Simple epidemic models with segmentation can be better than complex ones

Given a sequence of epidemic events, can a single epidemic model capture its dynamics during the entire period? How should we divide the sequence into segments to better capture the dynamics? Throughout human history, infectious diseases (e.g., the Black Death and COVID-19) have been serious threats. Consequently, understanding and forecasting the evolving patterns of epidemic events are critical for prevention and decision making. To this end, epidemic models based on ordinary differential equations (ODEs), which effectively describe dynamic systems in many fields, have been employed. However, a single epidemic model is not enough to capture long-term dynamics of epidemic events especially when the dynamics heavily depend on external factors (e.g., lockdown and the capability to perform tests). In this work, we demonstrate that properly dividing the event sequence regarding COVID-19 (specifically, the numbers of active cases, recoveries, and deaths) into multiple segments and fitting a simple epidemic model to each segment leads to a better fit with fewer parameters than fitting a complex model to the entire sequence. Moreover, we propose a methodology for balancing the number of segments and the complexity of epidemic models, based on the Minimum Description Length principle. Our methodology is (a) Automatic: not requiring any user-defined parameters, (b) Model-agnostic: applicable to any ODE-based epidemic models, and (c) Effective: effectively describing and forecasting the spread of COVID-19 in 70 countries.

Myocardial Viability, Functional Status, and Collaterals of Patients With Chronically Occluded Coronary Arteries

Objective: Viability and functional assessments are recommended for indication and intervention for chronic coronary total occlusion (CTO). We aimed to evaluate myocardial viability and left ventricular (LV) functional status by using cardiovascular magnetic resonance (CMR) and to investigate the relationship between them and collaterals in patients with CTO.Materials and Methods: We enrolled 194 patients with one CTO artery as detected by coronary angiography. Patients were scheduled for CMR within 1 week after coronary angiography.Results: A total of 128 CTO territories (66%) showed scar based on late gadolinium enhancement (LGE) imaging. There were 1,112 segments in CTO territory, while only 198 segments (18%) subtended by the CTO artery showed transmural scar (i.e., >50% extent on LGE). Patients with viable myocardium had higher LV ejection fraction (LVEF) (56.7 ± 13.5% vs. 48.3 ± 15.4%, p < 0.001) than those with transmural scar. Angiographically, well-developed collaterals were found in 164 patients (85%). There was no significant correlation between collaterals and the presence of myocardial scar (p = 0.680) or between collaterals and LVEF (p = 0.191). Nevertheless, more segments with transmural scar were observed in patients with poorly-developed collaterals than in those with well-developed collaterals (25 vs. 17%, p = 0.010).Conclusion: Myocardial infarction detected by CMR is widespread among patients with CMO, yet only a bit of transmural myocardial scar was observed within CTO territory. Limited number of segments with transmural scar is associated with preserved LV function. Well-developed collaterals are not related to the prevalence of myocardial scar or systolic functioning, but could be related to reduce number of non-viable segments subtended by the CTO artery.

Piecewise Parabolic Approximate Computation Based on an Error-Flattened Segmenter and a Novel Quantizer

This paper proposes a novel Piecewise Parabolic Approximate Computation method for hardware function evaluation, which mainly incorporates an error-flattened segmenter and an implementation quantizer. Under a required software maximum absolute error (MAE), the segmenter adaptively selects a minimum number of parabolas to approximate the objective function. By completely imitating the circuit’s behavior before actual implementation, the quantizer calculates the minimum quantization bit width to ensure a non-redundant fixed-point hardware architecture with an MAE of 1 unit of least precision (ulp), eliminating the iterative design time for the circuits. The method causes the number of segments to reach the theoretical limit, and has great advantages in the number of segments and the size of the look-up table (LUT). To prove the superiority of the proposed method, six common functions were implemented by the proposed method under TSMC-90 nm technology. Compared to the state-of-the-art piecewise quadratic approximation methods, the proposed method has advantages in the area with roughly the same delay. Furthermore, a unified function-evaluation unit was also implemented under TSMC-90 nm technology.

Tritesia, a new substitute name for Tetrisia Walker, 1867 (Lepidoptera: Erebidae)

The genus Tetrisia (Lepidoptera, Erebidae) was established by Walker (1867b: 186) for a new species of moth from Colombia. A homographic name, however, had been proposed almost five months earlier by Walker himself (1867a: 111‒112) for a genus of shieldbugs (Heteroptera, Plataspidae) from Singapore. In neither case did Walker give an etymology for the name Tetrisia, but Waldkircher et al. (2004) have speculated that for the heteropteran genus it might allude to the unusual four-segmented antennae, as most plataspids have five antennal segments. Insterestingly, however, Walker did not mention the number of segments in his description.

Evaluating the utility of identity-by-descent segment numbers for relatedness inference via information theory and classification

Despite decades of methods development for classifying relatives in genetic studies, pairwise relatedness methods' recalls are above 90% only for first through third degree relatives. The top-performing approaches, which leverage identity-by-descent (IBD) segments, often use only kinship coefficients, while others, including ERSA, use the number of segments relatives share. To quantify the potential for using segment numbers in relatedness inference, we leveraged information theory measures to analyze exact (i.e., produced by a simulator) IBD segments from simulated relatives. Over a range of settings, we found that the mutual information between the relatives' degree of relatedness and a tuple of their kinship coefficient and segment number is on average 4.6% larger than between the degree and the kinship coefficient alone. We further evaluated IBD segment number utility by building a Bayes classifier to predict first through sixth degree relationships using different feature sets. When trained and tested with exact segments, the inclusion of segment numbers improves the recall by between 0.0028 and 0.030 for second through sixth degree relatives. However, the recalls improve by less than 0.018 per degree when using inferred segments, suggesting limitations due to IBD detection accuracy. Lastly, we compared our Bayes classifier that includes segment numbers with ERSA and IBIS and found comparable results, with the Bayes classifier and ERSA slightly outperforming each other across different degrees. Overall, this study shows that IBD segment numbers can improve relatedness inference but that errors from current SNP array-based detection methods yield dampened signals in practice.

Revision of the French Terebellidae sensu stricto (Annelida, Terebelliformia), with descriptions of nine new species

This work is the last of four papers of the Spaghetti Project, aiming to revise the species of terebellids, a.k.a. “spaghetti” worms, present in the European French waters. In this last paper the Terebellidae, sensu stricto, from French waters are revised based, on material available in the French marine stations, type materials stored in the MNHN collection and newly collected specimens. Nine new species are described using both morphological and molecular tools: Eupolymnia gili n. sp., E. lacazei n. sp., E. meissnerae n. sp., Lanice kellyslateri n. sp., Paramphitrite dragovabeci n. sp., Pista labruneae n. sp., P. miosseci n. sp., P. sauriaui n. sp., and Terebella banksyi n. sp. European species of Eupolymnia are distinguished mainly by the shape of the lateral lobes and the size of the branchial stems. The two species belonging to Lanice genus are distinguished by the fusion of the first ventral shields, the shape of both noto- and neuropodia, and the pigmentation of the upper lip. The two species of Paramphitrite are distinguished by the presence or absence of a medial dorsal gap between the pairs of branchiae, by the shape of the lateral lobes and the presence or absence of a nephridial papilla on segment 4. The different species of Pista are distinguished by the number of pairs of branchiae, the shape of the lateral lobes and uncini. Finally, the two species of Terebella are distinguished by the number of segments with nephridial and genital papillae and the segments on which the branchiae occur. An identification key for European species of Terebellidae sensu stricto is also provided.

ABOUT REGENERATION OF ALIEN POLYCHAETE POLYDORA WEBSTERI (ANNELIDA: SPIONIDAE)

New data on the regenerative capacity of the invader polychaete Polydora websteri Hartman in Loosanoff & Engle, 1943 have been obtained. The material was collected in 2019-2020 in the area of Sevastopol. Polychaetes were extracted from blisters in the valves of an exotic oyster species for the Black Sea - Crassostrea gigas (Thunberg, 1793). Molluscs were grown on an oyster farm. Polychaetes were kept in aquariums with filtered seawater at a temperature from 8.8 to 25.8 °C and a salinity of 17.5-17.8‰. Under laboratory conditions, body segments were removed from the worms and their recovery was observed. It was found that P. websteri regenerated both the anterior and posterior parts of the body. The minimum number of segments capable to simultaneously restore both anterior and posterior regions is three mid-body segments. The regeneration process in P. websteri depends significantly on the water temperature. In the range of 8.8-26 °С, a direct relationship was established between the water temperature and the number of regenerated individuals. An inverse relationship was found between the water temperature and the time spent on regenerating the lost fragments. When warming up the water, the proportion of regenerated P. websteri increased from 15 to 87%, and the duration of regeneration decreased 2.5 times.

Severe Radiological Manifestation in Patients with Diabetes and Pulmonary Tuberculosis: A Cross-sectional Study

Purpose: Diabetes mellitus (DM) is believed to affect tuberculosis (TB) at multiple levels in disease control and treatment efficacy, but clinical and radiological presentation resulting from interaction of the two diseases is not known. We conducted a retrospective study to investigate how glycemic control impacts radiological and clinical manifestations in TB patients. Methods: A cross-sectional study was conducted on data obtained from medical records of 438 patients confirmed with TB-DM comorbidity at The Third people’s hospital of Shenzhen from April 1, 2014 to April 30, 2019. Their CT images were reviewed, and patients were divided into subgroups according to lung cavitation: with and without cavities, and number of segments showing pulmonary infiltration: <4 segment, 4-8 segment, >8 segment infiltrates. We then compared clinical parameters between these groups. Results: The median age of the patients was 50.0 years (IQR 43.3-56) and 86% (n=375) of them were male. Pulmonary cavities were found in 80.8% patients. 42.7% and 27.2% patients were seen to have infiltration involving 4-8 and >8 lung segments respectively. Patients presented with cavitation and infiltration involving a greater number of lung segments had significantly higher values of WBC, MONO%, GRA%, CRP, lower LYN% level and higher bacterial burden in sputum (P<0.001). Higher HbA1c and FBG were only observed in patients with lung cavities (P<0.001). There was no difference in positive ELISPOT.TB and PCT level between the groups regardless of presence or absence of lung cavity (P>0.9 and P=0.1 respectively). Lower HGB, ALB and higher PCT were observed in patients with infiltration involving more lung segments.Conclusion: Hyper-inflammation in peripheral blood was significantly associated with cavity and the number of lung lesions. Hyperglycemia was significantly associated with the development of lung cavity. Glycemic control and inflammation influenced radiographic manifestations in patients with TB-DM.

A Modified Calculation Improves the Accuracy of Predicted Postoperative Lung Function Values in Lung Cancer Patients

Purpose Preoperative pulmonary function testing is mandatory for non-small cell lung cancer (NSCLC) surgery. The predicted postoperative FEV1 (ppoFEV1) is used for further risk stratification. We compared the ppoFEV1 with the postoperative FEV1 (postFEV1) in order to improve the calculation of the ppoFEV1. Methods 87 patients voluntarily received an FEV1 assessment 1 year after surgery. ppoFEV1 was calculated according to the Brunelli calculation. Baseline characteristics and surgical procedure were compared in a uni- and multivariate analysis between different accuracy levels of the ppoFEV1. Parameters which remained significant in the multinominal regression analysis were evaluated for a modification of the ppoFEV1 calculation. Results Independent factors for a more inaccurate ppoFEV1 were preoperative active smoking (odds ratio (OR) 4.1, confidence interval (CI) 3.6–6.41; p = 0.01), packyears (OR 4.1, CI 3.6–6.41; p = 0.008), younger age (OR 1.1, CI 1.01–1.12; p = 0.03), and patients undergoing pneumectomy (OR 5.55, CI 1.35–23.6; p = 0.01). For the customized ppoFEV1 we excluded pneumonectomies. For patients < 60 years, an additional lung segment was added to the calculation. ppoFEV1 = preFEV1 × $$1-\left(\frac{\text{Lung segments resected} + 1}{\text{Total number of segments}}\right)$$ 1 - Lung segments resected + 1 Total number of segments . For actively smoking patients with more than 30 packyears we subtracted one lung segment from the calculation ppoFEV1 = PreFEV1 × $$1-\left(\frac{\text{Lung segments resected} - 1}{\text{Total number of segments}}\right)$$ 1 - Lung segments resected - 1 Total number of segments . Conclusion We were able to enhance the predictability of the ppoFEV1 with modifications. The modified ppoFEV1 (1.828 l ± 0.479 l) closely approximates the postFEV1 of 1.823 l ± 0.476 l, (0.27%) while the original ppoFEV1 calculation is at 1.78 l ± 0.53 (2.19%). However, if patients require pneumectomy, more complex techniques to determine the ppoFEV1 should be included to stratify risk.