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1.
Jpn J Radiol ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235674

RESUMEN

PURPOSE: By imaging dopamine transporter (DAT) uptake in the striatum, 123I-FP-CIT SPECT can differentiate dopaminergic neurodegenerative disease (dNDD) and non-dNDD, which differ in pathophysiology and clinical management. Our aim was to compare and validate the diagnostic abilities of various 123I-FP-CIT SPECT quantitative indices for dNDD. MATERIALS AND METHODS: Distribution volume ratio (DVR) and binding ratio (BR), measures of DAT uptake capacity, were measured by analyzing clinical 123I-FP-CIT SPECT images of 29 patients with dNDD, including dementia with Lewy bodies and Parkinson's disease, and 18 patients with non-dNDD, using Montreal Neurological Institute space-based anatomical standardization and an atlas template, which utilizes statistical parametric mapping. Additionally, we computed the specific binding ratio (SBR) based on Bolt's method and the maximum and mean standardized uptake values (SUVmax and SUVmean, respectively). RESULTS: The caudate-to-occipital lobe, putamen-to-occipital lobe, and striatum-to-occipital lobe ratios (COR, POR, and SOR, respectively) on DVR and POR and SOR on BR were significantly lower in dNDD than in non-dNDD, with areas under the ROC curve (AUCs) of 0.941-0.960, showing high diagnostic accuracy for dNDD. However, the AUC of COR on BR was 0.839, indicating lower diagnostic performance. SBR had an AUC of 0.921, while SUVmax and SUVmean had AUCs of 0.906 and 0.900, respectively. Although striatal asymmetry on both DVR and BR exhibited AUCs of 0.728 and 0.734 and asymmetry on SBR showed an AUC of 0.757, the ratio-based DAT quantitative indices were superior. There were strong positive correlations of DVR with BR, DVR with SBR or SUVmax, BR with SBR or SUVmax, and SBR with SUVmax. CONCLUSION: COR, POR, and SOR on DVR and POR and SOR on BR were the most useful DAT quantitative indices. These indices can be compared with SBR and SUV, suggesting that comprehensive evaluation improves the diagnostic accuracy of dNDD.

2.
J Orthop Surg Res ; 19(1): 492, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160555

RESUMEN

OBJECTIVE: As there are no substantial selection criteria for determining the lowest instrumented vertebra (LIV) in adolescent idiopathic scoliosis (AIS) Lenke 5C/6C, thus, many surgeons base their selection on experience. The study aims to compare the selection of the lowest instrumented vertebrae (LIV) lumbar vertebra three (L3) with the use of direct vertebrae rotation (DVR) to the lowest instrumented vertebrae (LIV) lumbar vertebra four (L4) with the use of non-DVR for the correction of adolescent idiopathic scoliosis (AIS) Lenke 5C/6C when the lower end vertebrae (LEV) is at lumbar vertebrae four (L4). METHODS: This prospective study involved 101 patients who were divided into two groups based on different techniques. The patients were prospectively followed up for at least four years. All patients included in the study had a lower end vertebra (LEV) at L4, while patients older than 18 years and patients with prior surgical procedures were excluded. The DVR group consisted of 49 patients, and the non-DVR group included 51 patients. RESULTS: The preoperative mean LIV disc angle was 3.1 ± 3 and 3.1 ± 1, P = 0.097, which corrected to 1.2 ± 0 and 1.1 ± 0 in both groups at 4-year follow-up without statistical significance. The LIVDA and LIVT were statistically insignificant at the preoperative, and there were no significant differences at the follow-up visitation. The DVR group achieved a satisfactory coronal and Cobb's angle correction compared to the NDVR group; however, there were no statistical differences at the follow-up visitations. Both groups achieve a satisfactory correction rate without substantial significance in clinical and radiological outcomes. Furthermore, no post-surgical complications were recorded in either group. CONCLUSIONS: DVR is suitable for selecting L3 as the LIV in AIS Lenke 5C/6C compared to L4 in non-DVR. DVR preserved more segments without substantial complications during the follow-up visitations. Nevertheless, both groups will continue to be followed up to prevent adding-on post-surgical complications.


Asunto(s)
Vértebras Lumbares , Escoliosis , Fusión Vertebral , Humanos , Escoliosis/cirugía , Escoliosis/diagnóstico por imagen , Adolescente , Femenino , Estudios Prospectivos , Masculino , Vértebras Lumbares/cirugía , Vértebras Lumbares/diagnóstico por imagen , Fusión Vertebral/métodos , Rotación , Niño , Estudios de Seguimiento , Resultado del Tratamiento
3.
J Forensic Sci ; 69(1): 117-130, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37817447

RESUMEN

CCTV surveillance systems are ubiquitous IoT appliances. Their forensic examination has proven critical for investigating crimes. DAHUA Technology is a well-known manufacturer of such products. Despite its global market share, research regarding digital forensics of DAHUA Technology CCTV systems is scarce and currently limited to extracting their video footage, overlooking the potential presence of valuable artifacts within their log records. These pieces of evidence remain unexploited by major commercial forensic software, yet they can hide vital information for an investigation. For instance, these log records document user actions, such as formatting the CCTV system's hard drive or disabling camera recording. This information can assist in attributing nefarious actions to specific users and hence can be invaluable for understanding the sequence of events related to incidents. Therefore, in this paper, several DAHUA Technology CCTV systems are thoroughly analyzed for these unexplored pieces of evidence, and their forensic value is presented.

4.
J Forensic Sci ; 68(6): 2002-2011, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37526255

RESUMEN

CCTV surveillance systems are IoT products that can be found almost everywhere. Their digital forensic analysis often plays a key role in solving crimes. However, it is common for these devices to use proprietary file systems, which frequently hinders a complete examination. HIKVISION is a well-known manufacturer of such devices that typically ships its products with its proprietary file system. The HIKVISION file system has been analyzed before but that research has focused on the recovery of video footage. In this paper, the HIKVISION file system is being revisited regarding the log records it stores. More specifically, these log records are thoroughly examined to uncover both their structure and meaning. These unexplored pieces of evidence remain unexploited by major commercial forensic software, yet they can contain critical information for an investigation. To further assist digital forensic examiners with their analysis, a Python utility, namely the Hikvision Log Analyzer, was developed as part of this study that can automate part of the process.

5.
Sensors (Basel) ; 23(16)2023 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-37631683

RESUMEN

Photovoltaic (PV) systems are crucial to the production of electricity for a newly established community in Egypt, especially in grid-tied systems. Power quality (PQ) issues appear as a result of PV connection with the power grid (PG). PQ problems cause the PG to experience faults and harmonics, which affect consumers. A series compensator dynamic voltage restorer (DVR) is the most affordable option for resolving the abovementioned PQ problems. To address PQ difficulties, this paper describes a grid-tied PV combined with a DVR that uses a rotating dq reference frame (dqRF) controller. The main goal of this study is to apply and construct an effective PI controller for a DVR to mitigate PQ problems. The artificial rabbits optimization (ARO) is used to obtain the best tune of the PI controller. The obtained results are compared with five optimization techniques (L-SHADE, CMAES, WOA, PSO, and GWO) to show its impact and effectiveness. Additionally, Lyapunov's function is used to analyze and evaluate the proposed controller stability. Also, a mathematical analysis of the investigated PV, boost converter, and rotating dqRF control is performed. Two fault test scenarios are examined to confirm the efficacy of the suggested control approach. The parameters' (voltage, current, and power) waveforms for the suggested system are improved, and the system is kept running continuously under fault periods, which improves the performance of the system. Moreover, the findings demonstrate that the presented design successfully keeps the voltage at the required level with low THD% values at the load side according to the IEEE standards and displays a clear enhancement in voltage waveforms. The MATLAB/SIMULINK software is used to confirm the proposed system's performance.

6.
Egypt Heart J ; 75(1): 58, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37432517

RESUMEN

BACKGROUND: Aorto-cavitary fistula is a rare complication of infective endocarditis. Multimodal imaging is commonly required to assess the severity and extent of infection because of the complex pathology of the valvular and paravalvular apparatus in endocarditis. CASE PRESENTATION: We present an unusual case of a middle-aged man with recent history of meningoencephalitis who developed infective endocarditis complicated by ruptured abscess in inter-valvular fibrosa between aortic and mitral valve resulting in free communication or fistula formation between aorta and left atrium. Patient underwent double valve replacement (aortic and mitral) along with repair of the aorta. CONCLUSIONS: Our case highlights recognition of this rare clinical presentation of aorto-left atrial fistula in infective endocarditis and the diagnostic role of transesophageal echocardiography in good clinical outcome with aggressive and timely management.

7.
Molecules ; 28(13)2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37446684

RESUMEN

The iconic caged shape of fullerenes gives rise to a series of unique chemical and physical properties; hence a deeper understanding of the attractive and repulsive forces between two buckyballs can bring detrimental information about the structural stability of such complexes, providing significant data applicable for several studies. The potential energy curves for the interaction of multiple van der Waals buckyball complexes with increasing mass were theoretically obtained within the DFT framework at ωB97xD/6-31G(d) compound model. These potential energy curves were employed to estimate the spectroscopic constants and the lifetime of the fullerene complexes with the Discrete Variable Representation and with the Dunham approaches. It was revealed that both methods are compatible in determining the rovibrational structure of the dimers and that they are genuinely stable, i.e., long-lived complexes. To further inquire into the nature of such interaction, Bader's QTAIM approach was applied. QTAIM descriptors indicate that the interactions of these closed-shell systems are dominated by weak van der Waals forces. This non-covalent interaction character was confirmed by the RDG analysis scheme. Indirectly, QTAIM also allowed us to confirm the stability of the non-covalent bonded fullerene dimers. Our lifetime calculations have shown that the studied dimers are stable for more than 1 ps, which increases accordingly with the number of carbon atoms.


Asunto(s)
Fulerenos , Fulerenos/química , Carbono , Análisis Espectral , Fenómenos Físicos
8.
Quant Imaging Med Surg ; 13(6): 3660-3670, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37284094

RESUMEN

Background: The accurate diagnosis of adhesive small bowel obstruction (ASBO) is challenging for surgeons. The aim of this study was to demonstrate that pneumoperitoneum 3-dimensional volume rendering (3DVR) can provide an accurate diagnosis and has applicability in ASBO. Methods: In this retrospective study, patients who underwent preoperative pneumoperitoneum 3DVR and surgery for ASBO between October 2021 and May 2022 were enrolled. The surgical findings were taken as the gold standard, and the kappa test was used to verify the consistency of the pneumoperitoneum 3DVR results and surgical findings. Results: A total of 22 patients with ASBO were included in this study, 27 sites of obstruction adhesions were found during surgery, and 5 patients had both parietal adhesions and interintestinal adhesions. Sixteen parietal adhesions (16/16) were found using pneumoperitoneum 3DVR (κ=1.00; P<0.001), and the diagnosis of parietal adhesions on pneumoperitoneum 3DVR was perfectly consistent with the surgical findings. Eight (8/11) interintestinal adhesions were found using pneumoperitoneum 3DVR (κ=0.727; P<0.001), and the diagnosis of interintestinal adhesions on pneumoperitoneum 3DVR was substantially consistent with the surgical findings. Conclusions: The novel pneumoperitoneum 3DVR is accurate and applicable in ASBO. It can help personalize the treatment of patients and can be useful in planning a more effective surgical approach.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 296: 122660, 2023 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-37043918

RESUMEN

Splitting of the ground state and some excited symmetric bending vibrational states due to inversion tunneling of the oxygen atom in the H3O+, H3O- ions and in the H3O radical are analyzed by numerically solving the vibrational Schrödinger equation of restricted (2D) dimensionality. As two vibrational coordinates, we used 1) the distance of the oxygen atom from the plane of a regular triangle formed by three hydrogen atoms and 2) a symmetry coordinate composed of three distances between chemically non-bonded hydrogen atoms. The kinetic energy operator in this case takes the simplest form. The 2D potential energy surface (PES) in the given coordinates was calculated for H3O+ at the CCSD(T)/aug-cc-pVTZ and CCSD(T)-F12/cc-pVTZ-F12 levels of theory. The same 2D PES for the H3O- anion and H3O radical were calculated at the CCSD(T)/aug-cc-pVQZ, CCSD(T)/d-aug-cc-pVQZ and UCCSD(T)/aug-cc-pVQZ, UCCSD(T)/d-aug-cc-pVQZ levels of theory, respectively. The tunneling splittings were calculated for the cations H316O+, D316O+, T316O+, H318O+, D318O+, T318O+. The tunneling splittings for the H3O-, D3O-, T3O- anions and H3O, D3O, T3O radicals were calculated for the first time. The results of calculations demonstrate good agreement with experimental values of the tunneling splittings in the ground state and in some excited vibrational states of the H316O+ and D316O+ cations.

10.
Front Neurol ; 14: 1045644, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36846134

RESUMEN

Introduction: Synapse loss is one of the hallmarks of Alzheimer's disease (AD) and is associated with cognitive decline. In this study, we tested [18F]SDM-16, a novel metabolically stable SV2A PET imaging probe, in the transgenic APPswe/PS1dE9 (APP/PS1) mouse model of AD and age-matched wild-type (WT) mice at 12 months of age. Methods: Based on previous preclinical PET imaging studies using [11C]UCB-J and [18F]SynVesT-1 in the same strain animals, we used the simplified reference tissue model (SRTM), with brain stem as the pseudo reference region to calculate distribution volume ratios (DVRs). Results: To simplify and streamline the quantitative analysis, we compared the standardized uptake value ratios (SUVRs) from different imaging windows to DVRs and found that the averaged SUVRs from 60-90 min post-injection (p.i.) are most consistent with the DVRs. Thus, we used averaged SUVRs from 60-90 min for group comparisons and found statistically significant differences in the tracer uptake in different brain regions, e.g., hippocampus (p = 0.001), striatum (p = 0.002), thalamus (p = 0.003), and cingulate cortex (p = 0.0003). Conclusions: In conclusion, [18F]SDM-16 was used to detect decreased SV2A levels in the brain of APP/PS1 AD mouse model at one year old. Our data suggest that [18F]SDM-16 has similar statistical power in detecting the synapse loss in APP/PS1 mice as [11C]UCB-J and [18F]SynVesT-1, albeit later imaging window (60-90 min p.i.) is needed when SUVR is used as a surrogate for DVR for [18F]SDM-16 due to its slower brain kinetics.

11.
J Nucl Med ; 64(2): 281-286, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36265910

RESUMEN

Semiquantitative PET measures such as SUV ratio (SUVr) have several advantages over quantitative measures, such as practical applicability and relative computational simplicity. However, SUVr may potentially be affected by changes in blood flow, whereas quantitative measures such as nondisplaceable binding potential (BPND) are not. For 18F-flortaucipir PET, the sensitivity of SUVr for changes in blood flow is currently unknown. Therefore, we compared semiquantitative (SUVr) and quantitative (BPND) parameters of longitudinal 18F-flortaucipir PET scans and assessed their vulnerability to changes in blood flow. Methods: Subjects with subjective cognitive decline (n = 38) and Alzheimer disease patients (n = 24) underwent baseline and 2-y follow-up dynamic 18F-flortaucipir PET scans. BPND and relative tracer delivery were estimated using receptor parametric mapping, and SUVr at 80-100 min was calculated. Regional SUVrs were compared with corresponding distribution volume ratio (BPND + 1) using paired t tests. Additionally, simulations were performed to model effects of larger flow changes in different binding categories. Results: Results in subjective cognitive decline and Alzheimer disease showed only minor differences between SUVr and BPND changes over time. Relative tracer delivery changes were small in all groups. Simulations illustrated a variable bias for SUVr depending on the amount of binding. Conclusion: SUVr provided an accurate estimate of changes in specific binding for 18F-flortaucipir over a 2-y follow-up during which changes in flow were small. Notwithstanding, simulations showed that large(r) flow changes may affect 18F-flortaucipir SUVr. Given that it is currently unknown to what order of magnitude pharmacotherapeutic interventions may induce changes in cerebral blood flow, caution may be warranted when changes in flow are potentially large(r), as in clinical trials.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Carbolinas , Disfunción Cognitiva/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Circulación Cerebrovascular , Proteínas tau/metabolismo
12.
Mol Imaging Biol ; 24(3): 404-415, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34622422

RESUMEN

PURPOSE: To identify a reliable alternative to the full blood [11C]PBR28 quantification method that would be easily replicated in multiple research and clinical settings. PROCEDURES: Ten [11C]PBR28 scans were acquired from 7 healthy non-human primates (NHP). Arterial input functions (AIFs) were averaged to create a population template input function (TIF). Population-based input functions were created by scaling the TIF with injected activity per body weight (PBIF) or unmetabolized tracer activity in blood at 15-,30-, and 60-min post-injection (PBIF15, PBIF30, and PBIF60). Two additional input functions were used: the native unmetabolized total plasma activity (Totals) and the Totals curve metabolite corrected by a scaled template parent fraction from a 30-min sample (TPF30-IF). Total distribution volumes (VTs) were calculated using PBIF, PBIF30, PBIF15, PBIF60, Totals, TPF30-IF, and the individual AIF (VTAIF). Distribution volume ratios (DVR) were computed using the cerebellum and the centrum semiovale (CSO), as pseudo-reference regions (DVRCereb, DVRCSO). Results obtained with each method were compared to VTAIF. Applicability of these alternative methods was tested on an independent pharmacological challenge dataset of microglial activation and depletion. Evaluation was carried at baseline, immediately after intervention (acute), and weeks post-intervention (post-recovery). RESULTS: VTs computed using PBIF15 and PBIF30 showed the best correlation to VTAIF (r > 0.90), while VT derived from the blood-free-scaled PBIF showed poor correlation (r = 0.46) and DVRCSO correlated the least (r = 0.26). In the pharmacological challenge study, most population-derived VT values were comparable to VTAIF at baseline and showed varied sensitivity to challenges at acute and post-recovery evaluation. DVR values did not detect relevant changes. CONCLUSIONS: Population-based input functions scaled with a single blood sample might be a useful alternative to using AIF to compute [11C]PBR28 binding in healthy NHPs or animals with comparable metabolism and overall perform better than pseudo-reference regions approaches.


Asunto(s)
Encéfalo , Tomografía de Emisión de Positrones , Animales , Arterias/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Tomografía de Emisión de Positrones/métodos , Primates
13.
ISA Trans ; 121: 316-326, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33888296

RESUMEN

With the advancement of technology, electric equipment and loads have become more sensitive to problems related to power quality, such as voltage sag, swell, imbalances, and harmonics. To detect faults and to protect sensitive loads from these voltage distortions, a Dynamic Voltage Restorer (DVR) series compensator is among the best available cost-effective solutions. One of the main goals of the DVR is to achieve a control structure that is robust, stable, and can handle properly the disturbances (e.g., grid voltage issues, load current, and fluctuations at the DC link voltage) and model uncertainties (e.g., inverters and filter parameters). In this work, a novel framework control strategy based on Uncertainty and Disturbance Estimator (UDE) is proposed to improve the response of the DVR to properly compensate the load voltage under a variety of power quality issues, particularly the ones associated with the grid voltage disturbances. Additionally, the stability of the proposed control system is analyzed and validated using the Lyapunov stability theory. The advantages of the new control system are robustness, simplified design, good harmonic rejection, low tracking error, fast response, and sinusoidal reference tracking without the need for voltage transformations or specific frequency tuning (e.g., abc-dq0 and Proportional-Resonant). This research uses the MATLAB/Simulink software to validate the effectiveness of the proposed scheme under a diverse set of conditions with no control limitations. Moreover, the designed controller is tested under real conditions using Hardware-In-the-Loop (HIL) validation with OPAL-RT real-time simulator coupled with a TI Launchpad microcontroller. The results demonstrate a good performance of the proposed control strategy for a quick transient response and a great harmonic rejection when subject to grid voltage distortions.

14.
DNA Cell Biol ; 40(10): 1338-1348, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34529517

RESUMEN

Ficolins are pattern recognition molecules that are involved in innate immune defense. Ficonin-2 (FCN2) has a specific affinity for lipoteichoic acid present in the cell wall of Streptococcus pyogenes, an etiological agent for rheumatic heart disease (RHD). We have estimated FCN2 serum levels and analyzed the functional variants of FCN2 in 400 RHD patients, 617 healthy controls, and 581 individuals belonged to various ethnic populations, who are inhabited in various geographical regions of India. Our study revealed that the FCN2 -986A and +6359T alleles were the risk factors for RHD susceptibility (p = 0.0007 for -986G>A; p = 0.0004 for +6359C>T). The haplotype AGGT (p = 0.0024) was observed to be a risk factor for RHD susceptibility, and the haplotype GGAC (p = 0.002) was found to confer protection against RHD. The level of serum FCN2 was significantly higher in controls (p < 0.0001) and in controls with GGAC haplotypes (p < 0.0001). The frequency of the risk alleles -986A and +6359T was found to be more prevalent in Northern and North-Western (Indo-European) India. The protective GGAC haplotype was found more prevalent in Eastern (Tibeto-Burman) and South-Western (Dravidian) India. Alleles -986A and +6359T were in positive correlation with the prevalence of RHD (regression coefficient = 1.84 and 1.94, respectively), whereas GGAC haplotype was in negative correlation with prevalence of RHD (regression coefficient = -1.71). In conclusion, we found that low level of serum ficolin-2 is significantly associated with RHD. Further, FCN2 -986A and +6359T alleles and AGGT haplotype are associated with increased susceptibility to RHD, while GGAC haplotype is associated with moderate protection against RHD.


Asunto(s)
Lectinas/genética , Polimorfismo de Nucleótido Simple , Cardiopatía Reumática/genética , Adulto , Anciano , Femenino , Haplotipos , Humanos , India , Masculino , Persona de Mediana Edad , Ficolinas
15.
Front Plant Sci ; 12: 699308, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34456941

RESUMEN

Leaves are the main organ for photosynthesis, and variations in leaf color affect photosynthesis and plant biomass formation. We created two similar whole-plant pale green mutants (pem1 and pem2) from the double haploid (DH) Chinese cabbage line "FT" through ethyl methanesulfonate (EMS) mutagenesis of seeds. Photosynthetic pigment contents and net photosynthetic rates were significantly lower in the mutants than in the wild-type "FT," and the chloroplast thylakoid endomembrane system was poor. Genetic analysis showed that the mutated phenotypes of pem1 and pem2 were caused by a single nuclear gene. Allelism tests showed that pem1 and pem2 were alleles. We mapped Brpem1 to a 64.25 kb region on chromosome A10, using BSR-Seq and map-based cloning of 979 F2 recessive individuals. Whole-genome re-sequencing revealed a single nucleotide polymorphism (SNP) transition from guanine to adenosine on BraA10g021490.3C in pem1, causing an amino acid shift from glycine to glutamic acid (G to E); in addition, BraA10g021490.3C in pem2 was found to have a single nucleotide substitution from guanine to adenosine, causing an amino acid change from E to lysine (K). BraA10g021490.3C is a homolog of the Arabidopsisdivinyl chlorophyllide a 8-vinyl-reductase (DVR) gene that encodes 3,8-divinyl protochlorophyllide a 8-vinyl reductase, which is a key enzyme in chlorophyll biosynthesis. Enzyme activity assay and chlorophyll composition analysis demonstrated that impaired DVR had partial loss of function. These results provide a basis to understand chlorophyll metabolism and explore the mechanism of a pale green phenotype in Chinese cabbage.

16.
Anat Histol Embryol ; 50(1): 108-113, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32808343

RESUMEN

The objective of the current study was to describe the structures of the pastern and coffin joints in dromedary camel using x-ray, bone and soft tissue windows computed tomography (CT) and three-dimensional volume rendering (3DVR) of CT imaging. 3DVR of CT was obtained at the slight flexed dorsal view, plantar view, dorsolateral view and lateral view which explained all the surfaces and structures of the digit bony parts even the parts of the articular surface. The processed images of 3DVR of CT showed different patterns of the cortical, cancellous, subchondral bones and medullary cavity of the bones of the digits. The present study showed clearly all the hard and soft tissues in the pastern and coffin joints of the camel in CT images; however, the plantar ligaments of the pastern joint and ligaments of the navicular cartilage identified on CT images. The CT soft tissue window visualized the joint cavity and their pouches and tendon sheath of the flexor tendons better than the bone window CT. The radiographic, CT and 3D images could be used as a normal reference for the interpretation of some clinical diseases in the pastern and coffin joints of the camel.


Asunto(s)
Camelus/anatomía & histología , Pie/anatomía & histología , Pie/diagnóstico por imagen , Articulaciones/anatomía & histología , Articulaciones/diagnóstico por imagen , Tomografía Computarizada por Rayos X/veterinaria , Animales , Cadáver , Medios de Contraste , Femenino , Imagenología Tridimensional , Masculino
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 243: 118707, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32827906

RESUMEN

The capability of Diffusion Quantum Monte Carlo (DMC) to produce high quality potential energy curve (PEC) was evaluated. H2+, HeH+ and LiH PECs were built by all-electron fixed-node DMC calculations. Trial wave functions were obtained from Hartree-Fock (HF) (H2+), MCSCF and CI (HeH+ and LiH) calculations multiplied by Jastrow factor. The quality of these generated PECs was analyzed throughout equilibrium distance, dissociation energy, vibrational energies and rovibrational spectroscopic constants (ωe, ωexe, ωeye, αe, γe and Be). The Discrete Variable Representation (DVR) and the Dunham approaches were used to determine the rovibrational spectroscopic constants. The PECs and the aforementioned properties were also obtained by the following methods: MCSCF/aug-cc-pV5Z (LiH), CCSD(T)/aug-cc-pV5Z (HeH+ and LiH) and HF (H2+ and HeH+) levels. The results of these DMC computations, specially the DMC-DVR procedure, are the most accurate among others DMC calculations available in the literature for these systems. They suggest that DMC can be used to achieve accurate PECs to produce spectroscopic properties with the same level of accuracy of theoretical benchmarks and experimental data of the literature.

18.
Cureus ; 12(2): e7085, 2020 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-32226686

RESUMEN

Introduction Poor knowledge retention is one reason for medical student attrition in learning and has been a huge concern in medical education. Three-dimensional virtual reality (3D-VR)-based teaching and learning in medical education has been promoted to improve student learning outcomes. This study aimed to determine the effectiveness of 3D-VR in knowledge retention in human anatomy courses as compared to traditional teaching methods among medical students. Methods A convergent mixed methods design was utilized to evaluate learning outcomes in terms of short- and long-term knowledge retention scores among students using 3D-VR and those using traditional models and to describe students' experiences and views of the use of 3D-VR as a teaching and learning tool. Results Male students who used the 3D-VR tool had significantly higher short- and long-term knowledge scores than males who used the traditional methods. Meanwhile, females who used traditional methods showed significantly higher short-term knowledge scores than females who used 3D-VR. Conclusion Medical students described 3D-VR as a learning tool with a great deal to offer for learning human anatomy as compared to traditional methods. Therefore, we recommend adding the use of 3D-VR in the anatomy curriculum. However, several 3D-VR limitations were also identified, which may hinder its utilization for teaching and learning. These concerns must be addressed before 3D-VR tools are considered for implementation in medical education human anatomy courses.

19.
J Forensic Sci ; 65(4): 1155-1168, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32134510

RESUMEN

As the closed-circuit television (CCTV) security industry transitioned from analog media to digital video recorders (DVRs) with digital storage, the law enforcement community struggled with the means with which to collect the recordings. New guidelines needed to be established to determine the collection method which would be efficient as well as provide the best quality evidence from live DVRs. A test design was developed to measure, quantify, and rank the quality of acquisition methods used on live systems from DVRs typically used in digital CCTV systems. The purpose was to determine guidelines for acquiring the best quality video for investigative purposes. A test pattern which provided multiple quantifiable metrics for comparison between the methods of acquisition was used. The methods of acquisition included direct data download of the proprietary file and open file format as well as recording the video playback from the DVR via the available display monitor connections including the composite video, Video Graphics Array (VGA), and high-definition multimedia interface (HDMI). While some acquisition methods may provide the best quality evidence, other methods of acquisition are not to be discounted depending on the situation and need for efficiency. As an investigator that needs to retrieve video evidence from live digital CCTV systems, the proprietary file format, overall, provides the best quality evidence. However, depending on the circumstance and as recording technology continues to evolve, options other than the proprietary file format may provide quality that is equal to or greater than the proprietary file format.

20.
J Comp Neurol ; 528(2): 321-359, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31407337

RESUMEN

Recent reports have shown that the avian visual dorsal ventricular ridge (DVR) is organized as a trilayered complex, in which the forming layers-the thalamo-recipient entopallium (E), an overlaying nidopallial stripe called intermediate nidopallium (NI), and the dorsally adjacent mesopallium ventrale-appear to be extensively interconnected by topographically organized columns of reciprocal axonal processes running perpendicular to the layers, an arrangement highly reminiscent to that of the sensory cortices of mammals. In the present report, we implemented in vivo anterograde and retrograde tracing techniques aiming to elucidate the organization of the connections of this complex with other pallial areas. Previous studies have shown that the efferent projections of the visual DVR originate mainly from the NI and E, reaching several distinct associative and premotor nidopallial areas. We found that the efferents from the visual DVR originated solely from the NI, and confirmed that the targets of these projections were the pallial areas described by previous studies. We also found novel projections from the NI to the visual hyperpallium, and to the lateral striatum. Moreover, we found that these projections were reciprocal, topographically organized, and originated from different cell populations within the NI. We conclude that the NI constitutes a specialized layer of the visual DVR that form the core of a dense network of highly specific connections between this region and other higher order areas of the avian pallium. Finally, we discuss to what extent these hodological properties resemble those of the mammalian cortical layers II/III.


Asunto(s)
Columbidae/anatomía & histología , Vías Nerviosas/citología , Telencéfalo/citología , Animales , Femenino , Masculino
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