bluuebunny/crossref_metadata_2025 huggingface dataset:
Revisiting the minimum-norm problem
Authors: Moreno-Pulido Soledad , Sánchez-Alzola Alberto , García-Pacheco Francisco Javier
Published: February 2022

The design of optimal Magnetic Resonance Imaging (MRI) coils is modeled as a minimum-norm problem (MNP), that is, as an optimization problem of the form $\min_{x\in\mathcal{R}}\|x\|$

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Boundedness and compactness of a class of integral operators with power and logarithmic singularity when $p\leq q$
Authors: Abylayeva Akbota , Oinarov Ryskul , Seilbekov Bolat
Published: February 2022

In this paper, necessary and sufficient conditions for the boundedness and compactness of one class of integral operators with power and logarithmic singularities in weighted Lebesgue spaces are obtained.
Convergence analysis of a novel iteration process with application to a fractional differential equation
Authors: Uddin Izhar , Garodia Chanchal , Abdeljawad Thabet , Mlaiki Nabil
Published: February 2022

The objective of this article is to study a three-step iteration process in the framework of Banach spaces and to obtain convergence results for Suzuki generalized nonexpansive mappings. We also provide numerical examples that support our main results and illustrate the convergence behavior of the proposed process. Further, we present a data-dependence result that is also supported by a nontrivial numerical example. Finally, we discuss the solution of a nonlinear fractional differential equation by utilizing our results.
Assessing negative core beliefs in eating disorders: revision of the Eating Disorder Core Beliefs Questionnaire
Authors: Hatoum Amaani H. , Burton Amy L. , Abbott Maree J.
Published: February 2022

Background

Increased theoretical and empirical attention has been given to examining the role of core beliefs in both the development and maintenance of eating disorders (EDs). The Eating Disorder Core Beliefs Questionnaire (ED-CBQ) is self-report measure designed to assess five dimensions of core beliefs relating to eating disorders; self-loathing, unassertive/inhibited, demanding/needing help and support, abandoned/deprived, and high standards for the self. The present study aimed to evaluate the psychometric properties of the ED-CBQ and to develop a revised and improved version of the original measure after evaluating its factor structure and related properties.

Methods

A sample of undergraduate university students (N = 763) completed an online test battery of questionnaires. Putative ED-symptomatic (n = 384) and non-ED (n = 379) subgroups were created from self-reported responses from the Eating Disorder Examination Questionnaire (EDEQ). Confirmatory factor analyses (CFAs) were performed, and internal consistency, construct validity, group differences and clinical utility was examined.

Results

An initial CFA did not support the original five-factor 40-item ED-CBQ. A revised version was developed that possessed equal or superior psychometric properties to the original 40-item measure. The ED-CBQ-R demonstrated superior model fit, similar levels of reliability and construct validity, and the ability to discriminate between putative ED diagnostic groups.

Conclusions

Our results suggest that the ED-CBQ-R is a valid, reliable, but more importantly an efficient and accessible measure with the potential to be utilised both clinically and in research settings.
Optimizing the thermal treatment for restoration of brittle archaeological silver artifacts
Authors: Liu Shengyu , Li Zhuopeng , Zhou Yihang , Li Ruixuan , Xie Zhenda , Liu Chudong , Hu Gang , Hu Dongbo
Published: February 2022

Archaeological silver artifacts are often found to be brittle because of long-term corrosion. However, the restoration of brittle archaeological silver artifacts by thermal treatment has never been quantitatively and systematically studied due to the lack of sufficient experimental samples. Herein, the simulated Ag–Cu alloy flake samples with intergranular corrosion consistent with those brittle archaeological silver artifacts were prepared through two-step annealing and accelerated aging in Fe(NO3)3 + AgNO3 solution. The changes in the microstructure and mechanical strength (σbb, Eb, and HV) of the brittle samples after thermal treatments were studied with the help of SEM–EDS, metallographic observation, three-point bending tests, and microhardness tests. In addition, the most suitable conditions for the restoration of the brittle samples were summarized by the temperature–time (T-t) map obtained from a series of comprehensive thermal treatments. Moreover, the differences in microstructures and mechanical strength between the brittle samples annealed in an aerobic/anaerobic environment were revealed. This work provides an important reference for the restoration and conservation of brittle archaeological silver artifacts.
Poisson logit hurdle model with associated factors of perinatal mortality in Ethiopia
Authors: Aragaw Abiba Mihret , Azene Abebaw Gedef , Workie Mekuanint Simeneh
Published: February 2022

Perinatal mortality is the total number of fetal death and early neonatal death. Perinatal mortality is a major public health problem, particularly in developing countries, and is used as an implication of the economic, social, and health status of the country. The analysis of count data with hurdle and zero-inflated count models are the most applicable methods to accommodate with excessive zero counts. Therefore, this study aimed to apply the Poisson logit hurdle model to identify the associated factors of perinatal mortality in Ethiopia. A cross-sectional study design was conducted in Ethiopia using EDHS 2016. The sample was multistage stratified and units selected in a two-stage cluster sampling design. The association between the outcome and the independent variables was determined using the Poisson logit hurdle model. A total of 7230 mothers were obtained from EDHS 2016 survey. Of these mothers, 95.27% of them never, 4.47% of them once, 0.26% twice, and 0.04% three times experienced perinatal mortality preceding 5 years of the survey. The main protective associated factors were 40–49 years age of mother, having long preceding birth interval, and secondary + husband education. Parity is greater than four, rural residence, Caesarean section delivery, multiple pregnancies, institutional delivery, having a history of abortion were increased perinatal mortality per mother. This study implies that intervention is needed on family planning and mode of delivery to minimize perinatal mortality in the country.
Patients with chronic Achilles tendon rupture have persistent limitations in patient-reported function and calf muscle function one year after surgical treatment – a case series
Authors: Nordenholm Anna , Nilsson Niklas , Senorski Eric Hamrin , Helander Katarina Nilsson , Westin Olof , Olsson Nicklas
Published: February 2022

Purpose

Evaluate the one-year postoperative outcomes in patients with Chronic Achilles tendon rupture.

Methods

Patients surgically treated for Chronic Achilles tendon rupture (n = 22, 14 males and 8 females, mean age 61 ± 15) were evaluated by Achilles tendon Total Rupture Score, The Physical Activity Scale, The Foot and Ankle Outcome Score, Calf muscle endurance test, counter movement jump, Hopping, ultrasound measurement of tendon length, Achilles Tendon Resting Angle, dorsi flexion range of motion and calf muscle circumference. Muscle function and tendon length outcomes on the injured side were compared with the healthy side.

Results

The patients scored a mean of 62 ± 26 on the Achilles tendon Total Rupture Score. Median scores on the injured compared with the healthy side were lower in heel-rise repetitions (20 vs 24 cm, p = 0.004), hel-rise height (8 vs 10 cm, p < 0.001), heel-rise total work (872 vs 1590 joule, p < 0.001) and hopping ratio (0.37 vs 0.48, p = 0.005). Median calf circumference was smaller (37 vs 38 cm, p = 0.001) and the mean tendon elongation greater on the injured side; Achilles tendon resting angle (55 vs 50°, p < 0.001) and ultrasound (22.4 vs 20.5 cm, p = 0.006).

Conclusions

At one year postoperatively, patients with chronic Achilles tendon rupture reported persistent limitations in subjective foot and ankle function. Heel-rise height and total work as well as hopping ratio were not recovered, and there was an elongation of the injured Achilles tendon compared with the healthy tendon.

Level of evidence

IV
Diagnosing ventilator-associated pneumonia (VAP) in UK NHS ICUs: the perceived value and role of a novel optical technology
Authors: Jones W. S. , Suklan J. , Winter A. , Green K. , Craven T. , Bruce A. , Mair J. , Dhaliwal K. , Walsh T. , Simpson A. J. , Graziadio S. , Allen A. J.
Published: February 2022

Background

Diagnosing ventilator-associated pneumonia (VAP) in an intensive care unit (ICU) is a complex process. Our aim was to collect, evaluate and represent the information relating to current clinical practice for the diagnosis of VAP in UK NHS ICUs, and to explore the potential value and role of a novel diagnostic for VAP, which uses optical molecular alveoscopy to visualise the alveolar space.

Methods

Qualitative study performing semi-structured interviews with clinical experts. Interviews were recorded, transcribed, and thematically analysed. A flow diagram of the VAP patient pathway was elicited and validated with the expert interviewees. Fourteen clinicians were interviewed from a range of UK NHS hospitals: 12 ICU consultants, 1 professor of respiratory medicine and 1 professor of critical care.

Results

Five themes were identified, relating to [1] current practice for the diagnosis of VAP, [2] current clinical need in VAP diagnostics, [3] the potential value and role of the technology, [4] the barriers to adoption and [5] the evidence requirements for the technology, to help facilitate a successful adoption. These themes indicated that diagnosis of VAP is extremely difficult, as is the decision to stop antibiotic treatment. The analysis revealed that there is a clinical need for a diagnostic that provides an accurate and timely diagnosis of the causative pathogen, without the long delays associated with return of culture results, and which is not dangerous to the patient. It was determined that the technology would satisfy important aspects of this clinical need for diagnosing VAP (and pneumonia, more generally), but would require further evidence on safety and efficacy in the patient population to facilitate adoption.

Conclusions

Care pathway analysis performed in this study was deemed accurate and representative of current practice for diagnosing VAP in a UK ICU as determined by relevant clinical experts, and explored the value and role of a novel diagnostic, which uses optical technology, and could streamline the diagnostic pathway for VAP and other pneumonias.
COVID-19-associated mucormycosis: an update of anesthetic management
Authors: Solanki Nilesh Maganbhai , Solanki Rekha Nilesh , Madaliya Arun Vrajlal , Jasoliya Rasmita Haresh , Upadhyay Dhara Tushar
Published: February 2022

Background

Mucormycosis is uncommon, progressive fungal infection with mortality rate on higher side. The anesthetic management of surgical debridement in mucormycosis is challenging.

We evaluated the anesthetic management of mucormycosis patients associated with problems of airway management, predisposing factors, and adverse effect of antifungal therapy who underwent surgical resection of necrotized tissues.

Results

Fifty-six patients presented with uncontrolled diabetes mellitus. All patients had history of COVID-19 infection and received steroid during treatment. Nasal endoscopic debridement was done in 43 patients, total maxillectomy in 14 patients. Temporalis flap was needed in five patients, and orbital exenteration was required in three patients. Central venous catheter was inserted in 17 patients, and invasive arterial monitoring was done in ten patients. All patients administered lyophilized amphotericin B (deoxycholate) in combination with surgical debridement.

Thirteen patients were shifted to ICU for further management and continuous hemodynamic monitoring. Fifteen patients were expired, and the mortality rate was 26.31%.

Conclusions

Challenges include difficult intubation and renal function impairment due to prolonged antifungal therapy. Postoperative ICU management is important in mucormycosis patients due to comorbidities and rapid progressive infection after surgery.
Cannabis and schizophrenia: characterisation of a risk factor in a sample of Moroccan patients hospitalised for psychosis
Authors: Ouanouche El Hassan , Elmostafi Hicham , Amarat Naoufal , Wafaa Ouahid , Ryad Tamouza , El Hessni Aboubaker , Mesfioui Abdelhalem
Published: February 2022

Background

In addition to the biological plausibility widely described through a very large number of studies, the causal link between cannabis uses and schizophrenia disorders has become illicit internationally and given the scarcity of similar studies in Morocco. Our study consists of a prospective descriptive study in the psychiatric department of the Moulay ben Abdallah Hospital in Essaouira. The sample consisted of 95 patients diagnosed with schizophrenia according to the DSM5 criteria. The diagnostic assessment included the Positive and Negative Syndrome Scale to assess the severity of positive and negative symptoms of schizophrenia as well as the patient’s general psychopathology, the Clinician-Rated Dimensions of Psychosis Symptom Severity to assess the symptom severity of the psychotic dimensions according, and the Cannabis Abuse Screening Test to assess the extent of cannabis use.

Results

The mean age of the patients recruited in the study was 33.7 ± 9.37 years with a clear male predominance (p < 0.0001). Cannabis users compared to non-users were younger and comprised only men. Cannabis users also have a lower educational and economic level than non-users. Furthermore, a clear dose effect of cannabis uses on the onset of positive and negative symptoms of schizophrenia. The temporality criterion is clear in our study, since the predictivity of the parameter: “age of onset of cannabis use” is highly significant (p = 0.000). These results suggest that cannabis use can be considered as the most illicit risk factor for the development and/or onset of schizophrenia.

Conclusions

These results suggest that there is a causal relationship between cannabis use and/or dependence (problematic use) and the onset and/or worsening of schizophrenic disorder. This means that problematic cannabis use can be considered as a real risk factor for the emergence and development of schizophrenic disorder.
Converging IoT protocols for the data integration of automation systems in the electrical industry
Authors: Gil Santiago , Zapata-Madrigal Germán D. , García-Sierra Rodolfo , Cruz Salazar Luis Alberto
Published: February 2022

The Internet of Things (IoT) plays an important role in the development of applications for the Electrical Industry. The data has become essential for the technological advances in this industry, changing abruptly due to the distributed energy resources and the smart grid concept. The data integration also represents a relevant matter to address when performing IoT projects for electrical industry applications. The electrical industry requires incorporating different IoT protocols to comply with the distinct scenarios and the interoperability. This work proposes integrating the HTTP REST, MQTT, LoRaWAN, and OPC UA open communications protocols into an IoT platform and interoperable architecture for smart grid applications. This approach intends to contribute to smart grid solutions and automation systems in the electrical industry, promotes further integration of communication protocols for this field, and enables additional data-based applications for their automation systems. A Multi-Agent System architecture based on the IoT integration is proposed as an application to show how implementable is this approach in current and technological electrical systems.
Intracavity spherical aberration for selective generation of single-transverse-mode Laguerre-Gaussian output with order up to 95
Authors: Sheng Quan , Wang Aihua , Ma Yuanyuan , Wang Sijia , Wang Meng , Shi Zheng , Liu Junjie , Fu Shijie , Shi Wei , Yao Jianquan , Omatsu Takashige
Published: February 2022

We investigate the generation of single-transverse-mode Laguerre-Gaussian (LG) emission from a diode-end-pumped Nd:YVO4, 1064 nm laser using mode selection via intracavity spherical aberration (SA). We present both theoretical and experimental investigations, examining the limits of the order (both radial and angular indices) of the LG modes which can be produced, along with the resultant output power. We found that in order to generate single-mode emission of low-order LG modes which have relatively small beam diameters, lenses with shorter focal-length were required (to better differentiate neighboring LG modes via SA). The converse was true of LG modes with high-order. Through appropriate choice of the focal length of the intracavity lens, we were able to generate single-mode, LG0,±m laser output with angular indices m selectable from 1 to 95, as well as those with non-zero radial indices p of up to 4.
Long-term survival rates of patients with nasopharyngeal carcinoma treated by radiochemotherapy: a retrospective cohort study
Authors: Kazemian Ali , Ghalehtaki Reza , Farazmand Borna , Taherioun Maryam , Razmkhah Mahdieh , Khalili Nastaran , Farhan Farshid , Aghili Mahdi , Esmati Ebrahim
Published: February 2022

Background

Nasopharyngeal cancer (NPC) is showing an increasing incidence in Iran. Radiation is the main treatment of this cancer. Use of new techniques such as intensity-modulated radiotherapy (IMRT) is on the rise. Here, we aimed to evaluate the oncological outcomes of NPC patients treated with three-dimensional conformal radiotherapy (3DCRT) for a more reliable comparison with IMRT in the future.

Results

We reviewed the medical records of 106 patients with NPC treated by definitive radiotherapy from 2007 to 2016. Patients were treated with 70 Gy in 2-Gy fractions. Twenty-one patients died during the follow-up period. Twenty-nine patients suffered from locoregional or distant recurrences. Of these, 6 recurred after 2 years of treatment completion. The 2-year and 5-year overall survival rates were 81% and 76%, respectively. The 2-year and 5-year progression-free survival rates were 72% and 63%, respectively. The 5-year locoregional recurrence and distant metastasis-free survival rates were 68% and 69%, respectively.

Conclusion

Due to high survival rates of NPC and the importance of receiving planned total dose of RT, the treatment-related toxicity and quality of life are critical considerations both for patients during active treatment and for survivors.
Effective medium modeling of the joint elastic-electrical properties of sandstones with partial water saturation
Authors: Han Tongcheng , Yan Han , Fu Li-Yun , Xu Denghui
Published: February 2022

Quantitatively assessing fluid saturation in reservoir rocks has been the ultimate goal of hydrocarbon geophysical investigations. Joint interpretation of acoustic and electromagnetic survey data indicates a promise to improve the fluid quantification ability. However, the saturation effects on the cross-property relationship between the elastic and electrical rock properties (i.e., the joint elastic-electrical properties) that form the key to the successful joint interpretation remain poorly understood. We have developed an effective medium modeling scheme for the joint elastic-electrical properties of sandstones with partial water saturation and studied theoretically the effects of porosity and grain and pore geometries on the saturation-dependent joint elastic-electrical properties of sandstones. Comparison between the modeling results and an available laboratory data set confirms the applicability of the approach for modeling the joint elastic-electrical properties of partially saturated sandstones. P-wave velocity is found to decrease with increasing electrical conductivity as water saturation increases in rocks with low porosity, low grain aspect ratio, and high pore aspect ratio. The water saturation effects on the joint properties are amplified in rocks with higher porosity, greater grain aspect ratio, and lower pore aspect ratio, in which P-wave velocity indicates an asymmetric V-shaped relationship with electrical conductivity as an implicit function of increasing water saturation. It also is found that the increasing porosity affects the joint properties in a gradually increasing manner, whereas the increasing grain and pore aspect ratios impose a decreasing impact on the joint elastic-electrical correlations. The results have strengthened our understanding of the joint elastic-electrical properties of partially saturated sandstones and will facilitate the joint interpretation of acoustic and electromagnetic survey data for improved fluid quantification.
Data-driven modeling of time-domain induced polarization
Authors: Bérubé Charles L. , Bérubé Pierre
Published: February 2022

Induced polarization (IP) measurements are affected by various types of noise, which should be removed prior to data interpretation. However, existing data processing methods often rely on empirical assumptions about the standard shape of IP decay curves. Our goal is to introduce a data-driven approach for modeling and processing time-domain IP measurements. To reach this goal, we train a variational autoencoder (VAE) on 1,600,319 IP decays collected in Canada, the United States, and Kazakhstan. The proposed deep learning approach is unsupervised and avoids the pitfalls of IP parameterization with empirical Cole-Cole and Debye decomposition models, simple power-law models, or mechanistic models. Four applications of VAEs are key to modeling and processing IP data: (1) synthetic data generation, (2) Bayesian denoising, (3) evaluation of signal-to-noise ratio, and (4) outlier detection. Furthermore, we interpret the IP data compilation’s latent representation and reveal a correlation between its first dimension and the average chargeability. Finally, we determine that a single real-valued scalar parameter contains sufficient information to encode IP data. This new finding suggests that modeling time-domain IP data using mathematical models governed by more than one free parameter is ambiguous, whereas modeling only the average chargeability is justified. A pretrained implementation of the VAE model is available as open-source Python code.
Dynamical scaling of Loschmidt echo in non-Hermitian systems
Authors: Tang Jia-Chen , Kou Su-Peng , Sun Gaoyong
Published: February 2022

We show that non-Hermitian biorthogonal many-body phase transitions can be characterized by the enhanced decay of Loschmidt echo. The quantum criticality is numerically investigated in a non-Hermitian transverse field Ising model by performing the finite-size dynamical scaling of Loschmidt echo. We determine the equilibrium correlation length critical exponents that are consistent with previous results from the exact diagonalization. More importantly, we introduce a simple method to detect quantum phase transitions with the short-time average of rate function motivated by the critically enhanced decay behavior of Loschmidt echo. Our studies show how to detect equilibrium many-body phase transitions with biorthogonal Loschmidt echo that can be observed in future experiments via quantum dynamics after a quench.
Fat Mass Has Negative Effects on Bone, Especially in Men: A Cross-sectional Analysis of NHANES 2011-2018
Authors: Jain Rajesh K , Vokes Tamara
Published: February 2022

Context

The effect of high levels of obesity on bone health are not clear.

Objective

We aimed to examine the associations of body composition and bone mineral density (BMD) in a large, nationally representative population with a wide range of body mass index.

Methods

We analyzed 10 814 subjects aged 20-59 from NHANES 2011-2018 who had total body BMD and body composition data. Body composition was examined as lean mass index (LMI) and fat mass index (FMI). Linear regression models were created with BMD as the outcome, while examining LMI and FMI and controlling for age, gender, race/ethnicity, height, and smoking status.

Results

In multivariable modeling, every 1 kg/m2 additional LMI was associated with 0.19 higher T-score, while every additional 1 kg/m2 in FMI was associated with 0.10 lower T-score (P < .001 for both). The negative association of FMI with BMD was mainly seen when adjusting for LMI. Effects of LMI were similar in men and women, but the effect of FMI was more negative in men (0.13 lower T-score per additional 1 kg/m2 of FMI in men vs 0.08 lower BMD T-score in women, P for interaction < .001).

Conclusion

In subjects under 60 years old, lean mass had a strong positive association with BMD. Conversely, fat mass had a moderate, negative association with BMD that was most notable in men at high levels of fat. Our results emphasize the importance of bone health in obesity and may explain site-specific increases in fracture rates in some studies of obese subjects.
The Ghazal as “World Poetry”: Between Worlding and Vernacularization
Authors: Grewal Sara Hakeem
Published: February 2022

While the ghazal has appeared in many linguistic traditions, its diversity is undermined by the imposition of a singular definition of this genre, which is further compounded by the overly simplistic identification of ghazal as lyric; these lyricized readings of the ghazal as both transhistorical and transnational rely on a discourse of “worlding” as an imperial project of cultural recovery and homogenization. In contrast, this article employs the methodology of historical poetics to argue via a reading of meta-ghazals in Persian, Urdu, and English that reading practices around the ghazal—including definitions of the genre that variously emphasize form versus theme—change according to the historical and geographical context of its circulation. However, by celebrating the ghazal’s travel as seemingly apolitical and/or ahistorical, the discourse of world poetry, particularly in the reception of the ghazals of Agha Shahid Ali, participates in an ongoing imperialism in world literary study. In contrast, we can read the ghazals of Adrienne Rich as exemplifying the tradition of vernacularization that has enabled the ghazal’s movement between languages, such that her work, like the work of historical poetics as a methodology, honors the history of the form’s travel through its appearance in contemporary American English.
Feeling Meter
Authors: Kozak Mariusz
Published: February 2022

This article explores the nature of metrical knowledge underlying Justin London's many-meters hypothesis. It argues that meter is a form of culturally situated kinesthetic knowledge, or a knowledge of what it feels like to move to music in a particular way. This reframing of meter focuses on its technical and bodily dimensions, which links the analysis of meter with issues of social inclusion and exclusion, of learning and unlearning, and of habit and novelty. The article illustrates the implications of this approach with examples from recent progressive metal, where musicians manipulate the backbeat to present listeners with affordances for the enactment of different forms of time.
An Intervallic Approach to Sixteenth-Century Chromaticism
Authors: Turci-Escobar John
Published: February 2022

This article proposes an intervallic approach to classifying and interpreting sixteenth-century chromaticism. The approach is based on a distinction between active leading tones, which imply resolution by diatonic semitone, and stable notes, which do not. This distinction underlies a dyadic approach to categorizing contrapuntal uses of chromatic semitones, providing an alternative to prevalent classifications by interval of triadic root or bass motion. The article distinguishes three chromatic semitone types: (1) normative/expressive, (2) chromatically deflected leading tones, and (3) chromatically thwarted leading tones. For each type, the article discusses representative examples drawn from motets and madrigals by Orlando di Lasso, Giaches de Wert, Luca Marenzio, Luzzasco Luzzaschi, Alfonso Fontanelli, and Carlo Gesualdo, and considers how the chromatic semitones express the poetic texts.
The Nasonia pair-rule gene regulatory network retains its function over 300 million years of evolution
Authors: Taylor Shannon E. , Dearden Peter K.
Published: February 2022

Insect segmentation is a well-studied and tractable system with which to investigate the genetic regulation of development. Though insects segment their germband using a variety of methods, modelling work implies that a single gene regulatory network can underpin the two main types of insect segmentation. This means limited genetic changes are required to explain significant differences in segmentation mode between different insects. This idea needs to be tested in a wider variety of species, and the nature of the gene regulatory network (GRN) underlying this model has not been tested. Some insects, e.g. Nasonia vitripennis and Apis mellifera segment progressively, a pattern not examined in previous studies of this segmentation model, producing stripes at different times progressively through the embryo, but not from a segment addition zone. Here, we aim to understand the GRNs patterning Nasonia using a simulation-based approach. We found that an existing model of Drosophila segmentation ( Clark, 2017) can be used to recapitulate the progressive segmentation of Nasonia, if provided with altered inputs in the form of expression of the timer genes Nv-caudal and Nv-odd paired. We predict limited topological changes to the pair-rule network and show, by RNAi knockdown, that Nv-odd paired is required for morphological segmentation. Together this implies that very limited changes to the Drosophila network are required to simulate Nasonia segmentation, despite significant differences in segmentation modes, implying that Nasonia use a very similar version of an ancestral GRN used by Drosophila, which must therefore have been conserved for at least 300 million years.
Hedgehog pathway modulation by glypican 3-conjugated heparan sulfate
Authors: Liu Yulu Cherry , Wierbowski Bradley M. , Salic Adrian
Published: February 2022

Glypicans are a family of cell surface heparan sulfate proteoglycans that play critical roles in multiple cell signaling pathways. Glypicans consist of a globular core, an unstructured stalk modified with sulfated glycosaminoglycan chains, and a glycosylphosphatidylinositol anchor. Though these structural features are conserved, their individual contribution to glypican function remains obscure. Here, we investigate how glypican 3 (GPC3), which is mutated in Simpson–Golabi–Behmel tissue overgrowth syndrome, regulates Hedgehog signaling. We find that GPC3 is necessary for the Hedgehog response, surprisingly controlling a downstream signal transduction step. Purified GPC3 ectodomain rescues signaling when artificially recruited to the surface of GPC3-deficient cells but has dominant-negative activity when unattached. Strikingly, the purified stalk, modified with heparan sulfate but not chondroitin sulfate, is necessary and sufficient for activity. Our results demonstrate a novel function for GPC3-associated heparan sulfate and provide a framework for the functional dissection of glycosaminoglycans by in vivo biochemical complementation.

This article has an associated First Person interview with the first author of the paper.
Energy expenditure does not solely explain step length–width choices during walking
Authors: Antos Stephen A. , Kording Konrad P. , Gordon Keith E.
Published: February 2022

Healthy young adults have a most preferred walking speed, step length and step width that are close to energetically optimal. However, people can choose to walk with a multitude of different step lengths and widths, which can vary in both energy expenditure and preference. Here, we further investigated step length–width preferences and their relationship to energy expenditure. In line with a growing body of research, we hypothesized that people's preferred stepping patterns would not be fully explained by metabolic energy expenditure. To test this hypothesis, we used a two-alternative forced-choice paradigm. Fifteen participants walked on an oversized treadmill. Each trial, participants performed two prescribed stepping patterns and then chose the pattern they preferred. Over time, we adapted the choices such that there was 50% chance of choosing one pattern over another (equally preferred). If people's preferences are based solely on metabolic energy expenditure, then these equally preferred stepping patterns should have equal energy expenditure. In contrast, we found that energy expenditure differed across equally preferred step length–width patterns (P<0.001). On average, longer steps with higher energy expenditure were preferred over shorter and wider steps with lower energy expenditure (P<0.001). We also asked participants to rank a set of shorter, wider and longer steps from most preferred to least preferred, and from most energy expended to least energy expended. Only 7/15 participants had the same rankings for their preferences and perceived energy expenditure. Our results suggest that energy expenditure is not the only factor influencing a person's conscious gait choices.
Active tactile exploration and tactually induced turning in tethered walking stick insects
Authors: Berendes Volker , Dürr Volker
Published: February 2022

Many animals use their tactile sense for active exploration and tactually guided behaviors such as near-range orientation. In insects, tactile sensing is often intimately linked to locomotion, resulting in the orchestration of several concurrent active movements, including turning of the entire body, rotation of the head, and searching or sampling movements of the antennae. The present study aims at linking the sequence of tactile contact events to associated changes of all three kinds of these active movements (body, head and antennae). To do so, we chose the Indian stick insect Carausius morosus, an organism commonly used to study sensory control of locomotion. Methodologically, we combined recordings of walking speed, heading, whole-body kinematics and antennal contact sequences during stationary, tethered walking and controlled presentation of an ‘artificial twig’ for tactile exploration. Our results show that object presentation episodes as brief as 5 s are sufficient to allow for a systematic investigation of tactually induced turning behavior in walking stick insects. Animals began antennating the artificial twig within 0.5 s, and altered the beating fields of both antennae in a position-dependent manner. This change was mainly carried by a systematic shift of the head–scape joint movement and accompanied by associated changes in contact likelihood, contact location and sampling direction of the antennae. The turning tendency of the insect also depended on stimulus position, whereas the active, rhythmic head rotation remained unaffected by stimulus presentation. We conclude that the azimuth of contact location is a key parameter of active tactile exploration and tactually induced turning in stick insects.
Recognition of natural objects in the archerfish
Authors: Volotsky Svetlana , Ben-Shahar Ohad , Donchin Opher , Segev Ronen
Published: February 2022

Recognition of individual objects and their categorization is a complex computational task. Nevertheless, visual systems can perform this task in a rapid and accurate manner. Humans and other animals can efficiently recognize objects despite countless variations in their projection on the retina due to different viewing angles, distance, illumination conditions and other parameters. To gain a better understanding of the recognition process in teleosts, we explored it in archerfish, a species that hunts by shooting a jet of water at aerial targets and thus can benefit from ecologically relevant recognition of natural objects. We found that archerfish not only can categorize objects into relevant classes but also can do so for novel objects, and additionally they can recognize an individual object presented under different conditions. To understand the mechanisms underlying this capability, we developed a computational model based on object features and a machine learning classifier. The analysis of the model revealed that a small number of features was sufficient for categorization, and the fish were more sensitive to object contours than textures. We tested these predictions in additional behavioral experiments and validated them. Our findings suggest the existence of a complex visual process in the archerfish visual system that enables object recognition and categorization.
The Impact of Surveillance Imaging Frequency on the Detection of Distant Disease for Patients with Resected Stage III Melanoma
Authors: Dieng Mbathio , Lord Sarah J. , Turner Robin M. , Nieweg Omgo E. , Menzies Alexander M. , Saw Robyn P. M. , Einstein Andrew J. , Emmett Louise , Thompson John F. , Lo Serigne N. , Morton Rachael L.
Published: February 2022

Background

It is not known whether there is a survival benefit associated with more frequent surveillance imaging in patients with resected American Joint Committee on Cancer stage III melanoma.

Objective

The aim of this study was to investigate distant disease-free survival (DDFS), melanoma-specific survival (MSS), post distant recurrence MSS (dMSS), and overall survival for patients with resected stage III melanoma undergoing regular computed tomography (CT) or positron emission tomography (PET)/CT surveillance imaging at different intervals.

Patients and Methods

A closely followed longitudinal cohort of patients with resected stage IIIA–D disease treated at a tertiary referral center underwent 3- to 4-monthly, 6-monthly, or 12-monthly surveillance imaging between 2000 and 2017. Survival outcomes were estimated using the Kaplan–Meier method, and log-rank tests assessed the significance of survival differences between imaging frequency groups.

Results

Of 473 patients (IIIA, 19%; IIIB, 31%; IIIC, 49%; IIID, 1%) 30% underwent 3- to 4-monthly imaging, 10% underwent 6-monthly imaging, and 60% underwent 12-monthly imaging. After a median follow-up of 6.2 years, distant recurrence was recorded in 252 patients (53%), with 40% detected by surveillance CT or PET/CT, 43% detected clinically, and 17% with another imaging modality. Median DDFS was 5.1 years (95% confidence interval 3.9–6.6). Among 139 IIIC patients who developed distant disease, the median dMSS was 4.4 months shorter in those who underwent 3- to 4-monthly imaging than those who underwent 12-monthly imaging.

Conclusion

Selecting patients at higher risk of distant recurrence for more frequent surveillance imaging yields a higher proportion of imaging-detected distant recurrences but is not associated with improved survival. A randomized comparison of low versus high frequency imaging is needed.
Introduction of β-Diketone Unit to Polyfluorene Side Chain for Improving Color Stability and Electron Transporting Property
Authors: Cheng Jin , Kanehashi Shinji , Ogino Kenji
Published: February 2022

Poly[9,9-bis(2,4-octanedionyl)-9′,9′-di-n-octyl[2,2′-bi-9H-fluorene]-7,7′-diyl] (PFOA) was prepared with a β-diketone structure incorporated in the side chain and the optimal octyl length remained. Compared with poly(9,9-di-n-octylfluorene) (PFO) with a similar degree of polymerization, we found that the introduction of β-diketone brought about superior fluorescent, electrochemical and electron transporting properties, which suggested improved color stability and electron mobility.
Effects of Aerodynamic Drag and Drafting on Propulsive Force and Oxygen Consumption in Double Poling Cross-Country Skiing
Authors: AINEGREN MATS , LINNAMO VESA , LINDINGER STEFAN
Published: February 2022

Purpose

This study aimed to investigate the effects of aerodynamic drag and drafting on propulsive force (F
PROP), drag area (C
D
A), oxygen cost (V˙O2), metabolic rate (E˙), and heart rate (HR) during roller skiing on a treadmill in a wind tunnel using the double poling technique. A secondary aim was to investigate the effects of wind versus no-wind test conditions on the same physiological parameters.

Methods

Ten subjects of each gender participated in the experiments. One pair of skiers of the same gender roller skied simultaneously in line with the air flow; the distance between the skiers was ~2.05 m. Each pair was tested as follows: I) with wind, leading; II) with wind, drafting; and III) without wind. The treadmill inclination was 0° throughout the tests. For the wind conditions, the air velocity was similar to the treadmill belt speed: 3 to 7 m·s−1 for men and 3 to 6 m·s−1 for women.

Results

Drafting resulted in significantly (P < 0.05) lower F
PROP,
C
D
A, V˙O2, and E˙, compared with leading, for both genders at racing speed but not at lower speeds, whereas HR was only affected for the male skiers at racing speed. The test without wind resulted in significantly lower F
PROP, V˙O2, and E˙ at all tested speeds compared with the tests with wind present, whereas HR was lower only at higher speeds.

Conclusions

At racing speed, but not at lower speeds, the positive effects of drafting behind a skier during double poling were obvious and resulted in a lower F
PROP, C
D
A, V˙O2, E˙, and HR. Tests without wind present put even lower demands on the skiers’ physiology, which was also evident at lower speeds.
One Bout of Resistance Training Does Not Enhance Metformin Actions in Prediabetic and Diabetic Individuals
Authors: MORENO-CABAÑAS ALFONSO , ORTEGA JUAN FERNANDO , MORALES-PALOMO FELIX , RAMIREZ-JIMENEZ MIGUEL , ALVAREZ-JIMENEZ LAURA , MORA-RODRIGUEZ RICARDO
Published: February 2022

Purpose

This study aimed to determine the separated and combined effects of metformin and resistance exercise on glycemic control, insulin sensitivity, and insulin-like growth factor 1 (IGF-1) in overweight/obese individuals with prediabetes and type 2 diabetes mellitus.

Methods

Fourteen adults with a body mass index of 32.1 ± 4.1 kg·m−2, insulin resistance (HOMA-2 1.6 ± 0.6), and poor glycemic control (glycated hemoglobin, 6.9% ± 0.9%; 51.9 ± 10.7 mmol·mol−1) while taking metformin (1561 ± 470 g·d−1) were recruited. Participants underwent four 72-h long experimental trials in a randomized counterbalanced order, either 1) taking metformin (MET), 2) replacing metformin by placebo pills (PLAC), 3) taking placebo and undergoing a resistance training bout (RT + PLAC), and 4) taking metformin and undergoing the same RT bout (RT + MET). Interstitial fluid glucose concentration was frequently sampled to obtain 72-h glucose area under the curve (GAUC) and the percentage hyperglycemic glucose readings (>180 mg·dL−1; GPEAKS). Insulin sensitivity (i.e., HOMA-2) and IGF-1 were also assessed.

Results

HOMA-2 was not affected by treatments. GAUC and GPEAKS were similarly reduced below PLAC during RT + MET and MET (all P < 0.05). In contrast, RT + PLAC did not affect glucose concentration. Metformin decreased serum IGF-1 concentrations (P = 0.006), and RT did not reverse this reduction.

Conclusions

A bout of full-body RT does not interfere or aid on metformin’s blood glucose–lowering actions in individuals with prediabetes and type 2 diabetes mellitus.
Altitude and Endurance Performance in Altitude Natives versus Lowlanders: Insights from Professional Cycling
Authors: MATEO-MARCH MANUEL , MURIEL XABIER , VALENZUELA PEDRO L. , GANDIA-SORIANO ALEXIS , ZABALA MIKEL , BARRANCO-GIL DAVID , PALLARÉS JESÚS G. , LUCIA ALEJANDRO
Published: February 2022

Introduction

Acute altitude exposure influences exercise performance, although most research, especially regarding altitude natives, comes from laboratory data in nonathletes.

Purpose

We analyzed the influence of altitude on real-world cycling performance in top-level professional cyclists attending to whether they were altitude natives or not.

Methods

Thirty-three male cyclists (29 ± 5 yr) were studied and were classified as lowlanders (n = 19) or altitude natives (n = 14) attending to the altitude of their place of birth (431 ± 380 and 2583 ± 334 meters above sea level (m a.s.l.), respectively). Both groups included top 3 finishers (including winners) in the general classification of Grand Tours and major races. Using data from both training and competitions during years 2013–2020 (8 ± 5 seasons per cyclist), we registered participants’ mean maximal power (MMP) for efforts lasting 5 s, 30 s, 5 min, and 10 min, respectively, at altitudes ranging from 0–500 to >2000 m a.s.l.

Results

A significant altitude–MMP interaction effect (two-factor repeated-measures ANOVA) was found in lowlanders (P < 0.001) but not in altitude natives (P = 0.150). In lowlanders, individual performance decreased in a dose–response manner with increasing altitudes compared with sea (or near-sea) level (0–500 m a.s.l.), whereas this trend was much less evident in natives. A significant altitude–MMP–group effect was found (P < 0.001), with nonsignificant (and overall trivial-to-small differences) between lowlanders and altitude natives for any effort duration at altitudes ≤1500 m a.s.l. but with significant differences at higher altitudes (≥1501 m a.s.l.).

Conclusions

Acute altitude exposure influences real-world performance differently in low landers and altitude natives, which might confer a competitive advantage to the latter, particularly in races including efforts at >1500 m a.s.l.
Comparison of ten predictive equations for estimating lean body mass with dual-energy X-ray absorptiometry in older patients
Authors: Puri Tanuj , Blake Glen M
Published: February 2022

Objectives:

White fat contributes to body weight (BW) but accumulates very little [18F]fluorodeoxyglucose ([18F]FDG) in the fasting state. As a result, higher standardised uptake values normalised to BW (SUV) are observed in non-fatty tissue in obese patients compared to those in non-obese patients. Therefore, SUV normalised to lean body mass (SUL) that makes tumour uptake values less dependent on patients’ body habitus is considered more appropriate. This study aimed to assess ten mathematical equations to predict lean body mass (LBM) by comparison with dual-energy X-ray absorptiometry (DXA) as the reference method.

Methods:

DXA-based LBM was compared with ten equation-based estimates of LBM in terms of the slope, bias and 95% limits of agreement (LOA) of Bland-Altman plots, and Pearson correlation coefficients (r). Data from 747 men and 811 women aged 60–65 years were included.

Results:

Gallagher’s equation was optimal in males (slope = 0.13, bias = −2.4 kg, LOA = 12.8 kg and r = 0.900) while Janmahasatian’s equation was optimal in females (slope = 0.14, bias = −0.9 kg, LOA = 10.7 kg and r = 0.876). Janmahasatian’s equation performed slightly better than Gallagher’s in the pooled male and female data (slope = 0.00, bias = −1.6 kg, LOA = 12.3 kg and r = 0.959).

Conclusions:

The Gallagher and Janmahasatian equations were optimal and almost indistinguishable in predicting LBM in subjects aged 60–65 years.

Advances in knowledge:

Determination of the optimum equation for predicting lean body mass to improve the calculation of SUL for [18F]FDG PET quantification.