Multiple morphological abnormalities of the flagella (MMAF) is a severe disease of male infertility, while the pathogenetic mechanisms of MMAF are still incompletely understood. Previously, we found ...that the deficiency of
Ccdc38
might be associated with MMAF. To understand the underlying mechanism of this disease, we identified the potential partner of this protein and found that the coiled-coil domain containing 146 (CCDC146) can interact with CCDC38. It is predominantly expressed in the testes, and the knockout of this gene resulted in complete infertility in male mice but not in females. The knockout of
Ccdc146
impaired spermiogenesis, mainly due to flagellum and manchette organization defects, finally led to MMAF-like phenotype. Furthermore, we demonstrated that CCDC146 could interact with both CCDC38 and CCDC42. It also interacts with intraflagellar transport (IFT) complexes IFT88 and IFT20. The knockout of this gene led to the decrease of ODF2, IFT88, and IFT20 protein levels, but did not affect CCDC38, CCDC42, or ODF1 expression. Additionally, we predicted and validated the detailed interactions between CCDC146 and CCDC38 or CCDC42, and built the interaction models at the atomic level. Our results suggest that the testis predominantly expressed gene
Ccdc146
is essential for sperm flagellum biogenesis and male fertility, and its mutations might be associated with MMAF in some patients.
Linepipe steels fabricated using thermo-mechanically controlled processes exhibit microstructural inhomogeneity and a characteristic texture; therefore, they often lead to anisotropic yield strength ...properties. Although yield strength anisotropy is considered as a major guaranteed property, particularly in pipe forming processes, systematic verification of the dominant microstructural component affecting the yield strength is challenging owing to complicated microstructures and inhomogeneous distributions. In this study, the microstructures were controlled by varying the rolling reduction ratios and start rolling temperatures, specifically for polygonal ferrite (PF) and granular bainite (GB); the Taylor factor (TF) and orientation distribution function (ODF) of each microstructure were quantitatively analyzed by electron backscatter diffraction to study the effects of microstructural characteristics on the yield strength. The deviation of TF with tensile direction in GB was larger than that in PF; the intensity of {113} components in ODF maps was greater in GB than in PF. The results indicated that GB induced more yield strength anisotropy than PF; thus, steels with a greater GB fraction exhibited greater yield strength anisotropy. This study can be used for lowering the yield strength anisotropy in linepipe steel plate design, with promising prospects for wider industrialization of high-strength linepipe steels.
The possible application of a hot-melt ram extrusion printing to the preparation of diclofenac orodispersible films (ODF) made of maltodextrin was studied focusing the attention on the effects of ...taste-masking agents (i.e. namely mint, licorice-mint, and sucralose) and an opacifier (titanium dioxide TiO
2
).
This is a proof-of-concept of the feasibility to print ODF loaded with a thermosensitive drug substance by hot-melt technologies.
Diclofenac sodium (DNa) ODF made of maltodextrin (dextrose equivalent (DE) = 6 ) plasticized with glycerol were prepared by hot-melt extrusion printing. ODF were characterized for disintegration time, drug content, and solid state, in vitro dissolution in deionized water and simulated salivary fluid at pH 5.7, tensile, and adhesive properties. Moreover, the stability of ODF was assessed in accelerated conditions over six months.
After the preparation, no variation in drug solid state was evident and the formation of impurity A of DNa was detected, even if it remained below the Pharmacopoeia (Ph. Eur.) limits (< 0.2%). Only the addition of DNa significantly improved the ODF tensile properties: the tensile strength increased from 0.17 ± 0.03 MPa (placebo ODF) to 2.21 ± 0.54 MPa (p ≤ 0.03). All ODF disintegrated in about 1 min, and the t
80%
was lower than 3 min. TiO
2
reduced the static and dynamic peel forces (p ≤ 0.006) favoring the ODF detachment from the primary packaging material. During the accelerated stability study, ODF were easy to handle without fracture; the drug content, impurity A, and dissolution profiles remained superimposable.
Hot-melt printing can be suitable to prepare palatable ODF loaded with bitter thermosensitive drugs.
Grain-oriented electrical steels (GOES) are widely used in transformers to increase energy efficiency while reducing the volume and weight of such transformers. These GOES are characterized by their ...strong anisotropy, which leads to different magnetic properties (behavior law and iron losses) depending on the strength and the direction of the applied magnetic field to the rolling direction (RD). To describe the anisotropy of the GOES behavior law, the orientation distribution function (ODF)-based approach shows interesting features regarding ease of identification and implementation. However, a significant oscillation issue in this model at low magnetic field exists. It is recently reported that a high-order ODF-based method can improve the accuracy of the original model. But the high-order ODF-based model implies an important number of experimental data according to different directions of the applied field to RD (different magnetization angles) to build a model with sufficient accuracy. In addition, the accuracy also depends on how the input magnetization angles are selected between the RD and the transverse direction (TD). In this article, an optimal algorithm for input magnetization angle selection is proposed for the high-order ODF-based method. To validate the proposed algorithm, 13 magnetization angles have been measured. A comparative study has been conducted based on the original and high-order ODF-based models built with the proposed selected magnetization angles. It is shown that the proposed algorithm can reduce the number of experimental data needed for the ODF-based model while providing an acceptable global error.
Oral dispersible films (ODF) are great alternatives to tablet medications as they will simply dissolve in the mouth. There are several ways to produce ODFs, but electrospinning is emerging as one of ...the best methods as it increases the surface to volume ratio which allows it to dissolve easily. ODFs are typically formulated using a combination of polymers to produce the necessary film qualities. The use of κ-carrageenan (κ-CAR), a natural polymer in ODFs are yet to be studied in detail. Therefore, this study aims to develop an ODF from a combination of κ-CAR, polyvinyl alcohol (PVA) and vitamin C, where the latter will act as a model drug carrier. 1.5w/v% κ-CAR and 14w/v% PVA at a ratio of 30:70 was added with different concentrations of vitamin C from 2 to 10w/v%, respectively. The resulting nanofibers were then examined for morphology, water contact angle (WCA) and disintegration time. All the solutions formed uniform nanofibers with an average diameter ranging from 190 to 490 nm and showed hydrophilic properties. Sample 4 showed the fastest disintegration time of 3.68s and the lowest WCA of 38.5°. The results indicated that the best formulation for an ODF was with 8% vitamin C. The findings from this study provide promising groundwork for the use of κ-CAR as the biopolymer in combination with the PVA to develop a biopolymer-based ODF with vitamin C via electrospinning.
We propose an integral concept for tractography to describe crossing and splitting fibre bundles based on the fibre orientation distribution function (ODF) estimated from high angular resolution ...diffusion imaging (HARDI). We show that in order to perform accurate probabilistic tractography, one needs to use a fibre ODF estimation and not the diffusion ODF. We use a new fibre ODF estimation obtained from a sharpening deconvolution transform (SDT) of the diffusion ODF reconstructed from q -ball imaging (QBI). This SDT provides new insight into the relationship between the HARDI signal, the diffusion ODF, and the fibre ODF. We demonstrate that the SDT agrees with classical spherical deconvolution and improves the angular resolution of QBI. Another important contribution of this paper is the development of new deterministic and new probabilistic tractography algorithms using the full multidirectional information obtained through use of the fibre ODF. An extensive comparison study is performed on human brain datasets comparing our new deterministic and probabilistic tracking algorithms in complex fibre crossing regions. Finally, as an application of our new probabilistic tracking, we quantify the reconstruction of transcallosal fibres intersecting with the corona radiata and the superior longitudinal fasciculus in a group of eight subjects. Most current diffusion tensor imaging (DTI)-based methods neglect these fibres, which might lead to incorrect interpretations of brain functions.
Purpose
The orientation distribution function (ODF), which is obtained from the radial integral of the probability density function weighted by rn$$ {r}^n $$ (r$$ r $$ is the radial length), has been ...used to estimate fiber orientations of white matter tissues. Currently, there is no general expression of the ODF that is suitable for any n value in the HARDI methods.
Theory and methods
A novel methodology is proposed to calculate the ODF for any n>−1$$ n>-1 $$ through the Taylor series expansion and a generalized expression for −1<n<4$$ -1<n<4 $$ is provided. Then a series of single‐shell HARDI methods, termed the general orientation transform (GOT), is developed based on the obtained expression. By combining complementary GOTs, a composite estimator is obtained and further optimized via constrained optimization to take full advantage of individual merits. The final optimized HARDI method is termed the combined GOT with constrained optimization (coGOT). The proposed method is compared with other commonly used HARDI methods on the simulated data, the physical phantom data, the ISMRM 2015 Tractography challenge data, and in vivo HCP datasets.
Results
coGOT can resolve crossing fibers with higher resolution, performs better robustness, generates fewer spurious lobes in glyphs, and thus provides distinct improvement in the tractography. The evaluations show coGOT's superior capability in reconstructing the fiber orientations from dMRI signals.
Conclusions
Generalization of the ODF allows us to obtain a wide range of HARDI estimators to select suitable candidates for composite formulation. The optimized estimator coGOT has great potential for studying neural architecture and serving as fiber tracking tools.
A diffusion deconvolution method is proposed to apply deconvolution to the diffusion orientation distribution function (dODF) and calculate the fiber orientation distribution function (fODF), which ...is defined as the orientation distribution of the fiber spin density. The dODF can be obtained from q-space imaging methods such as q-ball imaging (QBI), diffusion spectrum imaging (DSI), and generalized q-sampling imaging (GQI), and thus the method can be applied to various diffusion sampling schemes. A phantom study was conducted to compare the angular resolution of the fODF with the dODF, and the in vivo datasets were acquired using single-shell, two-shell, and grid sampling schemes, which were then reconstructed by QBI, GQI, and DSI, respectively. The phantom study showed that the fODF significantly improved the angular resolution over the dODF at 45- and 60-degree crossing angles. The in vivo study showed consistent fODF regardless of the applied sampling schemes and reconstruction methods, and the ability to resolve crossing fibers was improved in reduced sampling condition. The fiber spin density obtained from deconvolution showed a higher contrast-to-noise ratio than the fractional anisotropy (FA) mapping, and further application on tractography showed that the fiber spin density can be used to determine the termination of fiber tracts. In conclusion, the proposed deconvolution method is generally applicable to different q-space imaging methods. The calculated fODF improves the angular resolution and also provides a quantitative index of fiber spin density to refine fiber tracking.
► The phantom study showed significant improvement in angular resolution. ► The in vivo study showed improvement in angular resolution and fiber tracking. ► The in vivo study showed consistent fODF regardless of the diffusion sampling schemes. ► The fiber spin density showed a higher contrast-to-noise ratio than FA.
Diffusion MRI techniques are used widely to study the characteristics of the human brain connectome in vivo. However, to resolve and characterise white matter (WM) fibres in heterogeneous MRI voxels ...remains a challenging problem typically approached with signal models that rely on prior information and constraints. We have recently introduced a 5D relaxation–diffusion correlation framework wherein multidimensional diffusion encoding strategies are used to acquire data at multiple echo‐times to increase the amount of information encoded into the signal and ease the constraints needed for signal inversion. Nonparametric Monte Carlo inversion of the resulting datasets yields 5D relaxation–diffusion distributions where contributions from different sub‐voxel tissue environments are separated with minimal assumptions on their microscopic properties. Here, we build on the 5D correlation approach to derive fibre‐specific metrics that can be mapped throughout the imaged brain volume. Distribution components ascribed to fibrous tissues are resolved, and subsequently mapped to a dense mesh of overlapping orientation bins to define a smooth orientation distribution function (ODF). Moreover, relaxation and diffusion measures are correlated to each independent ODF coordinate, thereby allowing the estimation of orientation‐specific relaxation rates and diffusivities. The proposed method is tested on a healthy volunteer, where the estimated ODFs were observed to capture major WM tracts, resolve fibre crossings, and, more importantly, inform on the relaxation and diffusion features along with distinct fibre bundles. If combined with fibre‐tracking algorithms, the methodology presented in this work has potential for increasing the depth of characterisation of microstructural properties along individual WM pathways.
Diffusion MRI techniques designed to resolve fibre crossings within a given white matter (WM) voxel typically assume that the voxel‐level microstructural features can be represented by a single signal response function; this precludes the investigation of microscopic differences between the sub‐voxel fibre populations. In this work, we build on a recently introduced 5D relaxation–diffusion correlation MRI framework and present an analysis protocol for deriving and visualising metrics informing on the relaxation rates and diffusivities of distinct fibres. Experiments on a healthy volunteer demonstrate that the presented approach can capture crossings between distinct WM tracts of the human brain and inform on their individual relaxation–diffusion properties.
The texture of deformation and primary recrystallization in copper-nickel alloys with the addition of a small amount of refractory elements such as Nb, Mo, Ta and W was studied. Based on the X-ray ...analysis of the deformation texture using the orientation distribution function, it was shown that the volume fraction of the C and S components in alloys is greater than the double volume fraction of the unfavorable component B. In accordance with this criterion, after primary recrystallization in all the studied alloys, a sharp cubic texture {100}< 001 > was obtained with a volume fraction in the± 10° region of more than 95%. Alloying with refractory elements significantly increases the strength of the base copper-nickel alloy by the mechanism of solid-solution hardening. The evaluation of the mechanical characteristics showed that the increase in the yield stress in the studied alloys is from 25% to 45% with relative to Cu-40% Ni alloy.
•Doping of the Cu-Ni HTSC substrate with a small amount of refractory elements.•Tape substrates were obtained by cold rolling and recrystallization annealing.•Textural analysis of the tapes was carried out using the ODF and EBSD methods.•The ratio of components in rolling texture is a criterion for obtaining sharp cube texture.•Mechanical characteristics of tape substrates made of ternary alloys are analyzed.
PDF
