiring strong adjuvants. Nanoliposomes can be used as new adjuvants to improve immune response. In the current study, nanoliposomal carriers were selected using Dimyristoylphosphatidylcholine (DMPC), dimyristoyl phosphoglycerol (DMPG), and Cholesterol (Chol) as an adjuvant containing two immunodominant synthetic FMDV peptides. The liposomal formulations were characterized by various physicochemical properties. The size, zeta potential, and encapsulation efficiency were optimized, and the obtained nanoliposome was suitable as a vaccine. The efficacy of vaccines has been evaluated in guinea pigs as animal models. Indirect ELISA was used to detect FMDV-specific IgG. The obtained results indicated that although antibody titer was observed, the amount was lower compared to the groups that received inactivated virus-containing liposomes. In addition, the results showed that liposome was an appropriate adjuvant, compared to other adjuvants, such as Alum and Freund, and can act as a depot and induce an immune response.


Subject(s)
Foot-and-Mouth Disease Virus , Foot-and-Mouth Disease , Viral Vaccines , Animals , Foot-and-Mouth Disease/prevention & control , Guinea Pigs , Peptides , Vaccines, Inactivated
13.
Osteoporos Int ; 31(9): 1671-1682, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32361950

ABSTRACT

The relationship between heavy metal exposure and risk of osteopenia or osteoporosis has biological plausibility, yet it remains inconclusive; therefore, we conducted a systematic review and meta-analysis to evaluate the associations between exposure to heavy metals (i.e., cadmium, lead, and mercury) and the risk of osteopenia or osteoporosis. Databases of MEDLINE, Embase, Scopus, and Web of Science were searched through November 2019, to identify studies that evaluated the relationship between exposure to cadmium, lead, and mercury and risk of osteopenia or osteoporosis in adults. Fourteen eligible studies were included. Effect sizes expressed as pooled odds ratios (OR) and 95% confidence intervals (CI) were estimated using weighted random-effect models. Exposure to cadmium (OR = 1.35; 95% CI: 1.17 to 1.56; P ≤ 0.001) and lead (OR = 1.15; 95% CI: 1.00 to 1.32; P = 0.05) was associated with an increased risk of osteopenia or osteoporosis, unlike mercury. Subgroup analyses showed cadmium exposure increased the risk of osteopenia or osteoporosis in older (> 65 yrs.; OR = 1.43; 95%CI: 1.08 to 1.88, P = 0.01) compared with younger (18-65 yrs.; OR = 1.24; 95% CI: 1.02 to 1.52, P = 0.03) adults. Also, lead exposure increased the risk in men (OR = 1.55; 95% CI: 1.15 to 2.09, P = 0.007) unlike in women. By contrast to urinary levels, blood (OR = 1.26; 95% CI: 1.08 to 1.47, P = 0.003) and dietary (OR = 1.46; 95% CI: 1.28 to 1.67, P < 0.001) levels of cadmium were associated with an increased risk of osteopenia or osteoporosis. Exposure to cadmium and lead may be associated with an increased risk of osteopenia or osteoporosis, although high heterogeneity was detected.


Subject(s)
Bone Diseases, Metabolic , Mercury , Metals, Heavy , Osteoporosis , Adult , Aged , Bone Diseases, Metabolic/chemically induced , Bone Diseases, Metabolic/epidemiology , Cadmium/toxicity , Female , Humans , Male , Mercury/toxicity , Metals, Heavy/toxicity , Osteoporosis/chemically induced , Osteoporosis/epidemiology
14.
Nanoscale Adv ; 2(4): 1560-1572, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-36132302

ABSTRACT

The combination of ionic liquid and nanoparticle properties is highly appealing for a number of applications. However, thus far there has been limited systematic exploration of colloidal stabilisation in these solvents, which provides an initial direction towards their employment. Here, we present a new and comprehensive study of the key parameters affecting the colloidal stability in dispersions of oxide nanoparticles in ionic liquids. Twelve diverse and representative ionic liquids are used to disperse iron oxide nanoparticles. The liquid interface of these nanoparticles has been carefully tuned in a molecular solvent before transferring into an ionic liquid, without passing through the powder state. Multiscale-characterisation is applied, on both the micro and the nano scale, incorporating both small angle X-ray scattering and dynamic light scattering. The results show the surface charge of the nanoparticles to be a crucial parameter, controlling the layering of the surrounding ionic liquid, and hence producing repulsion allowing efficient counterbalancing of the attractive interactions. For intermediate charges the strength of the repulsion depends on the specific system causing varying levels of aggregation or even none at all. Several samples consist of sufficiently repulsive systems leading to single dispersed nanoparticles, stable in the long term. Thanks to the magnetic properties of the chosen iron oxide nanoparticles, true ferrofluids are produced, appropriate for applications using magnetic fields. The strength and breadth of the observed trends suggests that the key parameters identified here can be generalised to most ionic liquids.

15.
Opt Express ; 27(9): 13479-13491, 2019 Apr 29.
Article in English | MEDLINE | ID: mdl-31052869

ABSTRACT

We present the design of an extreme ultraviolet (XUV) pulse shaper relying on reflective optics. The instrument will allow tailoring of the time-frequency spectrum of femtosecond pulses generated by seeded free-electron lasers (FEL) and high-harmonic generation (HHG) sources down to a central wavelength of ~15 nm. The device is based on the geometry of a 4f grating compressor that is a standard concept in ultrafast laser science and technology. We apply it to shorter wavelengths using grazing-incidence optics operated under ultra-high vacuum conditions. The design blaze angle and the line density of the gratings allow the manipulation of all different harmonics typical for seeded FEL and HHG photon sources without the need of realignment of the instrument and even simultaneously in multi-color experiments. A proof-of-principle pulse shaping experiment using 266 nm laser light has been performed, demonstrating relative phase-control of femtosecond UV pulses.

16.
ISA Trans ; 94: 338-351, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31079876

ABSTRACT

In this paper, a new Fault Detection (FD) scheme based on combination of switching observer and Bond Graph (BG) method for linear continuous time switched systems with Average Dwell Time (ADT) approach is proposed. The proposed scheme is a BG-based two-stage FD system in which the compact state space representation and Global Analytical Redundancy Relations (GARRs) are derived based on the BG model. In the first stage, a switched observer is designed considering disturbance attenuation level, fault sensitivity and rapid fault detection criteria by solving a weighted Linear Matrix Inequality (LMI) optimization problem. Next, a new form of GARRs which is based on output estimation error of the observer and is called Error-based Global Analytical Redundancy Relations (EGARRs) is developed to combine the observer and BG method. The output estimation errors from the observer, which are adequately sensitive to faults and simultaneously the effects of disturbances are attenuated therein, are given to the EGARRs to generate the residuals of the FD system. The proposed method may be used for fault detection of switched linear systems with ADT based on the BG model of the system. Finally, two case studies including a two-tank system and a buck converter-driven DC motor are considered to show the efficiency and real-time implementation of the proposed method.

17.
J Struct Biol ; 204(3): 527-542, 2018 12.
Article in English | MEDLINE | ID: mdl-30273658

ABSTRACT

This document presents the analysis performed over the Map Challenge dataset using a new algorithm which we refer to as Pair Comparison Method. The new algorithm, which is described in detail in the text, is able to sort reconstructions based on a figure of merit and assigns a level of significance to the sorting. That is, it shows how likely the sorting is due to chance or if it reflects real differences.


Subject(s)
Algorithms , Fourier Analysis , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Microscopy, Electron/methods , Proteasome Endopeptidase Complex/metabolism , Proteasome Endopeptidase Complex/ultrastructure , Ribosomes/metabolism , Ribosomes/ultrastructure
18.
Biomed Res Int ; 2017: 6482567, 2017.
Article in English | MEDLINE | ID: mdl-29312997

ABSTRACT

One of the key steps in Electron Microscopy is the tomographic reconstruction of a three-dimensional (3D) map of the specimen being studied from a set of two-dimensional (2D) projections acquired at the microscope. This tomographic reconstruction may be performed with different reconstruction algorithms that can be grouped into several large families: direct Fourier inversion methods, back-projection methods, Radon methods, or iterative algorithms. In this review, we focus on the latter family of algorithms, explaining the mathematical rationale behind the different algorithms in this family as they have been introduced in the field of Electron Microscopy. We cover their use in Single Particle Analysis (SPA) as well as in Electron Tomography (ET).


Subject(s)
Algorithms , Imaging, Three-Dimensional/methods , Microscopy, Electron/methods , Humans
19.
Andrologia ; 49(8)2017 Oct.
Article in English | MEDLINE | ID: mdl-27905126

ABSTRACT

This study was established a model of obesity to estimate the impact of fennel and cumin as anti-obesity extracts on body weight, body mass index (BMI), food consumption, leptin concentration, sperm quality and testis architecture to determine the reversibility of reproductive function of obese animals. Male rats were randomly assigned to either a normal or high-fat diet for 8 weeks. Then, we divided 56 adult rats into seven groups: control (CO); obesity (OB); fennel 100 and 200 mg/kg; cumin 50 and 100 mg/kg; and fennel 100 mg/kg plus cumin 50 mg/kg. From weeks 9-16, the animals treated extracts by gavages daily. We analysed leptin concentration, sperm quality and apoptosis of testis along with evaluating changes in body weight. Body weight of animals increased 25% at week 8. However, body weight, BMI, leptin concentration and apoptosis indices of OB rats increased at the end of study. However, the relative sperm parameters decreased. Nevertheless, fennel and cumin treatment improved sperm quality, and spermatogenic cells apoptosis following weight loss. Concomitant with weight loss, leptin concentration and food consumption decreased. In conclusion, fennel and cumin as supplements may ameliorate sperm quality of obese animals following weight loss and reduction in leptin concentration.


Subject(s)
Apoptosis/drug effects , Cuminum , Foeniculum , Leptin/blood , Obesity/metabolism , Plant Extracts/pharmacology , Spermatozoa/drug effects , Weight Loss/drug effects , Animals , Body Weight/drug effects , Diet, High-Fat , Male , Obesity/blood , Rats , Rats, Wistar , Semen Analysis , Spermatogenesis/drug effects , Spermatozoa/metabolism , Testis/drug effects , Testis/metabolism
20.
Andrologia ; 49(3)2017 Apr.
Article in English | MEDLINE | ID: mdl-27246506

ABSTRACT

Korean red ginseng (KRG) may be a beneficial adjuvant along with ciprofloxacin to ameliorate devastating effects of epididymo-orchitis (EO) on male fertility. This study intends to assay the effects of KRG and ciprofloxacin on sperm quality and spermatogenic cells apoptosis in EO rats. We divided 54 adult rats into nine groups (n = 6 rats per group): control (CO), sham-operated (SH), EO (E); ciprofloxacin (C), EO-ciprofloxacin (EC), KRG (G), EO-KRG (EG), ciprofloxacin-KRG (CG) and EO-ciprofloxacin-KRG (ECG). We administered ciprofloxacin and KRG 48 hr after the Escherichia coli (E. coli) injection for 10 days. Bilateral orchiectomy was performed after one sperm cycle (14 days) following the last treatment with ciprofloxacin and KRG. Total and progressive motility of E, C and EC groups decreased. However, motility is improved in CG and ECG in comparison with these groups. The E group induced negative changes in the architecture of testes tissue and dramatic increase in apoptosis indices. Interestingly, co-administration of ciprofloxacin and KRG has dramatically improved Miller's and Johnsen's scores and decreased the apoptosis indices of animals in the ECG group. Combined treatment of ciprofloxacin and KRG may improve the quality of spermatozoa and attenuated apoptosis indices in the ECG group.


Subject(s)
Anti-Bacterial Agents/adverse effects , Ciprofloxacin/adverse effects , Epididymitis/drug therapy , Orchitis/drug therapy , Panax/chemistry , Plant Extracts/therapeutic use , Sperm Motility/drug effects , Animals , Anti-Bacterial Agents/therapeutic use , Apoptosis/drug effects , Ciprofloxacin/therapeutic use , Disease Models, Animal , Epididymitis/complications , Epididymitis/microbiology , Escherichia coli/isolation & purification , Escherichia coli Infections/complications , Escherichia coli Infections/drug therapy , Escherichia coli Infections/microbiology , Humans , Male , Orchitis/complications , Orchitis/microbiology , Rats , Rats, Wistar , Spermatozoa/drug effects
SELECTION OF CITATIONS
SEARCH DETAIL