bluuebunny/crossref_metadata_2025 huggingface dataset:
Local super-resolution imaging of foveated areas in super-oscillating optical fields
Authors: Mu Yu , Chang Jun , Wu Yunan , Ma Ning , Zou Lijun , Xue Fangjia , Zhao Shangnan
Published: March 2023

Herein, we propose a super-oscillation optical field foveated local super-resolution imaging method. Firstly, the post-diffraction integral equation of the foveated modulation device is constructed, the objective function and constraints are established, and the structural parameters of the amplitude modulation device are optimally solved by using genetic algorithm. Secondly, the solved data have been input into the software for point diffusion function analysis. We have studied the super-resolution performance of different ring band amplitude types, and find the 8-ring 0-1 amplitude type has the best super-resolution performance. Finally, the principle experimental device is built according to the simulation parameters, and the super-oscillatory device parameters is loaded onto the amplitude type spatial light modulator for the principle experiments, in which the super-oscillation foveated local super-resolution imaging system is able to perform high image contrast imaging in the whole field of view and super-resolution imaging in the foveated field of view area. As a result, this method achieves the 1.25 times super-resolution magnification in the foveated field of view area, which realizes the super-resolutio n imaging of local field while keeping the resolution of other fields unchanged. Experiments verify the feasibility and effectiveness of our system.
Identification of blurred terahertz images by improved cross-layer convolutional neural network
Authors: Chen Zhichao , Wang Cuizhen , Feng Jiaxuan , Zou Zhiyong , Jiang Fengting , Liu Haiqing , Jie Yinxian
Published: March 2023

Terahertz imaging technology has been gradually used in space communication, radar detection, aerospace and biomedical fields. Nevertheless, there are still some limits in terahertz image, such as single tone, fuzzy texture features, poor image resolution and less data, which seriously affect the application and popularization of Terahertz image technology in many fields. Traditional convolutional neural network (CNN) is an effective method for image recognition, but it is limited in highly blurred terahertz image recognition due to the great difference between terahertz image and traditional optical image. This paper presents a proven method for higher recognition rate of blurred terahertz images by using an improved Cross-Layer CNN model with different definition terahertz image dataset. Compared to employing clear image dataset, the accuracy of blurred image recognition can be improved from about 32% to 90% with different definition dataset. Meanwhile, the recognition accuracy of high blurred image can be improved by approximately 5% in contrast to the traditional CNN, which makes the higher recognition ability of neural network. It can be demonstrated that various types of blurred terahertz imaging data can be effectively identified by constructing different definition dataset combined with Cross-Layer CNN. A new method is proved to improve the recognition accuracy of terahertz imaging and application robustness in real scenarios.
Gain enhancement technique for S-band polymer-based waveguide amplifiers
Authors: Fu Yuewu , Sun Tonghe , Li Jun , Tang Ying , Yang Yu , Tao Siliang , Yin Jing , Wang Fei , Zhang Daming , Qin Guanshi , Wang Xunsi , Zhao Dan , Qin Weiping
Published: March 2023

The S-band polymer-based waveguide amplifier has been fabricated, but how to improve the gain performance remains a big challenge. Here, using the technique of establishing the energy transfer between different ions, we successfully improved the efficiency of Tm3+:3F3→3H4 and 3H5→3F4 transitions, resulting in the emission enhancement at 1480 nm and gain improvement in S-band. By doping the NaYF4:Tm,Yb,Ce@NaYF4 nanoparticles into the core layer, the polymer-based waveguide amplifier provided a maximum gain of 12.7 dB at 1480 nm, which was 6 dB higher than previous work. Our results indicated that the gain enhancement technique significantly improved the S-band gain performance and provided guidance for even other communication bands.
Dammann gratings-based truly parallel optical matrix multiplication accelerator
Authors: Ma Guoqing , Yu Junjie , Zhu Rongwei , Zheng Fenglu , Zhou Changhe , Situ Guohai
Published: March 2023

Matrix multiplication (MM) is a fundamental operation in various scientific and engineering computations, as well as in artificial intelligence algorithms. Efficient implementation of MM is crucial for speeding up numerous applications. Photonics presents an opportunity for efficient acceleration of dense matrix computation, owing to its intrinsic advantages, such as huge parallelism, low latency, and low power consumption. However, most optical matrix computing architectures have been limited to realizing single-channel vector–matrix multiplication or using complex configurations to expand the number of channels, which does not fully exploit the parallelism of optics. In this study, we propose a novel, to the best of our knowledge, scheme for the implementation of large-scale two-dimensional optical MM with truly massive parallelism based on a specially designed Dammann grating. We demonstrate a sequence of MMs of 50 pairs of randomly generated 4 × 8 and 8 × 4 matrices in our proof-of-principle experiment. The results indicate that the mean relative error is approximately 0.048, thereby demonstrating optical robustness and high accuracy.
The potential of biofuels from first to fourth generation
Authors: Cavelius Philipp , Engelhart-Straub Selina , Mehlmer Norbert , Lercher Johannes , Awad Dania , Brück Thomas
Published: March 2023

The steady increase in human population and a rising standard of living heighten global demand for energy. Fossil fuels account for more than three-quarters of energy production, releasing enormous amounts of carbon dioxide (CO2) that drive climate change effects as well as contributing to severe air pollution in many countries. Hence, drastic reduction of CO2emissions, especially from fossil fuels, is essential to tackle anthropogenic climate change. To reduce CO2emissions and to cope with the ever-growing demand for energy, it is essential to develop renewable energy sources, of which biofuels will form an important contribution. In this Essay, liquid biofuels from first to fourth generation are discussed in detail alongside their industrial development and policy implications, with a focus on the transport sector as a complementary solution to other environmentally friendly technologies, such as electric cars.
Development of a scoring function for comparing simulated and experimental tumor spheroids
Authors: Herold Julian , Behle Eric , Rosenbauer Jakob , Ferruzzi Jacopo , Schug Alexander
Published: March 2023

Progress continues in the field of cancer biology, yet much remains to be unveiled regarding the mechanisms of cancer invasion. In particular, complex biophysical mechanisms enable a tumor to remodel the surrounding extracellular matrix (ECM), allowing cells to invade alone or collectively. Tumor spheroids cultured in collagen represent a simplified, reproducible 3D model system, which is sufficiently complex to recapitulate the evolving organization of cells and interaction with the ECM that occur during invasion. Recent experimental approaches enable high resolution imaging and quantification of the internal structure of invading tumor spheroids. Concurrently, computational modeling enables simulations of complex multicellular aggregates based on first principles. The comparison between real and simulated spheroids represents a way to fully exploit both data sources, but remains a challenge. We hypothesize that comparing any two spheroids requires first the extraction of basic features from the raw data, and second the definition of key metrics to match such features. Here, we present a novel method to compare spatial features of spheroids in 3D. To do so, we define and extract features from spheroid point cloud data, which we simulated using Cells in Silico (CiS), a high-performance framework for large-scale tissue modeling previously developed by us. We then define metrics to compare features between individual spheroids, and combine all metrics into an overall deviation score. Finally, we use our features to compare experimental data on invading spheroids in increasing collagen densities. We propose that our approach represents the basis for defining improved metrics to compare large 3D data sets. Moving forward, this approach will enable the detailed analysis of spheroids of any origin, one application of which is informingin silicospheroids based on theirin vitrocounterparts. This will enable both basic and applied researchers to close the loop between modeling and experiments in cancer research.
Network models of protein phosphorylation, acetylation, and ubiquitination connect metabolic and cell signaling pathways in lung cancer
Authors: Ross Karen E. , Zhang Guolin , Akcora Cuneyt , Lin Yu , Fang Bin , Koomen John , Haura Eric B. , Grimes Mark
Published: March 2023

We analyzed large-scale post-translational modification (PTM) data to outline cell signaling pathways affected by tyrosine kinase inhibitors (TKIs) in ten lung cancer cell lines. Tyrosine phosphorylated, lysine ubiquitinated, and lysine acetylated proteins were concomitantly identified using sequential enrichment of post translational modification (SEPTM) proteomics. Machine learning was used to identify PTM clusters that represent functional modules that respond to TKIs. To model lung cancer signaling at the protein level, PTM clusters were used to create a co-cluster correlation network (CCCN) and select protein-protein interactions (PPIs) from a large network of curated PPIs to create a cluster-filtered network (CFN). Next, we constructed a Pathway Crosstalk Network (PCN) by connecting pathways from NCATS BioPlanet whose member proteins have PTMs that co-cluster. Interrogating the CCCN, CFN, and PCN individually and in combination yields insights into the response of lung cancer cells to TKIs. We highlight examples where cell signaling pathways involving EGFR and ALK exhibit crosstalk with BioPlanet pathways: Transmembrane transport of small molecules; and Glycolysis and gluconeogenesis. These data identify known and previously unappreciated connections between receptor tyrosine kinase (RTK) signal transduction and oncogenic metabolic reprogramming in lung cancer. Comparison to a CFN generated from a previous multi-PTM analysis of lung cancer cell lines reveals a common core of PPIs involving heat shock/chaperone proteins, metabolic enzymes, cytoskeletal components, and RNA-binding proteins. Elucidation of points of crosstalk among signaling pathways employing different PTMs reveals new potential drug targets and candidates for synergistic attack through combination drug therapy.
Early diagnosis of dengue: Diagnostic utility of the SD BIOLINE Dengue Duo rapid test in Reunion Island
Authors: Maillard Olivier , Belot Jeanne , Adenis Thibault , Rollot Olivier , Adenis Antoine , Guihard Bertrand , Gérardin Patrick , Bertolotti Antoine
Published: March 2023

Background

In Reunion Island, dengue outbreaks have been occurring since 2018. The healthcare facilities are facing the problem of managing a massive influx of patients and a growing care burden. The aim of this study was to evaluate the performance of the SD Bioline Dengue Duo rapid diagnostic test in adults consulting at an emergency department during the 2019 epidemic.

Methodology/Principal findings

This retrospective study of diagnostic accuracy included patients over 18 years old, suspected of dengue, who were admitted to emergency units of the University Hospital of Reunion between the 1st of January and 30th of June, 2019, and were tested for dengue fever with the SD Bioline Dengue Duo rapid diagnostic test and reverse transcriptase polymerase chain reaction. Over the study period, 2099 patients were screened retrospectively. Of them, 671 patients matched the inclusion criteria. The overall rapid diagnostic test performance was 42% for sensitivity and 15% for specificity. The non-structural 1 antigen component had a good specificity of 82% but a low sensitivity of 12%. The immunoglobulin M component had a sensitivity of 28% and a specificity of 33%. Sensitivities were slightly improved beyond the 5th day of illness compared to the early stage for all components, but only the non-structural 1 antigen component had a better specificity of 91%. Furthermore, predictive values were low and post-test probabilities never improved pre-test probabilities in our setting.

Conclusions/Significance

These results suggest that the SD Bioline Dengue Duo RDT did not achieve sufficient performance levels to rule in, or discard, an early point of care dengue diagnosis in the emergency department during the 2019 epidemic in Reunion.
Prevention of relapse in drug sensitive pulmonary tuberculosis patients with and without vitamin D3 supplementation: A double blinded randomized control clinical trial
Authors: Sinha Sanjeev , Thukral Himanshu , Shareef Imtiyaz , Desai Devashish , Singh Binit Kumar , Das Bimal Kumar , Dhooria Sahajal , Sarin Rohit , Singla Rupak , Meena Saroj Kumari , Pandey Ravindra Mohan , Pandey Shivam , Sethi Sunil , Kajal Ashumeet , Yadav Rakesh , Aggarwal Ashutosh Nath , Bhadada Sanjay , Behera Digambar
Published: March 2023

Background

The immunomodulatory effects of vitamin D are widely recognized and a few studies have been conducted to determine its utility in the treatment of tuberculosis, with mixed results. This study was conducted to see if vitamin D supplementation in patients with active pulmonary tuberculosis (PTB) in the Indian population contributed to sputum smear and culture conversion as well as the prevention of relapse.

Methods

This randomized double-blind placebo-controlled trial was conducted in three sites in India. HIV negative participants aged 15–60 years with sputum smear positive PTB were recruited according to the Revised National Tuberculosis Control Program guidelines and were randomly assigned (1:1) to receive standard anti-tubercular treatment (ATT) with either supplemental dose of oral vitamin D3 (60,000 IU/sachet weekly for first two months, fortnightly for next four months followed by monthly for the next 18 months) or placebo with same schedule. The primary outcome was relapse of PTB and secondary outcomes were time to conversion of sputum smear and sputum culture.

Results

A total of 846 participants were enrolled between February 1, 2017 to February 27, 2021, and randomly assigned to receive either 60,000 IU vitamin D3 (n = 424) or placebo (n = 422) along with standard ATT. Among the 697 who were cured of PTB, relapse occurred in 14 participants from the vitamin D group and 19 participants from the placebo group (hazard risk ratio 0.68, 95%CI 0.34 to 1.37, log rank p value 0.29). Similarly, no statistically significant difference was seen in time to sputum smear and sputum culture conversion between both groups. Five patients died each in vitamin D and placebo groups, but none of the deaths were attributable to the study intervention. Serum levels of vitamin D were significantly raised in the vitamin D group as compared to the placebo group, with other blood parameters not showing any significant difference between groups.

Conclusions

The study reveals that vitamin D supplementation does not seem to have any beneficial effect in the treatment of PTB in terms to the prevention of relapse and time to sputum smear and culture conversion.

Trial registration

CTRI/2021/02/030977 (ICMR, Clinical trial registry-India).
How has medical student learning changed with the pivot to online delivery of ophthalmology in the pandemic?
Authors: Ní Gabhann-Dromgoole Joan , Murphy Conor C. , Boland Fiona , Doyle Andrea J. , Pawlikowska Teresa
Published: March 2023

Purpose

This study aimed to measure stakeholder satisfaction with our usual delivery format, which previously relied on a blend of didactic lectures and clinical skills sessions compared to a revised format, which had more emphasis on online learning. We hypothesised that the online flipped classroom (OFC) would facilitate delivery of content in the wake of the pandemic, and result in improved levels of student satisfaction and knowledge gain.

Design

Non randomised intervention study. Group 1 = Traditional delivery (TD) and Group 2 = OFC group.

Methods

A validated course evaluation questionnaire (CEQ) compared perspectives of teaching faculty (n = 5) and students with the traditional delivery (TD) of the 4th year ophthalmology clinical attachment and an OFC approach (TD n = 129 v OFC n = 114).

Results

The OFC group (n = 114; response rate = 24.6%) reported significantly reduced satisfaction with staff motivation of students and provision of feedback, compared to TD (n = 129; response rate = 17.8%). OFC students also felt it was harder to determine what standard of work was expected and found the course less beneficial at helping develop problem-solving skills. Students were dissatisfied with the level of choice afforded by the OFC, specifically how they would learn and assessment options. No significant difference in exam score was observed between the TD and OFC groups. For faculty (n = 5), there was no evidence of a difference between OFC and TD.

Conclusions

Students indicated a preference for the TD compared to the OFC approach. However, both delivery approaches led to comparable student performances as determined by MCQ examination.
Human influenza A virus H1N1 in marine mammals in California, 2019
Authors: Plancarte Magdalena , Kovalenko Ganna , Baldassano Julie , Ramírez Ana L. , Carrillo Selina , Duignan Pádraig J. , Goodfellow Ian , Bortz Eric , Dutta Jayeeta , van Bakel Harm , Coffey Lark L.
Published: March 2023

From 2011–2018, we conducted surveillance in marine mammals along the California coast for influenza A virus (IAV), frequently detecting anti-influenza antibodies and intermittently detecting IAV. In spring 2019, this pattern changed. Despite no change in surveillance intensity, we detected IAV RNA in 10 samples in March and April, mostly in nasal and rectal swabs from northern elephant seals (Mirounga angustirostris). Although virus isolation was unsuccessful, IAV sequenced from one northern elephant seal nasal swab showed close genetic identity with pandemic H1N1 IAV subclade 6B.1A.1 that was concurrently circulating in humans in the 2018/19 influenza season. This represents the first report of human A(H1N1)pdm09 IAV in northern elephant seals since 2010, suggesting IAV continues to spill over from humans to pinnipeds.
Whole body insulin sensitivity is increased in systemic sclerosis
Authors: Ciaffi Jacopo , Ruscitti Piero , Di Cola Ilenia , Pavlych Viktoriya , Italiano Noemi , Gentile Martina , Huizinga Tom , de Vries-Bouwstra Jeska K. , Ursini Francesco , Cipriani Paola
Published: March 2023

Objectives

In the present study, we aimed to evaluate whole-body insulin sensitivity in systemic sclerosis (SSc) patients and to compare the results with controls with no autoimmune rheumatic disease (non-ARD) and with patients affected by rheumatoid arthritis (RA).

Methods

In all patients and controls, oral glucose tolerance test (OGTT) was performed according to the World Health Organization (WHO) recommendations. Plasma glucose and insulin concentrations were measured at time 0 and then after 30, 60, 90, and 120 minutes. Whole-body insulin sensitivity (ISI), insulinogenic index (IGI), oral disposition index (ODI), and insulin resistance (HOMA-IR) were estimated accordingly.

Results

A total of 41 SSc patients were evaluated and, for comparison, 41 individuals with RA and 82 non-ARD control patients were recruited. OGTT yielded a proportion of normotolerant individuals among SSc patients higher than in RA controls (p = 0.040) but lower than in the non-ARD group (p = 0.028). The ISI was significantly higher in SSc patients compared with RA controls (p <0.001) and with non-ARD patients (p <0.001). Significant differences emerged also when analysing the HOMA-IR, which was lower in SSc patients than in RA (p <0.001) and non-ARD (p <0.001) groups. Additionally, IGI was lower in SSc patients compared with RA (p = 0.011) and with non-ARD controls (p <0.001), whereas ODI was not significantly different between groups.

Conclusions

Interestingly, we found that SSc patients are more insulin sensitive than those with RA and even than individuals without inflammatory diseases. In contrast, no significant difference was found in terms of β-cell function.
Chemosensory continuity from prenatal to postnatal life in humans: A systematic review and meta-analysis
Authors: Ustun Beyza , Covey Judith , Reissland Nadja
Published: March 2023

Throughout pregnancy, fetuses are exposed to a range of chemosensory inputs influencing their postnatal behaviors. Such prenatal exposure provides the fetus with continuous sensory information to adapt to the environment they face once born. This study aimed to assess the chemosensory continuity through a systematic review and meta-analysis of existing evidence on chemosensory continuity from prenatal to first postnatal year. Web of Science Core. Collections, MEDLINE, PsycINFO, EBSCOhost ebook collection was searched from 1900 to 2021. Studies identified from the search were grouped according to type of stimuli the fetuses were exposed to prenatally that the neonatal infants’ responses to were being evaluated, namely flavors transferred from the maternal diet, and the odor of their own amniotic fluid. Of the 12 studies that met the eligibility criteria for inclusion (k = 6, k = 6, respectively in the first and the second group of studies), and eight studies (k = 4, k = 4, respectively) provided sufficient data suitable for meta-analysis. Infants, during their first year of life, oriented their heads for significantly longer durations in the direction of the prenatally experienced stimuli with large pooled effect sizes (flavor stimuli, d = 1.24, 95% CI [0.56, 1.91]; amniotic fluid odor, d = 0.853; 95% CI [.632, 1.073]). The pooled effect size for the duration of mouthing behavior was significant in response to prenatal flavor exposure through maternal diet (d = 0.72; 95% CI [0.306, 1.136]), but not for the frequency of negative facial expressions (d = -0.87, 95% CI [-2.39, 0.66]). Postnatal evidence suggests that there is a chemosensory continuity from fetal to the first year of postnatal life.
Initial mean arterial blood pressure (MABP) measurement is a risk factor for mortality in hypertensive COVID-19 positive hospitalized patients
Authors: Yangchen Tenzin , Koraishy Farrukh M. , Xu Chang , Hou Wei , Rohatgi Rajeev
Published: March 2023

Background

Hypertension (HTN) is associated with severe COVID-19 infection; however, it remains unknown if the level of blood pressure (BP) predicts mortality. We tested whether the initial BP in the emergency department of hospitalized patients portends mortality in COVID-19 positive(+) patients.

Methods

Data from COVID-19(+) and negative (-) hospitalized patients at Stony Brook University Hospital from March to July 2020 were included. The initial mean arterial BPs (MABPs) were categorized into tertiles (T) of MABP (65–85 [T1], 86–97 [T2] and ≥98 [T3] mmHg). Differences were evaluated using univariable (t-tests, chi-squared) tests. Multivariable (MV) logistic regression analyses were computed to assess links between MABP and mortality in hypertensive COVID-19 patients.

Results

1549 adults were diagnosed with COVID-19 (+) and 2577 tested negative (-). Mortality of COVID-19(+) was 4.4-fold greater than COVID-19(-) patients. Though HTN prevalance did not differ between COVID-19 groups, the presenting systolic BP, diastolic BP, and MABP were lower in the COVID-19(+) vs (-) cohort. When subjects were categorized into tertiles of MABP, T2 tertile of MABP had the lowest mortality and the T1 tertile of MABP had greatest mortality compared to T2; however, no difference in mortality was noted across tertiles of MABP in COVID-19 (-). MV analysis of COVID-19 (+) subjects exposed death as a risk factor for T1 MABP. Next, the mortality of those with a historic diagnosis of hypertension or normotension were studied. On MV analysis, T1 MABP, gender, age, and first respiratory rate correlated with mortality while lymphocyte count inversely correlated with death in hypertensive COVID-19 (+) patients while neither T1 nor T3 categories of MABP predicted death in non-hypertensives.

Conclusions

Low-normal admitting MABP in COVID-19 (+) subjects with a historical diagnosis of HTN is associated with mortality and may assist in identifying those at greatest mortality risk.
Innovation in hyperlink and social media networks: Comparing connection strategies of innovative companies in hyperlink and social media networks
Authors: Arifi Dorian , Resch Bernd , Kinne Jan , Lenz David
Published: March 2023

This paper seeks to unveil how (geospatial) connection strategies associated with business innovation, differ between geolocated social media and hyperlink company networks. Thereby, we provide a first step towards understanding connection strategies of innovative companies on social media platforms. For this purpose, we build a hyperlink and Twitter follower network for 11,892 companies in the information technology (IT) sector and compare them along four dimensions. First, underlying network structures were assessed. Second, we asserted information flow patterns between companies with the help of centrality measures. Third, geographic and cognitive proximities of companies were compared. Fourth, the influence of company characteristics was examined through linear and logistic regression models. This comparison revealed, that on a general level the basic connection patterns of the hyperlink and Twitter network differ. Nevertheless, the geospatial dimension (geographic proximity) and the knowledge base of a company (cognitive proximity) appear to have a similar influence on the decision to connect with other companies on Twitter and via hyperlinks. Further, the results suggest that innovative companies most likely align their connection strategies across hyperlink and Twitter networks. Thus, business innovation might effect connection strategies across online company networks in a comparable manner.
Exact solutions of (1 + 1)-dimensional integro-differential Ito, KP hierarchy, CBS, MCBS and modified KdV-CBS equations
Authors: Amin Amina , Naeem Imran , Khan Adnan
Published: March 2023

The present study computes the Lie symmetries and exact solutions of some problems modeled by nonlinear partial differential equations. The (1 + 1)-dimensional integro-differential Ito, the first integro-differential KP hierarchy, the Calogero-Bogoyavlenskii-Schiff (CBS), the modified Calogero-Bogoyavlenskii-Schiff (CBS), and the modified KdV-CBS equations are some of the problems for which we want to find new exact solutions. We employ similarity variables to reduce the number of independent variables and inverse similarity transformations to obtain exact solutions to the equations under consideration. The sine-cosine method is then utilized to determine the exact solutions.
A standardized database of Chinese emotional short videos based on age and gender differences
Authors: Duan Danting , Zhong Wei , Ran Shuang , Ye Long , Zhang Qin
Published: March 2023

Most of the existing emotion elicitation databases use the film clips as stimuli and do not take into account the age and gender differences of participants. Considering the short videos have the advantages of short in time, easy to understand and strong emotional appeal, we choose them to construct a standardized database of Chinese emotional short videos by the joint analysis of age and gender differences. Two experiments are performed to establish and validate our database. In the Experiment 1, we selected 240 stimuli from 2700 short videos and analyzed the subjective evaluation results of 360 participants with different ages and genders. As a result, a total of 54 short videos with three categories of emotions were picked out for 6 groups of participants, including the male and female respectively aged in 20-24, 25-29 and 30-34. In the Experiment 2, we recorded the EEG signals and subjective experience scores of 81 participants while watching different video stimuli. Both the results of EEG emotion recognition and subjective evaluation indicate that our database of 54 short videos can achieve better emotion elicitation effects compared with film clips. Furthermore, the targeted delivery of specific short videos has also been verified to be effective, helping the researchers choose appropriate emotional elicitation stimuli for different participants and promoting the study of individual differences in emotion responses.
Detecting CTP truncation artifacts in acute stroke imaging from the arterial input and the vascular output functions
Authors: de la Rosa Ezequiel , Sima Diana M. , Kirschke Jan S. , Menze Bjoern , Robben David
Published: March 2023

Background

Current guidelines for CT perfusion (CTP) in acute stroke suggest acquiring scans with a minimal duration of 60-70 s. But even then, CTP analysis can be affected by truncation artifacts. Conversely, shorter acquisitions are still widely used in clinical practice and may, sometimes, be sufficient to reliably estimate lesion volumes. We aim to devise an automatic method that detects scans affected by truncation artifacts.

Methods

Shorter scan durations are simulated from the ISLES’18 dataset by consecutively removing the last CTP time-point until reaching a 10 s duration. For each truncated series, perfusion lesion volumes are quantified and used to label the series as unreliable if the lesion volumes considerably deviate from the original untruncated ones. Afterwards, nine features from the arterial input function (AIF) and the vascular output function (VOF) are derived and used to fit machine-learning models with the goal of detecting unreliably truncated scans. Methods are compared against a baseline classifier solely based on the scan duration, which is the current clinical standard. The ROC-AUC, precision-recall AUC and the F1-score are measured in a 5-fold cross-validation setting.

Results

The best performing classifier obtained an ROC-AUC of 0.982, precision-recall AUC of 0.985 and F1-score of 0.938. The most important feature was the AIFcoverage, measured as the time difference between the scan duration and the AIF peak. When using the AIFcoverage to build a single feature classifier, an ROC-AUC of 0.981, precision-recall AUC of 0.984 and F1-score of 0.932 were obtained. In comparison, the baseline classifier obtained an ROC-AUC of 0.954, precision-recall AUC of 0.958 and F1-Score of 0.875.

Conclusions

Machine learning models fed with AIF and VOF features accurately detected unreliable stroke lesion measurements due to insufficient acquisition duration. The AIFcoverage was the most predictive feature of truncation and identified unreliable short scans almost as good as machine learning. We conclude that AIF/VOF based classifiers are more accurate than the scans’ duration for detecting truncation. These methods could be transferred to perfusion analysis software in order to increase the interpretability of CTP outputs.
Desipramine enhances the stability of atherosclerotic plaque in rabbits monitored with molecular imaging
Authors: Zhao Min , You Baiyang , Wang Xiaole , Huang Jin , Zhou Ming , Shi Ruizheng , Zhang Guogang
Published: March 2023

Acid sphingomyelinase (ASM) promotes atherogenesis and acute cardiovascular events. We previously demonstrated ASM inhibitor desipramine attenuated oxidized-LDL-induced macrophage apoptosis in vitro. Here, we aim to determine whether ASM-mediated apoptosis in plaque improves stability in vivo. In this study, rabbits with abdominal aorta balloon injury and a 12-week high-cholesterol diet (HCD) were used to simulate an atherosclerotic plaque model. Atherosclerotic rabbits received oral administration of saline (Control group), atorvastatin (Ator group), or desipramine (DES group). ASM activity and ceramide level were measured by ultra-performance liquid chromatography (UPLC). Plaque morphology was assessed by histochemistry and immunohistochemistry. Apoptosis was evaluated by SPECT/CT imaging of 99mTc-duramycin uptake and TUNEL. We found that increasing ASM activity and ceramide level in atherosclerotic rabbits was abated by additional atorvastatin and desipramine treatment. Meanwhile, the DES and Ator groups were similar in plaque stability, with smaller plaque size, areas of macrophages, higher smooth muscle cell content, and decreased apoptosis and matrix metalloproteinase (MMP) activities relative to the Control group. 99mTc-duramycin uptake of rabbit aorta was significantly higher in Control than in the Normal group, while it was reduced by desipramine and atorvastatin administration. Moreover, the uptake of 99mTc-duramycin positively correlated with apoptotic cell number, macrophage infiltration, and plaque instability. The present study demonstrated that desipramine exerted plaque-stabilizing effects partially by suppressing apoptosis and MMP activity in a rabbit model. And 99mTc-duramycin SPECT/CT imaging allowed noninvasively monitoring of atherosclerotic disease and evaluation of anti-atherosclerotic therapy.
Identification of cancer-related genes FGFR2 and CEBPB in choledochal cyst via RNA sequencing of patient-derived liver organoids
Authors: Ye Yongqin , Lui Vincent Chi Hang , Babu Rosana Ottakandathil , Wu Zhongluan , Wu Weifang , Chung Patrick Ho Yu , Wong Kenneth Kak Yuen , Wang Bin , Tam Paul Kwong Hang
Published: March 2023

Background

Choledochal cysts (CC) are congenital bile duct anomalies with 6–30% risk for developing bile duct cancer. However, the molecular mechanisms underlying cancer risk of CC are unknown. We sought to identify the gene expression changes underlying the cancer risk of CC patients.

Methods

Liver organoids (n = 51) were generated from liver/bile duct biopsies of CC (n = 7; type I) and hepatoblastoma (n = 5; HB: non-tumor & tumor) for RNA sequencing. Bioinformatics analysis was conducted to identify differentially expressed cancer-related genes in CC and controls. We compared CC with non-cancerous and cancerous controls, normal adjacent non-tumor region of hepatoblastoma (HB) liver as non-cancerous control and tumor region as non-CC cancer control (HB-tumor). Reverse transcription real-time quantitative PCR (RT-qPCR) verification and immunohistochemistry of selected genes was conducted in additional CC and HB liver biopsies.

Findings

HB non-tumor and HB tumor organoids displayed distinct gene expression profiles. Expression profiling separated CC organoids into two clusters, one overlapping with HB non-tumor and the other one with HB tumor organoids. Genes selected based on their log2FoldChange values for RT-qPCR verification in 31 CC and 11 HB non-tumor liver tissues revealed significantly elevated expression of FGFR2 in 7 and CEBPB in 2 CC liver tissues (CC vs HB: 4.082 vs. 0.7671, p<0.01; 2.506 vs. 1.210, p<0.01). Distinctive positive staining in bile ducts were seen in CC, HB tumor and non-tumor liver tissues for FGFR2 and CEBPB. Percentages of CEBPB-immuno-positive or FGFR2-immuno-positive bile duct cells in CC and HB-tumor liver were higher than that in HB non-tumor liver.

Interpretation

The study identified dysregulated genes related to cancer pathways in CC patients suggesting cancer risk. The findings suggest that the elevated expression of FGFR2 and CEBPB in liver may contribute to cancer development in CC patients.
Prevalence of antimicrobial resistance and virulence genes in Klebsiella pneumoniae and Congenetic Raoultella Isolates from captive giant pandas
Authors: Li Yan , Sun Yang , Sun Shi-wen , Liang Bing , Jiang Bo-wen , Feng Na , Liu Jun , Ji Xue
Published: March 2023

To study antimicrobial resistance and virulence genes of Klebsiella pneumoniae and Raoultella strains isolated from captive giant pandas. Non-duplicate fecal samples were collected from 128 giant pandas during 2017–2019. All isolated microbial strains were tested for antimicrobial drug susceptibility using BD verification panels. Four extended-spectrum β-lactamase resistance genes, nine virulence genes and six capsular serotype genes were detected using PCR. 42 K. pneumoniae and nine Raoultella strains were isolated from different giant pandas. Antibiotic resistance rates were 1.9%–23.5%, except for ampicillin, and 7.8% of the isolates were multidrug-resistant to 7–10 antibiotic classes. This is the first time that a multidrug-resistant R. ornithinolytica strain has been isolated from captive giant pandas. The blaTEM, blaCTX-M, blaSHV and blaDHA genes were detected in four MDR ESBL- K. pneumoniae strains. The rmpA, iutA, ybtS, iroN and iroB genes were positively detected in 11.7% of the isolates. Capsular serotype (K2, K5, K54 and K57) genes were all detected in four K. pneumoniae strains, and one was identified as hypervirulent. This study showed that MDR ESBL- K. pneumoniae, hypervirulent K. pneumoniae, MDR R. ornithinolytica and the colistin-resistant strain may pose risks to captive giant pandas and their keepers, and that the diversity of antibiotic resistance and virulence genes in Klebsiella and Raoultella should be monitored regularly.
Intracellular cGMP increase is not involved in thyroid cancer cell death
Authors: Alessandro Sara D’ , Paradiso Elia , Lazzaretti Clara , Sperduti Samantha , Perri Carmela , Antoniani Francesco , Righi Sara , Simoni Manuela , Brigante Giulia , Casarini Livio
Published: March 2023

Introduction

Type 5 phosphodiesterase (PDE5) inhibitors (PDE5i) lead to intracellular cyclic-guanosine monophosphate (cGMP) increase and are used for clinical treatment of erectile dysfunction. Studies found that cGMP may up/downregulate the growth of certain endocrine tumor cells, suggesting that PDE5i could impact cancer risk.

Aim

We evaluated if PDE5i may modulate thyroid cancer cell growth in vitro.

Materials and methods

We used malignant (K1) and benign (Nthy-ori 3–1) thyroid cell lines, as well as the COS7 cells as a reference model. Cells were treated 0–24 h with the PDE5i vardenafil or the cGMP analog 8-br-cGMP (nM-μM range). cGMP levels and caspase 3 cleavage were evaluated by BRET, in cGMP or caspase 3 biosensor-expressing cells. Phosphorylation of the proliferation-associated extracellularly-regulated kinases 1 and 2 (ERK1/2) was evaluated by Western blotting, while nuclear fragmentation by DAPI staining. Cell viability was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.

Results

Both vardenafil and 8-br-cGMP effectively induced dose-dependent cGMP BRET signals (p≤0.05) in all the cell lines. However, no differences in caspase 3 activation occurred comparing PDE5i-treated vs untreated cells, at all concentrations and time-points tested (p>0.05). These results match those obtained upon cell treatment with 8-br-cGMP, which failed in inducing caspase 3 cleavage in all the cell lines (p>0.05). Moreover, they reflect the lack of nuclear fragmentation. Interestingly, the modulation of intracellular cGMP levels with vardenafil or the analog did not impact cell viability of both malignant and benign thyroid tumor cell lines, nor the phosphorylation of ERK1/2 (p>0.05).

Conclusions

This study demonstrates that increased cGMP levels are not linked to cell viability or death in K1 and Nthy-ori 3–1 cell lines, suggesting that PDE5i do not impact the growth of thyroid cancer cells. Since different results were previously published, further investigations are recommended to clarify the impact of PDE5i on thyroid cancer cells.
Synthesis, Structural and Antibacterial Activity of Zn1-xNixFe2O4 Nanoparticles
Authors: Badabagni Pradeep Raju , Nayakanti Devanna
Published: March 2023

In present work, nickel doped zinc ferrite nanoparticles were prepared via hydrothermal technique. The prepared nanopowders undergone various characterization techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier-transform infrared spectroscope (FTIR), vibrating sample magnetometer (VSM) and antimicrobial activity. Further, the XRD analysis revealed that the presence of sharp diffraction peaks and cubic-structure of the prepared samples. SEM analysis revealed that there is a significant degree of agglomeration in the samples, whereas VSM studies revealed the magnetic behaviour and cation distribution in the prepared samples. The prepared nanopowder has also been evaluated for its antimicrobial properties against both Gram-negative bacteria (Enterobacter aerogenes) and Gram-positive bacteria (Enterococcus faecalis). An increasing in the ratio of nickel to zinc in ferrite nanoparticles led to an evident rise in their activity. These nanoparticles with enhanced structure and antimicrobial properties could find applications in hygiene, therapeutic and textile fields.
Nitrosamine Impurities: Assessing Concerns through Case Studies: A Review
Authors: Jena Monalisha , Mukadam Misbah , Telange Divya , Dolas Ruchika , Ramaa C.S.
Published: March 2023

N-nitrosamines are potential human carcinogens that can be ingested from a range of known sources, including food, drinking water, tobacco smoke and cosmetic goods. Remarkably, their prevalence in medicinal products went undetected until mid-2018. These contaminants were first detected in the active pharmaceutical ingredient (API) of valsartan and other sartan medicines were eventually implicated. The regulatory response to the nitrosamines issue included a recommendation to all marketing authorization holders (MAHs) for human medicinal products containing chemically synthesized active pharmaceutical ingredients to evaluate the potential hazards of nitrosamines in their products and implement appropriate risk mitigation checks and balances. The objective of this review is to investigate various realms associated with investigating how these genotoxic and carcinogenic impurities may be formed during the manufacture or preservation/storage of a wide range of drugs, including sartans (losartan, valsartan), anti-diabetics (metformin, pioglitazone) and a few antacids (ranitidine) and a thorough literature review on case-studies, drug-excipient interactions, metabolic activation and other prospects.
Assessment of Tear Film Parameters in Patients with Type 2 Diabetes Mellitus
Authors: Amruthlal Yellamelli  , Nitin Batra  , Gurvinder Kaur  , Samson Rajpal
Published: March 2023

BACKGROUND

Dry eye is a condition of tear film which occurs either due to tear deficiency or excessive evaporation of tears which causes damage to the interpalpebral ocular surface and is associated with ocular discomfort symptoms. This ocular disorder is common among general population with a prevalence of 28% among adults. Although diabetic retinopathy and diabetic cataracts are commonly known complications of diabetes, dry eye syndrome or keratoconjunctivitis sicca is also prevalent in diabetic individuals. The prevalence of dry eye in patients with type 2 diabetes mellitus has been reported to be 54%. The diagnosis of dry eye can be determined by decreased tear film stability, assessed by the tear film break up time (TBUT), and reduced tear secretion evaluated by Schirmer’s test.

Aims and Objectives

To assess the tear film parameters in patients with type 2 diabetes mellitus.

To assess the co-relation of tear film parameters with duration of diabetes and HbA1c levels.

METHODS

A total of 100 eyes of patients with type 2 diabetes mellitus subjects and 100 eyes of non-diabetic age group and gender matched controls, were included in the study. The study was conducted from October 2021 to August 2022. Duration of diabetes mellitus and HbA1c values were documented on all subjects.

RESULTS

The mean age of the study group and the control group was 60.24 years and 58.32 years respectively. There were more males enrolled than females in both the study group and the control group. Among the study group, the mean values of Schirmer’s test-1 and Schirmer’s test-2 were 20.81±7.2 mm and 12.88±6.01 mm respectively. The values of both Schirmer’s test-1 and Schirmer’s test-2 were lower in the diabetics as compared to the controls. The mean value of TBUT (8.7±3.1 sec) was significantly reduced in diabetic patients as compared to the controls. There was a strong negative correlation of Schirmer’s test-1, Schirmer’s test-2 and TBUT with the duration of diabetes mellitus and with the levels of HbA1c.

CONCLUSIONS

The incidence of diabetes and dry eye syndrome as separate disease entities is on the rise at present. Dry eye syndrome in diabetes further compromises the quality of life of the patients and thus, should be diagnosed and treated early.
Scalp Swelling a Rare Presentation of Disseminated Lung Carcinoma
Authors: Hrushikesh Umakant Kharosekar  , Nimesh Jain  , Vernon L. Velho
Published: March 2023

Subcutaneous metastatic nodules are uncommon presentation of underlying malignancy. Cutaneous metastasis is seen in less than 4% cases of all malignancies and is usually seen following initial diagnosis. Lung carcinoma has higher predisposition for bony metastasis compared to other malignancies, however skull metastasis is rare. Cutaneous metastasis is seen in less than 15% cases of lung cancer. These lesions are mostly detected late after the diagnosis of primary tumour in later course of disease. However, an asymptomatic patient presenting with scalp swelling as initial presentation of underlying advances lung malignancy is rare, less than 20 such cases reported in literature till date. Our case is highlighting not only the rarity of such cases but also consider detail evaluation of any scalp swelling.
Look Who's Talking
Authors: Glazer Amanda , Luo Hubert , Devgon Shivin , Wang Catherine , Yao Xintong , Yao Steven Siwei , McQuarrie Frances , Li Zelin , Palma Adalie , Wan Qinqin , Gu Warren , Sen Avi , Wang Zihui , O'Connell Grace D. , Stark Philip B.
Published: March 2023

The "job talk"is a standard element of faculty recruiting. How audiences treat candidates for faculty positions during job talks could have disparate impact on protected groups, including women. We annotated 156 job talks from five engineering and science departments for 13 categories of questions and comments. All departments were ranked in the top 10 by US News & World Report. We find that differences in the number, nature, and total duration of audience questions and comments are neither material nor statistically significant. For instance, the median difference (by gender) in the duration of questioning ranges from zero to less than two minutes in the five departments. Moreover, in some departments, candidates who were interrupted more often were more likely to be offered a position, challenging the premise that interruptions are necessarily prejudicial. These results are specific to the departments and years covered by the data, but they are broadly consistent with previous research, which found differences of comparable in magnitude. However, those studies concluded that the (small) differences were statistically significant. We present evidence that the nominal statistical significance is an artifact of using inappropriate hypothesis tests. We show that it is possible to calibrate those tests to obtain a proper P-value using randomization.