Mean Acquisition Research Articles

Deep learning reconstruction of diffusion-weighted brain MRI for evaluation of patients with acute neurologic symptoms

Purpose: We aimed to evaluate whether the deep-learning (DL) accelerated diffusion weighted image (DWI) is clinically feasible for evaluating patients with acute neurologic symptoms, regarding its shorter study time and acceptable image quality. Materials and methods: In this retrospective study, brain images obtained at DWI with a b-value of 0 s/mm2 and DWI with a b-value of 1000 s/mm2 (DWI 1000) from 321 consecutive patients with acute stroke-like symptom were reconstructed with and without DL algorithm. We compare the diagnostic performance between DL-DWI and conventional DWI for detecting brain lesions, including acute infarction. We assessed the diagnostic accuracy of conventional DWI and DL-DWI and compared the results. Qualitative analysis based on image quality was assessed and compared using a five-point visual scoring system. Apparent diffusion coefficients (ADCs) from DWI with and without DL were also compared. Results: The mean acquisition time for the DL-DWI (49 s) was significantly shorter (P < 0.001) than conventional DWI (165 s). Both DWI with and without DL showed similar performance in diagnosing brain lesions especially sensitivity (98.8% in both DWI and DL-DWI) and specificity (99.5% in both DWI and DL-DWI). Overall image quality, gray-white matter and deep gray matter differentiation of two sequences were similar. DL DWI showed more artifacts than DWI. Lesion conspicuity, especially smaller than 5 mm, was better with DL DWI than conventional DWI (p = 0.03). ADC values of white matter, deep gray matter, and pons with DL were lower than conventional DWI. Conclusions: Compared to conventional DWI, DL-DWI achieved comparable image quality and brain lesion visualization for acute neurological symptoms, with a significantly shorter scan time.

Early acquisition of figurative meanings in polysemous nouns and verbs

Early acquisition of figurative meanings in polysemous nouns and verbs

DINIY BARQAROR BIRIKMALARNING STILISTIK XUSUSIYATLARI

In this article, the stylistic characteristics of stable religious compounds, their acquisition of different meanings in different situations, and their appearance in the form of anaphora, epithet, phrase, alliteration, antithesis in them are revealed with the help of vivid examples.

Using syntax and semantics to acquire subjective adjective meanings

ABSTRACT Adjectives like good, nice, pretty, and big are among the most frequent adjectives heard by children in the ambient language, and among the first adjectives produced by children. While these gradable adjectives are ostensibly short and sweet, their abstract semantic representations encode reference to features of the discourse context, including speaker subjectivity, which are surprisingly complex, and which also give rise to specific subclasses. How, then, do children acquire these fine-grained adjectival meanings? In this research, we hypothesize that as with verbs, the linguistic environments in which these adjectives appear provide surface-level distributional cues that narrow the space of meaning. In a proof-of-concept experiment with adults following in the footsteps of the Human Simulation Paradigm, we provide empirical evidence that surface-level linguistic patterns support the acquisition of different subclasses of subjective adjectives. Adults were presented with scripted dialogues featuring novel words in controlled linguistic environments manipulating grammatical subjects, adverbial modifiers, standard phrases, syntactic complements, and evidence of faultless disagreement among speakers. Participants were then asked to guess the word meaning (either incrementally after each ‘frame’ or after multiple frames) and rate their confidence. Results, as measured by the percentage of category-consistent, frame-compliant guesses, paired with an increase in confidence levels, indicate a sensitivity to this surface-level information, thereby highlighting the role of the linguistic environment in supporting the acquisition of adjective meaning.

Dual drivers of bilingual semantic accent: Semantic relations and input limitations

Research question: Second language (L2) learners may have a “semantic accent,” using L2 words differently from a native speaker. The current studies investigate how learning conditions and the need to use different semantic dimensions may constrain the acquisition of L2 meanings. Approach: In Experiment 1, we asked whether first language (L1) Mandarin speakers would successfully learn English carry and hold with intensive input in a laboratory training procedure. In Experiment 2, we asked whether the difficulties observed were due to differing semantic dimensions per se or to the need to move from a larger number of fine-grained native distinctions to a smaller number of broader English meanings. Data and analysis: Word definitions and label choice after training were scored for consistency with native performance. Conclusions: Experiment 1 supported the idea that intensive input helps, but Experiment 2 suggested that any kind of semantic difference from L1 is challenging even with intensive input. Originality: The current study clarifies the contributions of learning conditions and L1-L2 semantic differences in semantic accent. Implications: Reducing semantic accent may require instruction in specific L1-L2 differences and cultivation of metacognitive sensitivity to the potential for differences.

Optimization of acquisition patterns for establishing inter CubeSat optical communications

As commercially available CubeSats with up to six standardized units cannot achieve the precision required for an instantaneous establishment of a low-divergence optical inter-satellite link, search patterns are used to scan the remaining field of uncertainty. This analysis optimizes the simultaneously executed search pattern combinations of the two laser communication terminals involved. Based on a Monte Carlo simulation, the perturbations on these links are investigated, and the corresponding key performance parameters such as mean acquisition time and success rate are calculated. The results are penalized by the hardware specifications, including actuator and sensor bandwidths, given by their design. Residual attitude error components imply a significant influence on the acquisition process and are therefore presented within this work. The pattern pairs are fed through an automated optimization algorithm to tune and analyze them. In this particular scenario of two CubeISL models, the mean duration for a first detected acquisition hit is within a pattern period of 3.2 s for the best performing pairs spiral-rose and lissajous-rose. Assuming an uncertainty field of ±0.2deg due to limited attitude knowledge, success rates between 82.3% and 99.9% are achieved.

Understanding Nosocomial Amplification by Identifying Important Parameters in a Community-Hospital Model

Background: The phenomena of emerging infectious diseases accelerating once they reach healthcare facilities have been well documented. Outbreaks of MERS-CoV, SARS-CoV, and COVID-19 have led to in-hospital transmission where the initial patient infects healthcare workers, patients, visitors, etc., with infection control policies unable to curtail the spread early on. We refer to this phenomenon as nosocomial amplification. Nosocomial amplification causes an undue burden on a hospital that’s already strained from the pandemic. We aimed to understand which hospital-level parameters impact the community most and vice versa. Methods: We adapted an SEIR compartmental model to have two interconnected units, a community unit and a hospital special care unit, to determine the number of COVID-19 acquisitions in each of them over a hypothetical year. The model was stochastically simulated using Gillespie’s Direct Method for 1000 iterations. A parameter sensitivity analysis assessed the effects each parameter had on the model. The original values of all parameters were allowed to vary +/- 50%. The number of simulation acquisitions was normalized as a percent change from the original model’s mean acquisition. Results: Our analysis found that parameters impacting the community had a disproportionate impact on COVID-19 acquisitions in the hospital as compared to the special care unit, as did the parameters governing the level of asymptomatic transmission. Transmission between healthcare workers facilitated within-hospital transmission even when strict patient-based cohorting and testing were in place. Extensive community-level transmission was also found to readily overwhelm hospital-level infection control at realistic levels of effectiveness and compliance. Conclusion: These findings illustrate that hospitals and the community are tightly linked systems. Hospitals may reintroduce infection into the community that might have contained or mitigated ongoing outbreaks or introduce the disease into a disease-free population; community transmission puts tremendous pressure on infection control. In the future, we can model policies to curb an existing COVID-19 outbreak or subsequent outbreaks to avoid or minimize nosocomial amplification, thus improving the disproportionate burdens on the healthcare system.

Accelerated cardiac cine magnetic resonance imaging using deep low-rank plus sparse network: validation in patients.

Accurate and reproducible assessment of left ventricular (LV) volumes is important in managing various cardiac conditions. However, patients are required to hold their breath multiple times during data acquisition, which may result in discomfort and restrict cardiac motion, potentially compromising the accuracy of the detected results. Accelerated imaging techniques can help reduce the number of breath holds needed, potentially improving patient comfort and the reliability of the LV assessment. This study aimed to prospectively evaluate the feasibility and accuracy of LV assessment with a model-based low-rank plus sparse network (L+S-Net) for accelerated magnetic resonance (MR) cine imaging. Fourty-one patients with different cardiac conditions were recruited in this study. Both accelerated MR cine imaging with L+S-Net and traditional electrocardiogram (ECG)-gated segmented cine were performed for each patient. Subjective image quality (IQ) score and quantitative LV volume function parameters were measured and compared between L+S-Net and traditional standards. The IQ score and LV volume measurements of cardiovascular magnetic resonance (CMR) images reconstructed by L+S-Net and standard cine were compared by paired t-test. The acquisition time of the two methods was also calculated. In a quantitative analysis, L+S-Net and standard cine yielded similar measurements for all parameters of LV function (ejection fraction: 35±22 for standard vs. 33±23 for L+S-Net), although L+S-Net had slightly lower IQ scores than standard cine CMR (4.2±0.5 for L+S-Net vs. 4.8±0.4 for standard cine; P<0.001). The mean acquisition time of L+S-Net and standard cine was 0.83±0.08 vs. 6.35±0.78 s per slice (P<0.001). Assessment of LV function with L+S-Net at 3.0 T yields comparable results to the reference standard, albeit with a reduced acquisition time. This feature enhances the clinical applicability of the L+S-Net approach, helping alleviate patient discomfort and motion artifacts that may arise due to prolonged acquisition time.

Cardiovascular magnetic resonance 3D LGE imaging for atrial fibrillation ablation

Abstract Objective To assess feasibility and reliability of cardiac magnetic resonance (CMR) imaging in visualizing left atrial (LA) structural changes that patients with paroxysmal atrial fibrillation (PAF) undergo acutely and long-term post ablation. Two different ablation methods i.e pulsed filed ablation (PFA) and cryoablation were studied. Background Pulmonary vein (PV) isolation has become the cornerstone technique for catheter ablation in patients with drug-refractory atrial fibrillation (AF). At present, almost all ablation technologies are mediated by a thermal effect. Recently, pulsed field ablation (PFA) has been introduced as a new energy source. PFA is a non-thermal ablative modality in which high voltage ultra-short pulses are applied to target tissue, while preserving the extracellular matrix architecture, nerves, and microvascular structures. Few data exist showing different structural LA changes between the two methods using Three-Dimensional (3D) Late Gadolinium Enhancement (LGE) Imaging. Methods CMR imaging was performed pre-ablation, acutely (&amp;lt;24 h), and 3 months post-ablation in 10 patients with paroxysmal atrial fibrillation (AF) undergoing pulmonary vein (PV) isolation with PFA (n = 5) or cryoablation (n = 5). 3D LGE and T2-weighted images were analysed. We obtained two data sets of 3D whole heart LGE imaging with high resolution, 20minutes post gadolinium injection. Patients underwent two acquisitions: the conventional respiratory navigated, electrocardiographically-gated 3D fast gradient echo (1.3slice thickness, 256x256 matrix acquisition) and the image-navigated isotropic high resolution 3D LGE with Dixon water-fat separation. 3D LGE data were analysed using a dedicated (ADAS LA) software in order to produce a 3D-LA model visualization of LGE areas. Results In the acute stage, LGE volume was 50% larger after PFA vs. cryoablation (P &amp;lt; 0.001), and oedema on T2 imaging was significantly smaller (visual estimation) on PFA cases. LGE rings surrounding PV ostia were more homogeneous after PFA, with no sign of microvascular damage or intramural hemorrhage as compared to cryoablation cases. In the chronic stage, the majority of acute LGE had disappeared after PFA, whereas most LGE persisted after cryo-ablation. The two 3D LGE sequences used for analysis showed complete agreement in the visualization of atrial scar with superior image quality of the novel sequence. The mean acquisition time for 3D LGE imaging was 11±4minutes for the conventional fast gradient echo sequence, and 5±2minutes for the novel 3D self-image navigated LGE sequence. Conclusions CMR imaging may help in visualization and understanding of LA structural remodeling post different ablation techniques.

Cardiac magnetic resonance - aided ventricular tachycardia substrate ablation

Abstract Objectives To assess feasibility and reliability of Cardiac magnetic resonance (CMR)-derived pixel signal intensity (PSI) maps obtained by Three Dimensional (3D)- Late Gadolinium Enhancement (LGE) images for detecting potential targets for VT substrate ablation procedures. Background Parametric imaging with color-coded PSI maps obtained from pre-ablation 3D LGE -CMR imaging can be used for identification and characterization of arrhythmic abnormal substrate. Recent publications have shown that PSI maps permit visualization of border zone areas inside the scar. Specifically, corridors of viable tissue within the scar connecting healthy myocardium define VT corridors that may be the electrical equivalent of the abnormal conducting channels on the electroanatomical mapping (EAM). Methods 8 patients with scar-dependent monomorphic VTs who underwent 3D-LGE CMR imaging prior to substrate ablation were included in the study. The studies were performed at 1.5T scanner. We obtained two data sets of 3D whole heart LGE imaging with high resolution. Patients underwent two acquisitions: the conventional respiratory navigated, electrocardiographically-gated 3D fast gradient echo (1.3slice thickness, 256x256 matrix acquisition) and the image-navigated isotropic high resolution 3D GE with Dixon water-fat separation. 3D LGE-CMR images were processed with ADAS-VT software to produce a 3-dimensional model of the heart with 10 layers from the endocardium to epicardium and PSI maps color-coded from the LGE data projected to each of the shells (Figure 1). In the LGE-CMR PSI maps, VT corridors were obtained automatically by the ADAS VT software. Subsequently, data were given to the electrophysiologists and merged with the CARTO3 system EAM data obtained for the ablation (Figure2). CMR information was used to facilitate the identification of target ablation sites in the areas identified by CMR as abnormal substrate and radiofrequency was applied in the presence of both a pathological electrogram (EGM) and a VT corridor as identified by CMR. Results There was a 95% agreement between the abnormal conducting channels as detected by abnormal electrograms in the EAM and the VT corridors identified by 3D LGE CMR imaging. In two occasions, there was one VT corridor that did not correlate with abnormal electrograms and was not ablated. The two 3D LGE sequences used for ADAS-VT corridors analysis showed complete agreement in the number and location of VT corridors. Mean acquisition time for 3D LGE imaging was 11±4minutes for the conventional fast gradient echo sequence, and 5±2minutes for the novel 3D self-image navigated LGE sequence. The image quality of 3D LGE was superior with the Dixon fat-water separation. Overall CMR-aided VT ablation reduced the procedural and fluoroscopy time by 40%. Conclusions CMR-aided VT ablation is feasible, reliable and significantly reduces the procedural time.

Signal design and performance analysis for LEO high dynamic navigation application

Abstract With the development of GNSS (Global Navigation Satellite System), LEO (Low Earth Orbit) systems are adopted to enhance the system performance of GNSS. The signal Doppler of the LEO satellite is seven to nine times that of GNSS signals, which benefits positioning performance but leads to high acquisition complexity. This paper proposes the combination of a CSS (Chirp Spread Spectrum) marker and the main body of traditional modulation methods for high dynamic application. The acquisition calculation complexity and mean acquisition time of the proposed signal are analysed and compared with the traditional signal. The result shows that the acquisition calculation complexity is just 26 % of the traditional signal under the parameters considered and the mean acquisition time of the proposed signal is also lower than the traditional signal. Hence, the proposed signal is able to decrease the mean acquisition time of the receiver under the constraint of calculation complexity and should be adopted for LEO high dynamic application.

How well are primary and secondary meanings of L2 words acquired?

Abstract Most words in a language have more than one meaning. Yet, few studies have explicitly examined the acquisition of secondary meanings of L2 words and the extent to which polysemy and homonymy affect vocabulary learning. This study explores the effect of polysemy and homonymy on the deliberate acquisition of the form–meaning connections of L2 words. Thirty-six EFL learners (compared with a control group of 30) learned secondary polysemous and homonymous meanings of familiar words and primary meanings of unfamiliar words using flashcards. Knowledge of target words was measured using meaning–recall and meaning–recognition tests immediately after the treatment and again one week later. The findings indicated that learning another meaning for a familiar word was just as difficult as learning the primary meaning of an unfamiliar word, suggesting that the type of meaning (primary, secondary polysemous, or secondary homonymous) might not be an influencing factor in the deliberate acquisition of L2 words.

The role of emotion in acquisition of verb meaning

ABSTRACT Children’s earliest acquired words are often learned through sensorimotor experience, but it is less clear how children learn the meaning of concepts whose referents are less associated with sensorimotor experience. The Affective Embodiment Account postulates that children use emotional experience to learn more abstract word meanings. There is mixed evidence for this account; analyses using mega-study datasets suggest that negative or positively valenced abstract words are learned earlier than emotionally neutral abstract words, yet the relationship between sensorimotor experience and valence is inconsistent across different methods of operationalising sensorimotor experience. In the present study, we tested the Affective Embodiment Account specifically in the context of verb acquisition. We tested two semantic dimensions of sensorimotor experience: concreteness and embodiment ratings. Our analyses showed that more positive and negative abstract verbs are acquired at an earlier age than neutral abstract verbs, consistent with the Affective Embodiment Account. When sensorimotor experience is operationalised as embodiment, high embodiment verbs are acquired at an earlier age than low embodiment verbs, and there is further benefit for high embodiment and positively valenced verbs. The findings further clarify the role of Affective Embodiment as a mechanism of language acquisition.

Deep-learning-based reconstruction of T2-weighted magnetic resonance imaging of the prostate accelerated by compressed sensing provides improved image quality at half the acquisition time.

Deep-learning-based reconstruction (DLR) improves the quality of magnetic resonance (MR) images which allows faster acquisitions. The aim of this study was to compare the image quality of standard and accelerated T2 weighted turbo-spin-echo (TSE) images of the prostate reconstructed with and without DLR and to find associations between perceived image quality and calculated image characteristics. In a cohort of 47 prospectively enrolled consecutive patients referred for bi-parametric prostate magnetic resonance imaging (MRI), two T2-TSE acquisitions in the transverse plane were acquired on a 3T scanner-a standard T2-TSE sequence and a short sequence accelerated by a factor of two using compressed sensing (CS). The images were reconstructed with and without DLR in super-resolution mode. The image quality was rated in six domains. Signal-to-noise ratio (SNR), and image sharpness were measured. The mean acquisition time was 281±23 s for the standard and 140±12 s for the short acquisition (P<0.0001). DLR images had higher sharpness compared to non-DLR (P<0.001). Short and short-DLR had lower SNR than the standard and standard-DLR (P<0.001). The perceived image quality of short-DLR was rated better in all categories compared to the standard sequence (P<0.001 to P=0.004). All domains of subjective evaluation were correlated with measured image sharpness (P<0.001). T2-TSE acquisition of the prostate accelerated using CS combined with DLR reconstruction provides images with increased sharpness that have a superior quality as perceived by human readers compared to standard T2-TSE. The perceived image quality is correlated with measured image contrast.

Inversion recovery and saturation recovery pulmonary vein MR angiography using an image based navigator fluoro trigger and variable-density 3D cartesian sampling with spiral-like order.

Contrast enhanced pulmonary vein magnetic resonance angiography (PV CE-MRA) has value in atrial ablation pre-procedural planning. We aimed to provide high fidelity, ECG gated PV CE-MRA accelerated by variable density Cartesian sampling (VD-CASPR) with image navigator (iNAV) respiratory motion correction acquired in under 4min. We describe its use in part during the global iodinated contrast shortage. VD-CASPR/iNAV framework was applied to ECG-gated inversion and saturation recovery gradient recalled echo PV CE-MRA in 65 patients (66 exams) using .15mmol/kg Gadobutrol. Image quality was assessed by three physicians, and anatomical segmentation quality by two technologists. Left atrial SNR and left atrial/myocardial CNR were measured. 12 patients had CTA within 6months of MRA. Two readers assessed PV ostial measurements versus CTA for intermodality/interobserver agreement. Inter-rater/intermodality reliability, reproducibility of ostial measurements, SNR/CNR, image, and anatomical segmentation quality was compared. The mean acquisition time was 3.58 ± 0.60min. Of 35 PV pre-ablation datasets (34 patients), mean anatomical segmentation quality score was 3.66 ± 0.54 and 3.63 ± 0.55 as rated by technologists 1 and 2, respectively (p = 0.7113). Good/excellent anatomical segmentation quality (grade 3/4) was seen in 97% of exams. Each rated one exam as moderate quality (grade 2). 95% received a majority image quality score of good/excellent by three physicians. Ostial PV measurements correlated moderate to excellently with CTA (ICCs range 0.52-0.86). No difference in SNR was observed between IR and SR. High quality PV CE-MRA is possible in under 4min using iNAV bolus timing/motion correction and VD-CASPR.

Empirical Research of Professional Creativity of the Head of Educational Institution

The aim of our research is to show the concepts of “professional creativity” and “creativity in the process of professional activity”; to organize the experimental research and to analyze its results; to describe the processes cause a creative reinterpretation of stereotypes – meaning-making – and changes in the entire life process – life-making; to show the results of empirical researches of professional creativity of the head of educational institutions. Methods of the research. The following theoretical methods of the research were used to solve the tasks formulated in the article: a categorical method, structural and functional methods, the methods of the analysis, systematization, modeling and generalization. The experimental method was the method of organizing empirical research. The results of the research. We proved, that if there was no personal meaning in the process of professional activity, for the sake of which professional activity would be carried out, and only the objective orientation of this activity was expressed. Then such activity would not take the form of creative activity, it would not reflect the actual spiritual search on oneself that is meaningful for a person. The internal objective determinants, the objective orientation of the process of professional activity allows the manager to find his/her own personal meaning, and only when the manager clearly understands why he/she will carry out creative activity, its goals and values will be determined. Only in the case when the process of professional creativity acquires a personally significant meaning for the manager, only then this activity can be considered in a creative aspect, in the paradigm of the manager’s acquisition of personal meanings and the formation of his/her creative individuality. Thus, the professional creativity of a manager is understood by us as a conscious, purposeful, active process of the unique activity of its kind, aimed at finding a new, independent, innovative and original way of managing the activities of subordinates with the aim of highly effective creative resolution of managerial tasks and problems. Conclusions. The results of professional creativity are: a new understanding of the subject of activity – the creation of new ideas, programs, concepts, projects, paradigms, aimed at obtaining fundamentally new results, which make it possible to involve a wider social community in creative cooperation; the emergence of new ways of carrying out professional activities, hitherto unknown technologies, activity algorithms, etc. Professional creativity of the manager is accompanied by constant personal development – the need for new, original, non-standard and unique ideas.

Modified respiratory-triggered SPACE sequences for magnetic resonance cholangiopancreatography

BackgroundRespiratory-triggered (RT) and breath-hold are the most common acquisition modalities for magnetic resonance cholangiopancreatography (MRCP). The present study compared the three different acquisition modalities for optimizing the use of MRCP in patients with diseases of the pancreatic and biliary systems. Materials and methodsThree MRCP acquisition modalities were used in this study: conventional respiratory-triggered sampling perfection with application-optimized contrasts using different flip evolutions (RT-SPACE), modified RT-SPACE, and breath-hold (BH)-SPACE. Fifty-eight patients with clinically suspected pancreatic and biliary system disease were included. All image data were acquired on a 1.5 T MR. Scan time and image quality were compared between the three acquisition modalities. Friedman test, which was followed by post-hoc analysis, was performed among triple-scan protocol. ResultsThere was a significant difference in the mean acquisition time among conventional RT-SPACE, modified RT-SPACE, and BH-SPACE (167.41±32.11 seconds vs 50.84±73.78 seconds vs 18.00 seconds, P <0.001). Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were also significantly different among the three groups (P <0.001). The SNR and CNR were higher in the RT-SPACE group than in the BH-SPACE group (P <0.05). However, there were no statistically significant differences (P >0.05) among the 3 groups regarding quality of overall image, image clarity, background inhibition, and visualization of the pancreatic and biliary system. ConclusionsMRCP acquisition with the modified RT-SPACE sequence greatly shortens the acquisition time with comparable quality images. The MRCP acquisition modality could be designed based on the patient's situation to improve the examination pass rate and obtain excellent images for diagnosis.

Diagnosis of acute pulmonary embolism: when photon-counting-detector CT replaces energy-integrating-detector CT in daily routine.

To compare the diagnostic approach of acute pulmonary embolism (PE) with photon-counting-detector CT (PCD-CT) and energy-integrating-detector CT (EID-CT). Two cohorts underwent CT angiographic examinations with EID-CT (Group 1; n = 158) and PCD-CT (Group 2; n = 172), (b) with two options in Group 1, dual energy (Group 1a) or single energy (Group 1b) and a single option in Group 2 (spectral imaging with single source). In Group 2, all patients benefited from spectral imaging, only accessible to 105 patients (66.5%) in Group 1, with a mean acquisition time significantly shorter (0.9 ± 0.1 s vs 4.0 ± 0 .3 s; p < 0.001) and mean values of CTDIvol and DLP reduced by 46.3% and 47.7%, respectively. Comparing the quality of 70 keV (Group 2) and averaged (Group 1a) images: (a) the mean attenuation within pulmonary arteries did not differ (p = 0.13); (b) the image noise was significantly higher (p < 0.001) in Group 2 with no difference in subjective image noise (p = 0.29); and (c) 89% of examinations were devoid of artifacts in Group 2 vs 28.6% in Group 1a. The percentage of diagnostic examinations was 95.2% (100/105; Group 1a), 100% (53/53; Group 1b), and 95.3% (164/172; Group 2). There were 4.8% (5/105; Group 1a) and 4.7% (8/172; Group 2) of non-diagnostic examinations, mainly due to the suboptimal quality of vascular opacification with the restoration of a diagnostic image quality on low-energy images. Compared to EID-CT, morphology and perfusion imaging were available in all patients scanned with PCD-CT, with the radiation dose reduced by 48%. PCD-CT enables scanning patients with the advantages of both spectral imaging, including high-quality morphologic imaging and lung perfusion for all patients, and fast scanning-a combination that is not simultaneously accessible with EID-CT while reducing the radiation dose by almost 50%.

Desafíos a los que se enfrentan los radiólogos recién titulados en sus primeras prácticas clínicas en el suroeste de Nigeria

Background: Formal qualification does not rule out the challenges a radiographer may face by virtue of being new in the clinical practice, and does not necessarily mean acquisition of the needed competency to practice. This study was designed to evaluate challenges encountered by newly qualified Radiographers in their early clinical practice in Southwestern Nigeria. Materials and methods: A descriptive cross-sectional study was conducted among 360 newly qualified Radiographers selected hospitals in South West Nigeria. A well-designed questionnaire was used for data collection and it was analysed with descriptive and inferential statistics. Results: The major communication challenges were: effective communication with patients and careers (3.8 ± 0.8) and effective communication with members of the team (3.8 ± 1.0). The major clinical challenges identified were: cannot perform special exams unaided (1.7 ± 0.6) and cannot prioritize exams according to urgency (1.6 ± 1.0). The major technical challenges identified were: cannot take remedial actions for poor quality radiograph (2.1 ± 0.5) and restriction from access to some machines (1.9 ± 0.7). The major workload challenges identified were: assignment of too much work (2.0 ± 0.4) and poor supervision of new radiographers by superiors (1.7 ± 0.9). The major welfare challenges identified were delay in salary (2.1 ± 0.7) and difficulty in getting internship placement (2.1 ± 0.6). The result from the Chi-square test revealed that there were no statistically significant relationships between the challenges faced by newly qualified radiographers in their early clinical practice and their categories (χ2 =4.806, df=2, p= 0.09).Conclusion: Newly qualified radiographers faces numerous challenges such as technical, communication, workload, poor supervision as well as welfare challenges. There were no statistically significant relationships between the challenges faced by newly qualified radiographers in their early clinical practice and their categories. The study, therefore, recommends the need to create a formal mentorship program for newly qualified radiographers, to provide them with guidance and support. There is also need to provide opportunities for continued professional development for newly qualified radiographers, such as workshops or courses. Also, more staff should be employed so that the workloads are evenly distributed among the radiographers on staff.

On the issue of formal assimilation of anglicism nouns in the genus category of the german language system and its national variants

In the conditions of general globalisation, there is a massive consolidation of Anglicisms in all languages, including the German language with its national variants. The study of this process is topical and corresponds to modern priority scientific directions. Formal assimilation is an aspect of loaning foreign language material by a receptor language. It is this that allows foreign language material to gain a foothold in the system of the borrowing language. However, the German language we consider to be a receptor language, is not a monosystem formation due to its including of national variants. The German literary language is a potential abstract archsystem realised in three directions, sovereign systems of the German language (the German language of Germany, the Austrian and the Swiss varieties of the German literary language). The nature of the German language greatly influences the results of formal assimilation of borrowed material, since they will vary depending on the usage. Fluctuations in national variants arise both at the phonetic, lexical, grammatical, word-formation level, and can manifest themselves in relation to the processes of borrowing and Germanisation of foreign language material. This article studies and describes deviations and variations in the results of the formal assimilation of Anglicisms-nouns in the genus category, functioning in the national varieties of the German language of Austria and Switzerland in comparison with the German language of Germany. The acquisition of generic categorical meaning by borrowed units plays an important role in the German language system, since belonging to a certain grammatical gender is a mandatory and constant indicator of the part of speech “noun” and predetermines the further assimilation of the borrowed unit in the receptor language.