bluuebunny/crossref_metadata_2025 huggingface dataset:
Differences in the dielectric properties of various benign and malignant thyroid nodules
Authors: Huang Shengyi , Cai Weizhen , Han Shuai , lin Yu , Wang Yu , Chen Fei , Shao Guoli , Liu Yonghong , Yu Xuefei , Cai Zhai , Zou Zenan , Yao Shun , Wang Qiaohui , Li Zhou
Published: October 2020

Purpose

This experiment was conducted to investigate the dielectric properties of different types of thyroid nodules. Our goal was to find a simple and fast method to detect thyroid diseases at different stages from the dielectric properties of thyroid nodules.

Methods

We used the open‐ended coaxial line method to measure the dielectric permittivities of thyroid tissues from 155 patients at frequencies ranging from 1 to 4000 MHz. Tissues that were investigated included normal thyroid tissue and benign and malignant thyroid nodules (nodular goiter, follicular adenoma, papillary carcinoma, and follicular carcinoma), as determined from pathological reports. Differences in dielectric properties were measured between each nodule and the surrounding 1 cm of tissue.

Results

The analysis results revealed that the dielectric permittivity and conductivity values were positively correlated with the degree of malignancy of the nodule (normal < benign < malignant; all differences P < 0.05). This was more obvious at frequencies within 20~70 MHz, following the order normal tissue < nodular goiter < follicular adenoma < papillary carcinoma < follicular carcinoma. A significant difference (P < 0.05) in dielectric permittivity and conductivity was found when comparing these nodules with the surrounding 1 cm of tissue.

Conclusions

Normal, benign, and malignant nodules were successfully distinguished from one another, and dielectric permittivity was found to be a more sensitive parameter than conductivity. In particular, different disease types can be distinguished at a stimulation frequency of 20~70 MHz, which shows that dielectric properties have application prospects for the detection and diagnosis of cancer. At the same time, the dielectric parameter differences between the surrounding 1 cm of tissue and the diseased nodule can distinguish the tumor and its surrounding tissues in real time during surgery to determine the tumor boundary.
Deep learning‐based radiomics predicts response to chemotherapy in colorectal liver metastases
Authors: Wei Jingwei , Cheng Jin , Gu Dongsheng , Chai Fan , Hong Nan , Wang Yi , Tian Jie
Published: October 2020

Purpose

The purpose of this study was to develop and validate a deep learning (DL)‐based radiomics model to predict the response to chemotherapy in colorectal liver metastases (CRLM).

Methods

In this retrospective study, we enrolled 192 patients diagnosed with CRLM who received first‐line chemotherapy and were followed by response assessment. Tumor response was identified according to the Response Evaluation Criteria in Solid Tumors (RECIST). Contrast‐enhanced multidetector computed tomography (MDCT) images were fed as inputs of the ResNet10‐based DL radiomics model, and the possibility of response was predicted as the output. The final combined DL radiomics model was constructed by integrating the response‐related clinical factors and the developed DL radiomics signature. A time‐independent validation cohort (n = 48) was extracted from the 192 patients to evaluate the DL model with area under the receiver operating characteristic curve (AUC), specificity, and sensitivity. Meanwhile, a traditional radiomics model was constructed using least absolute shrinkage and selection operator (lasso) as comparisons with the DL‐based model.

Results

According to RECIST criteria, 131 patients were identified as responders with complete response, partial response, and stable disease, while 61 patients were nonresponders with progression disease. The selected predictive clinical factor turned out to be the carcinoembryonic antigen (CEA) level with AUC of 0.489 (95% confidence interval [CI], 0.380–0.599) and 0.558 (95% CI, 0.374–0.741) in the training and validation cohorts, respectively. The DL‐based model provided better performance than the traditional classifier‐based radiomics model with significantly higher AUC (training: 0.903 [95% CI, 0.851–0.955] vs 0.745 [95% CI, 0.659–0.831]; validation: 0.820 [95% CI, 0.681–0.959] vs 0.598 [95% CI, 0.422–0.774]). The combination of DL‐based model with the CEA level provided slightly increased performance with AUC of 0.935 [95% CI, 0.897–0.973] in the training cohort and 0.830 [95% CI, 0.688‐0.973] in the validation cohort.

Conclusions

The developed DL‐based radiomics model could improve the efficiency to predict the response to chemotherapy in CRLM, which may assist in subsequent personalized treatment decision‐making in CRLM management.
Patient‐reported outcomes in the setting of a randomized control trial on the efficacy of transcutaneous stimulation of the posterior tibial nerve compared to percutaneous stimulation in idiopathic overactive bladder syndrome
Authors: Ramírez‐García Inés , Kauffmann Stéphanie , Blanco‐Ratto Laia , Carralero‐Martínez Andrea , Sánchez Emília
Published: October 2020

Aim

To compare the efficacy of transcutaneous tibial nerve stimulation (TTNS) with percutaneous tibial nerve stimulation (PTNS) regarding patient‐reported outcomes measures, specifically quality‐of‐life (QoL) improvement and patient's treatment benefit, on symptoms associated with overactive bladder (OAB).

Methods

Patients with refractory OAB symptoms and detrusor overactivity were randomized to receive TTNS or PTNS for 12 weeks. Data from self‐report OAB questionnaire short form (q‐SF) and incontinence (I)‐QoL questionnaires were collected pretreatment and at Weeks 6 and 12. Patients’ self‐perceived benefits on symptoms (treatment benefit scale, TBS) were also gathered. Mean change in scores within and between groups were estimated.

Results

Sixty‐eight adult patients (67.6% women) were included in the intention to treat analysis. Of those, 61 completed all questionnaires and were analyzed as per protocol. Statistically significant improvements in OAB‐q‐SF and I‐QoL between baseline and end‐of‐treatment scores were observed in both TTNS and PTNS groups (p < .001), being the differences much higher than the minimal important difference in both questionnaires. The scores of the OAB‐q‐SF scales (symptoms bother and health‐related QoL) showed no statistically significant differences between the two groups. Similarly, the differences regarding the I‐QoL questionnaire were statistically nonsignificant either (p = .607). When assessing the treatment benefit on symptoms, TBS responses between groups showed no statistical differences.

Conclusion

A significant improvement of QoL was observed in both TTNS and PTNS groups. However, no patient‐reported outcomes measures scores support a difference between the two groups. Therefore, these findings along with TTNS ease of application and less invasiveness may lead to an increased indication of this technique for OAB.
Symptoms and noninvasive test parameters that clinically differentiate detrusor underactivity from bladder outlet obstruction without a pressure‐flow‐based diagnosis in men with lower urinary tract symptoms
Authors: Takahashi Ryosuke , Takei Mineo , Namitome Ryo , Yamaguchi Osamu , Eto Masatoshi
Published: October 2020

Aim

To examine the symptoms and noninvasive test parameters that clinically differentiate detrusor underactivity (DU) from bladder outlet obstruction (BOO) without using a pressure‐flow study (PFS) in male patients with lower urinary tract symptoms.

Methods

We examined 909 men who underwent PFS and also had the following data: International Prostate Symptom Score (IPSS), free uroflowmetry, postvoid residual (PVR), and prostate volume (PV). Using these data, significant symptoms and noninvasive test parameters that clinically differentiate DU from BOO were examined.

Results

Significant parameters between DU patients and BOO patients were older age, smaller PV, and lower urgency symptom score (IPSS Q4). Optimal cutoff values were determined using receiver operating characteristic curves (≥74 years old, PV ≤ 34.8, and IPSS Q4 ≤ 1) and patients were categorized on the basis of the number of significant factors. The probability of DU or BOO in patients with three significant factors were 77% and 34%, respectively.

Conclusion

Three factors (older age, smaller PV, and fewer urgency symptom) were the predictive factors to differentiate DU from BOO, which might be useful for estimating the probability of DU in clinical practice without a PFS.
Testing a new, intensified infusion‐withdrawal protocol for urinary urgency provocation in brain‐bladder studies
Authors: Clarkson Becky D , Karim Helmet T , Griffiths Derek J , Resnick Neil M
Published: October 2020

Introduction

The brain's role in bladder control has become an important area of study in the last 15 years. Typically, the brain's role in urinary urgency has been studied by repeated infusion and withdrawal of fluid, per catheter, to provoke urgency sensation during a whole brain magnetic resonance imaging (MRI) scan. Since this technique generally requires a large group size, we tested a more intense infusion‐withdrawal protocol in an attempt to improve signal to noise ratio and repeatability of the signal which would, in turn, allow us to further probe subtypes of urgency urinary incontinence.

Methods

A total of 12 women over the age of 60 were recruited to test a new “intense” infusion withdrawal protocol. They underwent this new protocol during a functional brain MRI scan. The primary outcome was comparison of activity within the insula, medial pre‐frontal cortex and dorsal anterior cingulate cortex/supplementary motor area (dACC/SMA). Immediate test‐retest repeatability was measured using intraclass correlation. Secondary exploratory evaluation of differences in the whole brain between protocols was conducted.

Results

There was no significant difference in signal in any of the a priori regions of interest between protocols. Test‐retest repeatability in the new protocol was poor compared to the original protocol, and variability was higher. Three participants were not able to tolerate the “intense” protocol.

Conclusion

The small improvement in signal to noise ratio of the new protocol was not sufficient to overcome the poorly tolerated intense filling protocol.
In vivo investigation of the multi‐exponentialT2decay in human white matter at 7 T: Implications for myelin water imaging at UHF
Authors: Wiggermann Vanessa , MacKay Alexander L. , Rauscher Alexander , Helms Gunther
Published: October 2020

Introduction

Multi‐componentT2mapping using a gradient‐ and spin‐echo (GraSE) acquisition has become standard for myelin water imaging at 3 T. Higher magnetic field strengths promise signal‐to‐noise ratio benefits but face specific absorption rate limits and shortenedT2times. This study investigates compartmentalT2times in vivo and addresses advantages and challenges of multi‐componentT2mapping at 7 T.

Methods

We acquired 3D multi‐echo GraSE data in seven healthy adults at 7 T, with three subjects also scanned at 3 T. Stimulated echoes arising fromB1+inhomogeneities were accounted for by the extended phase graph (EPG) algorithm. We used the computedT2distributions to determineT2times that identify different water pools and assessed signal‐to‐noise and fit‐to‐noise characteristics of the signal estimation. We compared shortT2fractions andT2properties of the intermediate water pool at 3 T and 7 T.

Results

Flip angle mapping confirmed that EPG accurately determined the largerB1+inhomogeneity at 7 T. Multi‐componentT2analysis demonstrated shortenedT2times at 7 T compared with 3 T. Fit‐to‐noise and signal‐to‐noise ratios were improved at 7 T but depended onB1+homogeneity. Adjusting the shortestT2to 8 ms and theT2threshold that separates different water compartments to 20 ms yielded shortT2fractions at 7 T that conformed to 3 T data. ShortT2fractions in myelin‐rich white matter regions were lower at 7 T than at 3 T, and higher in iron‐rich structures.

Discussion

Adjusting theT2compartment boundaries was required due to the shorterT2relaxation times at 7 T. Shorter echo spacing would better sample the fast decaying signal but would increase peripheral nerve stimulation. Multi‐channel transmission will improveT2measurements at 7 T.

Conclusion

We used a multi‐echo 3D GraSE sequence to characterize the multi‐exponentialT2decay at 7 T. We adaptedT2parameters for evaluation of the shortT2fraction. Obtained 7 T multi‐componentT2maps were in good agreement with 3 T data.
A fractional model for population dynamics of two interacting species by using spectral and Hermite wavelets methods
Authors: Kumar Sunil , Ghosh Surath , Kumar Ranbir , Jleli Mohamed
Published: October 2020

The Lotka‐Volterra model is a very famous model and frequently used to describe the dynamics of ecological systems in which two species interact, one a predator and one its prey. In this present work, a comparative study is presented for solving Lotka‐Volterra model which has an important role in Biological sciences. The Lotka‐Volterra equations are solved by spectral collocation method (SCM) by using shifted Chebyshev polynomials of first kind. Then, a numerical example with two different cases is presented to demonstrate the accuracy and effectiveness of the numerical schemes. Using spectral method, we get a system of nonlinear algebraic equations which are solved by Newton's iteration method. Also the achieved solutions are compared with another solutions obtained by the Hermite wavelets method (HWM). Further, this work reflects that the integer order Lotka‐Volterra model and the fractional order one have close relationship where integer order model is a special case of fractional order. The behaviors study of predator and prey populations due to presence of fractional derivative are the key features of the present work. Our numerical and graphical results indicate that the proposed methods are simple, powerful and fully compatible for treatment of the Lotka‐Volterra model of fractional order.
‘On a nos mots à dire’: Kanak Women's Experience of Bridewealth in Lifou
Authors: Paini Anna
Published: October 2020

Bridewealth in Lifou cannot be discussed on its own; rather it should be considered within the plurality of ceremonial acts which are needed to legitimize a marriage as customary. What do these transactions mean? Where does women's agency lie? Through a longitudinal analysis of ethnographic materials from my fieldwork in Lifou, Loyalty Islands, I consider how Kanak women are engaged in and perceive these ceremonial and cultural processes through a declared women's perspective that highlights their ability to make autonomous choices in an open ended historical context. I argue that it is a case of ‘positive agency’. I emphasize that local categories (june hmala and wenehleng) which define specific moments in this process can be subsumed under the anthropological term ‘bridewealth’. Further, I examine the meaning of money in bridewealth and the fact that the monetary contribution keeps increasing, raising local concerns about the need to regulate the amount circulating in marriage exchanges and its dispersion. Furthermore in Lifou there is no indication that the assembling of the bridewealth by the grooms implies a commoditization and (later) exploitation of women.
Thiophene‐based polyphosphazenes with tunable optoelectronic properties
Authors: Ogueri Kennedy S. , Ogueri Kenneth S. , Laurencin Cato T. , Allcock Harry R.
Published: October 2020

The polyphosphazene backbone provides a versatile platform to explore numerous synthesis and structure–property relationships for many technological applications. In this study, a new class of polyphosphazene semiconducting materials was synthesized via macromolecular substitution, which integrates a PN backbone with thiophene‐based side groups. The synthesized thiophene‐based polymers were subjected to chemical oxidation (oxidative coupling) to optimize their optoelectronic properties through side‐chain chemistry. Both the spectroscopic and electronic analyses revealed that optical and electronic properties, as well as glass transition temperatures could be modulated by chemical oxidation of the polymers. The suitability of the polymers as potential semiconductors was further evaluated using their steady‐state fluorescence quenching behavior in the presence of four different dopants (PC70BM, PC60BM, F4TCNQ, and TCNQ). It was found that the addition of dopant as a quencher to the polymer solutions does not form a complex in the ground state, and its excited state shows an efficient decrease in fluorescence intensity without altering the shape and peak position of the fluorescence band. The overall results demonstrate that the utilization of chemical oxidation via side‐chain chemistry of polyphosphazenes offers an adaptable toolbox that can be used to make new and potentially useful polymeric semiconductors for applications in organic electronics.
The nature of ammonium nitrate decomposition and explosions
Authors: Willey Ronald J.
Published: October 2020

Ammonium nitrate explosions can cause significant destruction as shown with examples in West, Texas (2013) and Tianjin, China (2015). Yet, ammonium nitrate is available in nearly every garden center, and serves as one of the major fertilizers used throughout the world. Why is it safe to store in a garden center, and yet not safe when stored in wooden framed buildings? This presentation explores the nature of ammonium nitrate decomposition steps using a process simulator where adiabatic, constant pressure, and constant volume scenarios are evaluated. Answers are simple, yet complex. The first decomposition step is endothermic. In other words, there is a natural barrier that needs to be overcome before further decomposition. Further explanations are offered within the paper.
Polycentric development and local fertility in metropolitan regions: An empirical analysis for Barcelona, Spain
Authors: López‐Gay Antonio , Salvati Luca
Published: October 2020

The present study verifies if spatial variability in local fertility reflects the shift from a monocentric dense settlement model towards a polycentric metropolis organised in central cores and subcentral locations. The spatial distribution of a crude birth rate in Barcelona's province was investigated for a long time span (1975–2018), identifying distinctive trends within five concentric rings around Barcelona at four subperiods (1975–1985, 1986–1996, 1997–2007 and 2008–2018). Using multivariate exploratory statistics, local fertility rates were correlated with background indicators delineating the socio‐economic profile of each municipality in the study area. Fertility rates decreased with the distance from downward Barcelona and with population density. In the first time interval (1975–1985), fertility levels—higher in subcentral municipalities and peri‐urban locations than in downtown Barcelona—were positively associated with urban growth. In the following two subperiods (1986–1996 and 1997–2007), the contribution of local fertility to urban growth decreased significantly, reaching the lowest‐low figures at the end of the 1980s. In the most recent time interval (2008–2018), a moderate (and spatially heterogeneous) recovery of fertility rates was observed in subcentral locations. Demographic processes underlying Barcelona's expansion provide evidence in favour of a positive relationship between polycentric development and local fertility. Our article finally debates on the use of fertility indicators in the assessment of monocentric versus polycentric (metropolitan) growth in advanced economies.
Protocatechualdehyde attenuates obstructive nephropathy through inhibiting lncRNA9884 induced inflammation
Authors: Yang Jieke , Li Jianchun , Tan Ruizhi , He Xingcan , Lin Xiao , Zhong Xia , Fan Junming , Wang Li
Published: October 2020

Persistent chronic inflammation and fibrosis product accumulation aggravate tubulointerstitial fibrosis (TIF), leading to the progression of chronic kidney disease. The aim of this study was designed to investigate the effect of protocatechualdehyde (PCA), a natural phenolic acid compound isolated from Salvia miltiorrhiza, on the unilateral ureteral obstruction (UUO)‐induced fibrosis and inflammation and to elucidate the underlying mechanism in primary renal tubular epithelial cells (TECs). Results from the histology suggested that the moderate to severe deteriorations of renal dysfunction and the pathological changes in UUO could be relieved by PCA treatment. Mechanistic studies revealed that the effect of PCA was associated with the downregulation of Smad3 and NF‐κB driven fibrosis and inflammation respectively. It is worth noting that PCA could inhibit the aberrant expression of inflammation cytokines such as iNOS, MCP‐1, TNF‐α in UUO, and IL‐1β‐treated TECs. In addition, PCA also suppressed the expression of Smad3‐dependent long noncoding RNA (lncRNA), 9884. Importantly, when overexpressing of lncRNA9884 in TECs by transfection of pcDNA3.1‐lncRNA9884 plasmid, it revealed significant reversal of protein expression levels as that observed with only PCA, suggesting that PCA inhibits inflammation by mediating lncRNA9884/MCP‐1 signaling pathway. Collectively, the current study establishes a foundational basis for PCA in future treatment of obstructive nephropathy.
Protective effects of irigenin against 1‐methyl‐4‐phenylpyridinium‐induced neurotoxicity through regulating the Keap1/Nrf2 pathway
Authors: Guo Fen , Wang Xiaoxue , Liu Xinxin
Published: October 2020

The rhizome of Belamcanda chinensis possesses antiinflammatory and antioxidant activities. However, the effect of irigenin, isolated from the rhizome of B. chinensis, on 1‐methyl‐4‐phenylpyridinium (MPP+)‐induced neurotoxicity is unknown. MTT assay showed that MPP+ exposure dose dependently inhibited the viability of mouse microglia BV‐2 cells, whereas irigenin suppressed MPP+‐induced viability reduction. The production of nitric oxide, prostaglandin E2, tumor necrosis factor‐α and interleukin‐6 were increased by MPP+ treatment, which were abolished by irigenin treatment. Irigenin‐attenuated MPP+‐induced increase of malondialdehyde content and activities of superoxide dismutase, catalase and glutathione peroxidase in BV‐2 cells. Irigenin treatment also repressed apoptosis, caspase‐3/7 activity and Cytochrome C expression in MPP+‐challenged BV‐2 cells. Interestingly, irigenin activated the Keap1/Nrf2 pathway in MPP+‐induced BV‐2 cells. Nrf2 knockdown attenuated the effects of irigenin on MPP+‐induced viability reduction, inflammation, oxidative stress and apoptosis in BV‐2 cells. In conclusion, irigenin alleviated MPP+‐induced neurotoxicity in BV‐2 cells through regulating the Keap1/Nrf2 pathway.
Adaptive sequential predictive maintenance policy with nonperiodic inspection for hard failures
Authors: Wu Lang , Zhou Qiang
Published: October 2020

This paper proposes a novel adaptive maintenance policy for degrading systems subject to hard failure. Compared with traditional condition‐based maintenance policies, the proposed predictive maintenance policy makes maintenance decisions adaptively based on model prognostic results. The prognostic model is continuously updated based on newly inspected data. The inspection times and preventive maintenance activities are scheduled online in a sequential manner based on the most current prediction of system reliability. A computationally efficient optimization scheme is proposed for obtaining optimal maintenance parameters. The proposed policy is demonstrated and its performance is evaluated through extensive simulations.
Does the timing of integrating new skills affect start‐up growth?
Authors: Grillitsch Markus , Schubert Torben
Published: October 2020

Research Summary

Growth often requires start‐ups to recruit new skills not present in the founding team. We analyze if the relationship between integrating new skills and growth depends on timing. Should new skills be recruited as early as possible, or can start‐ups add them as needed along the way? Using a unique panel dataset covering Sweden's population of start‐ups from 1997 to 2012, our analysis shows that (a) start‐ups' growth rate is positively correlated with integrating novel skills early in their life, while adding novel skills later is associated with lower growth and (b) corporate spin‐offs profit less from recruiting novel skills than de novo start‐ups. We mirror our results against existing theories and develop theoretical perspectives for future research.

Managerial Summary

Entrepreneurs and managers of start‐ups need to develop the competences of their company as it matures. For this, they typically need to hire qualified personnel. But when is the best time to do so? In this paper, we show that the costs of integrating new skills from recruitment increase over time. We show that in order to achieve high firm growth there is a window of opportunity for successful recruitment covering the first 3–4 years after the founding of the company. Recruiting novel skills after this period is associated with reduced firm growth. Our results are thus in favor of a hiring strategy, where needed skills are recruited as early as possible.
The implications of noncompliance for randomized trials with partial nesting due to group treatment
Authors: Roberts Chris
Published: October 2020

Analyses of trials of group administered treatments require an identifier for therapy group to account for clustering by group. All patients randomized to receive the group administered treatment could be assigned an intended group identifier following randomization. Alternatively, an actual group could be based on those patients that comply with group therapy. We investigate the implications for intention‐to‐treat (ITT) analyses of using either the intended or actual group to adjust for the clustering effect. We also consider causal models using the actual group. A simulation study showed that ITT estimates based on random effects models or GEE with an exchangeable correlation matrix performed much better when using the intended group than the actual group. OLS with robust standard errors performed well with both. Most compliance average causal effect (CACE) models performed well. While practical constraints of the clinical setting may determine the choice between an intended or actual group analyses, it is desirable to record both. An ITT analysis using mixed models can then be fitted using the intended group with data generation assumptions checked by a causal model using the actual group. Where an ITT analysis is based on the actual group, worse outcome for never‐takers than compliers may allow one to infer that some estimators are biased toward no treatment effect. The work here is motivated and illustrated by a trial of a group therapy, but also has relevance to trials with treatment related clustering due to therapist examples of which include physical and talking therapies or surgery.
Recent Advances in 1D Electrospun Nanocatalysts for Electrochemical Water Splitting
Authors: Zhang Longcheng , Zhao Haitao , Xu Siran , Liu Qian , Li Tingshuai , Luo Yonglan , Gao Shuyan , Shi Xifeng , Asiri Abdullah M. , Sun Xuping
Published: October 2020

Electrochemical water splitting, as a promising sustainable‐energy technology, has been limited by its slow kinetics and large overpotential. This shortcoming necessitates the design of 1D nanocatalysts with large surface area, high electronic conductivity, and easily tunable composition. Herein, recent progress about electrocatalytic water splitting based on the advanced electrospun nanomaterials is reviewed. First, the related fundamentals of electrochemical water splitting according to two main aspects are discussed as follows: hydrogen evolution reaction and oxygen evolution reaction. Second, the structure design and the electrocatalytic properties of electrospun nanomaterials according to difference in component (including single metal‐based electrocatalysts, metal alloy‐based electrocatalysts, metal oxide‐based electrocatalysts, metal sulfide‐based electrocatalysts, metal phosphide‐based electrocatalysts, metal carbide‐based electrocatalysts, etc.) are summarized. Finally, the future perspectives and challenges for designing next‐generation 1D electrospun nanocatalysts for electrochemical water splitting are concluded.
Selection signatures across seven decades of hard winter wheat breeding in the Great Plains of the United States
Authors: Ayalew Habtamu , Sorrells Mark E. , Carver Brett F. , Baenziger P. Stephen , Ma Xue‐Feng
Published: October 2020

Classical plant breeding has been instrumental in changing the genetic makeup of crop plants for better ecological adaptation and improved quality. This paper provides insights of the genomic changes effected in hard winter wheat (Triticum aestivum L.) through decades of breeding and selection in the Great Plains of the United States. Population structure and differentiation analyses were conducted on 185 wheat cultivars released from 1943 to 2013. Cultivars were grouped into four distinct clusters using discriminant analysis of principal components (DAPC). One of the clusters was unique in that 15 out of the 18 individuals were recent releases (2000–2010), while 12 of the 18 shared the cultivar ‘Jagger’ in their genetic background. Jagger carries a 2NS/2AS translocation segment from Aegilops ventricosa, an important segment for resistance to several foliar diseases. Using the outlier approach, Wright's population fixation index (Fst) identified 450 loci that were directionally selected. The largest signature of selection was found on chromosome 2A. Genetic diversity was high while the inbreeding coefficient was low, indicating extensive hybridization and germplasm exchange among breeding programs within the region. Foliar disease pressure and selection for resistance helped shape the microevolution of wheat in the southern Great Plains. The results showed that high genetic diversity remains in hard winter wheat cultivars adapted to the Great Plains of the USA, and modern plant breeding did not cause any sizable reduction in genetic diversity of the crop in this region.
Echocardiographic evaluation in Dorper ovine fetuses: Applications and limitations
Authors: Cruz‐Aleixo Amanda Sarita , Lima Mayra de Castro Ferreira , Albuquerque Ana Luísa Holanda de , Teixeira Raphael Tortorelli , Paula Renata Alves de , Grandi Marina Cecília , Ferreira Danilo Otávio Laurenti , Tsunemi Miriam Harumi , Chiacchio Simone Biagio , Lourenço Maria Lucia Gomes
Published: October 2020

In this study we aim to show the application of ultrasound evaluation of the fetal heart in the ovine species, as well as its limitations in the field. Ten Dorper sheep, without any sedation, were evaluated starting from the second month of pregnancy through transabdominal ultrasound with an ultrasound device equipped with a convex transducer. Images of the fetal heart were obtained through maternal abdominal ultrasound by identifying the position of the fetus and conducting the following measurements: length and diameter of the heart, dimensions of the right and left ventricles and dimensions of the right and left atria. The measurements could only be conducted with acceptable precision starting from the third month of pregnancy. There was a significant difference only for left ventricle diameter, which was larger in the fifth month of pregnancy. The echocardiographic evaluation of the fetus enables monitoring the heart development identifying early fetal viability, assessing inadequate events that could put the pregnancy at risk, especially for production animals. For the experimental design of research employing production animals, it is important to consider, among other factors, the limitations of the evaluation on the field, such as restraining the animals, the stress caused by handling and environmental conditions, temperature, luminosity, facilities available and the qualifications of the team.
Three-dimensional Maxwellian extended Newtonian gravity and flat limit
Authors: Concha Patrick , Ravera Lucrezia , Rodríguez Evelyn , Rubio Gustavo
Published: October 2020

Abstract

In the present work we find novel Newtonian gravity models in three space-time dimensions. We first present a Maxwellian version of the extended Newtonian gravity, which is obtained as the non-relativistic limit of a particular U(1)-enlargement of an enhanced Maxwell Chern-Simons gravity. We show that the extended Newtonian gravity appears as a particular sub-case. Then, the introduction of a cosmological constant to the Maxwellian extended Newtonian theory is also explored. To this purpose, we consider the non-relativistic limit of an enlarged symmetry. An alternative method to obtain our results is presented by applying the semigroup expansion method to the enhanced Nappi-Witten algebra. The advantages of considering the Lie algebra expansion procedure is also discussed.
Magnetic catalysis and the chiral condensate in holographic QCD
Authors: Ballon-Bayona Alfonso , Shock Jonathan P. , Zoakos Dimitrios
Published: October 2020

Abstract

We investigate the effect of a non-zero magnetic field on the chiral condensate using a holographic QCD approach. We extend the model proposed by Iatrakis, Kiritsis and Paredes in [1] that realises chiral symmetry breaking dynamically from 5d tachyon condensation. We calculate the chiral condensate, magnetisation and susceptibilities for the confined and deconfined phases. The model leads, in the probe approximation, to magnetic catalysis of chiral symmetry breaking in both confined and deconfined phases. In the chiral limit, mq = 0, we find that in the deconfined phase a sufficiently strong magnetic field leads to a second order phase transition from the chirally restored phase to a chirally broken phase. The transition becomes a crossover as the quark mass increases. Due to a scaling in the temperature, the chiral transition will also be interpreted as a transition in the temperature for fixed magnetic field. We elaborate on the relationship between the chiral condensate, magnetisation and the (magnetic) free energy density. We compare our results at low and moderate temperatures with lattice QCD results.
Odd and Even Major Indices and One-Dimensional Characters for Classical Weyl Groups
Authors: Brenti Francesco , Sentinelli Paolo
Published: October 2020

We define and study odd and even analogues of the major index statistics for the classical Weyl groups. More precisely, we show that the generating functions of these statistics, twisted by the one-dimensional characters of the corresponding groups, always factor in an explicit way. In particular, we obtain odd and even analogues of Carlitz’s identity, of the Gessel–Simion Theorem, and a parabolic extension, and refinement, of a result of Wachs.
The effects of caffeine on olfactory function and mood: an exploratory study
Authors: Stafford Lorenzo D. , Orgill Kaylee
Published: October 2020

Caffeine has been demonstrated to enhance olfactory function in rodents, but to date, the sparse research in humans has not shown any equivalent effects. However, due to the methodological nature of those human studies, a number of questions remain unanswered, which the present study aimed to investigate. Using a double-blind experimental design, participants (n = 40) completed baseline mood measures, standardised threshold and identification tests and were then randomly allocated to receive a capsule containing either 100 mg of caffeine or placebo, followed by the same olfactory tests and mood measures. Results revealed that despite a trend toward elevated arousal following caffeine for habitual caffeine consumers, there were no changes in odour function. In contrast, for non-caffeine consumers, caffeine acted to enhance odour (threshold) sensitivity but reduce odour identification. Overall, these findings demonstrate a complex profile of effects of caffeine on odour function and, given the evidence from the wider caffeine literature, it is proposed that the effects of caffeine might be limited to older populations.
Adduct annotation in liquid chromatography/high-resolution mass spectrometry to enhance compound identification
Authors: Stricker Thomas , Bonner Ron , Lisacek Frédérique , Hopfgartner Gérard
Published: October 2020

Annotation and interpretation of full scan electrospray mass spectra of metabolites is complicated by the presence of a wide variety of ions. Not only protonated, deprotonated, and neutral loss ions but also sodium, potassium, and ammonium adducts as well as oligomers are frequently observed. This diversity challenges automatic annotation and is often poorly addressed by current annotation tools. In many cases, annotation is integrated in metabolomics workflows and is based on specific chromatographic peak-picking tools. We introduce mzAdan, a nonchromatography-based multipurpose standalone application that was developed for the annotation and exploration of convolved high-resolution ESI-MS spectra. The tool annotates single or multiple accurate mass spectra using a customizable adduct annotation list and outputs a list of [M+H]+ candidates. MzAdan was first tested with a collection of 408 analytes acquired with flow injection analysis. This resulted in 402 correct [M+H]+ identifications and, with combinations of sodium, ammonium, and potassium adducts and water and ammonia losses within a tolerance of 10 mmu, explained close to 50% of the total ion current. False positives were monitored with mass accuracy and bias as well as chromatographic behavior which led to the identification of adducts with calcium instead of the expected potassium. MzAdan was then integrated in a workflow with XCMS for the untargeted LC-MS data analysis of a 52 metabolite standard mix and a human urine sample. The results were benchmarked against three other annotation tools, CAMERA, findMAIN, and CliqueMS: findMAIN and mzAdan consistently produced higher numbers of [M+H]+ candidates compared with CliqueMS and CAMERA, especially with co-eluting metabolites. Detection of low-intensity ions and correct grouping were found to be essential for annotation performance.
Diffusion magnetic resonance imaging assessment of regional white matter maturation in preterm neonates
Authors: Kimpton J. A. , Batalle D. , Barnett M. L. , Hughes E. J. , Chew A. T. M. , Falconer S. , Tournier J. D. , Alexander D. , Zhang H. , Edwards A. D. , Counsell S. J.
Published: October 2020

Purpose

Diffusion magnetic resonance imaging (dMRI) studies report altered white matter (WM) development in preterm infants. Neurite orientation dispersion and density imaging (NODDI) metrics provide more realistic estimations of neurite architecture in vivo compared with standard diffusion tensor imaging (DTI) metrics. This study investigated microstructural maturation of WM in preterm neonates scanned between 25 and 45 weeks postmenstrual age (PMA) with normal neurodevelopmental outcomes at 2 years using DTI and NODDI metrics.

Methods

Thirty-one neonates (n = 17 male) with median (range) gestational age (GA) 32+1 weeks (24+2–36+4) underwent 3 T brain MRI at median (range) post menstrual age (PMA) 35+2 weeks (25+3–43+1). WM tracts (cingulum, fornix, corticospinal tract (CST), inferior longitudinal fasciculus (ILF), optic radiations) were delineated using constrained spherical deconvolution and probabilistic tractography in MRtrix3. DTI and NODDI metrics were extracted for the whole tract and cross-sections along each tract to assess regional development.

Results

PMA at scan positively correlated with fractional anisotropy (FA) in the CST, fornix and optic radiations and neurite density index (NDI) in the cingulum, CST and fornix and negatively correlated with mean diffusivity (MD) in all tracts. A multilinear regression model demonstrated PMA at scan influenced all diffusion measures, GA and GAxPMA at scan influenced FA, MD and NDI and gender affected NDI. Cross-sectional analyses revealed asynchronous WM maturation within and between WM tracts.).

Conclusion

We describe normal WM maturation in preterm neonates with normal neurodevelopmental outcomes. NODDI can enhance our understanding of WM maturation compared with standard DTI metrics alone.
BnSIP1-1 Involves in Light Response and Regulation of Endogenous Hormones and Flowering Time of Brassica Napus
Authors: Luo Junling , Jiang Weihua , Tang Shaohua , Mei Fengling , Yan Xiaohong , Zeng Xinhua , Wu Gang
Published: October 2020

BnSIP1-1 is a trihelix transcription factor family gene which functions in abiotic stress response and abscisic acid (ABA) signaling during seed germination and seedling growth of Brassica napus. In the present study, further sequence analysis and phenotype identification indicated that this gene had roles in light regulation and flowering of reproductive growth stage. Many phytohormones responsive cis-acting elements, including TC-rich repeats, GARE-motif, and TCA and TGA elements, were identified in the promoter sequence of BnSIP1-1. The expression of BnSIP1-1 was regulated by light period and remarkable higher expression level of BnSIP1-1 was detected in roots than in leaves. Overexpression of BnSIP1-1 in Arabidopsis delayed flowering time for 3–5 days in transgenic plants. In addition, we also found BnSIP1-1 can respond to abiotic and ABA stress (treated with 200 mM NaCl, 300 mM mannitol or 50 μM ABA for 0, 1, 6, and 24 h) in B. napus through adjusting not only ABA but also other endogenous hormones, including indole-3-acetic acid and salicylic acid. Moreover, jasmonates (JA) signaling pathway was found not involving in the pathway of BnSIP1-1 responding to abiotic stresses.
Global value chains and technology transfer: new evidence from developing countries
Authors: Rigo Davide
Published: October 2020

International trade has long been considered a channel of technology transfer. This paper draws from the World Bank’s Enterprise Surveys to provide a sample of 18 developing and emerging economies to investigate whether global value chains (GVCs) are a vehicle for the transfer of technology. It focuses on one specific channel for technology transfer, namely, the licensing of foreign technology. To control for the possible endogeneity of technology licensing, propensity score matching is combined with a difference-in-differences approach. The results show a positive effect of being involved in two-way trading on the licensing of foreign technology. Firms that become two-way traders are significantly more likely to use foreign-licensed technology than firms starting to export or import. This evidence suggests that the complexity associated with the mode of internationalisation determines the licensing of foreign technology. GVC participation also appears to foster firms’ performance, reflecting my findings that the acquisition of foreign technology leads to significant productivity improvements.
Camera-guided Weed Hoeing in Winter Cereals with Narrow Row Distance
Authors: Gerhards Roland , Kollenda Benjamin , Machleb Jannis , Möller Kurt , Butz Andreas , Reiser David , Griegentrog Hans-Werner
Published: October 2020

Farmers are facing severe problems with weed competition in cereal crops. Grass-weeds and perennial weed species became more abundant in Europe mainly due to high percentages of cereal crops in cropping systems and reduced tillage practices combined with continuous applications of herbicides with the same mode of action. Several weed populations have evolved resistance to herbicides. Precision weed hoeing may help to overcome these problems. So far, weed hoeing in cereals was restricted to cropping practices with row distances of more than 200 mm. Hoeing in cereals with conventional row distances of 125–170 mm requires the development of automatic steering systems. The objective of this project was to develop a new automatic guidance system for inter-row hoeing using camera-based row detection and automatic side-shift control. Six field studies were conducted in winter wheat to investigate accuracy, weed control efficacy and crop yields of this new hoeing technology.

A three-meter prototype and a 6-meter segmented hoe were built and tested at three different speeds in 150 mm seeded winter wheat. The maximum lateral offset from the row center was 22.53 mm for the 3 m wide hoe and 18.42 mm for the 6 m wide hoe. Camera-guided hoeing resulted in 72–96% inter-row and 21–91% intra-row weed control efficacy (WCE). Weed control was 7–15% higher at 8 km h−1 compared to 4 km h−1. WCE could be increased by 14–22% when hoeing was combined with weed harrowing. Grain yields after camera-guided hoeing at 8 km h−1 were 15–76% higher than the untreated control plots and amounted the same level as the weed-free herbicide plots. The study characterizes camera-guided hoeing in cereals as a robust and effective method of weed control.
The Right Not to Know: some Steps towards a Compromise
Authors: Davies Ben , Savulescu Julian
Published: October 2020

There is an ongoing debate in medicine about whether patients have a ‘right not to know’ pertinent medical information, such as diagnoses of life-altering diseases. While this debate has employed various ethical concepts, probably the most widely-used by both defenders and detractors of the right is autonomy. Whereas defenders of the right not to know typically employ a ‘liberty’ conception of autonomy, according to which to be autonomous involves doing what one wants to do, opponents of the right not to know often employ a ‘duty’ understanding, viewing autonomy as involving an obligation to be self-governing. The central contribution of this paper is in showing that neither view of autonomy can reasonably be said to support the extreme stances on the right not to know that they are sometimes taken to. That is, neither can a liberty view properly defend a right not to know without limits, nor can a duty view form the basis of an absolute rejection of the right not to know. While there is still theoretical distance between these two approaches, we conclude that the views are considerably closer on this issue than they first appear, opening the way for a possible compromise.
Novel 500-GHz Band Waveguide Stepped Septum-Type Circular Polarizer with a New High-Accuracy and Very Small Waveguide Flange
Authors: Hasegawa Yutaka , Maezawa Hiroyuki , Ogawa Hideo
Published: October 2020

A new waveguide stepped septum-type circular polarizer (SST-CP) was developed to operate in the 500-GHz band for radio astronomical and planetary atmospheric observations. In a previous study, we developed a practical SST-CP for the 230-GHz band. However, several issues prevent this device being easily scaled down to the 500-GHz band, such as manufacturing dimensional errors and waveguide flange position errors. In this study, we developed a new waveguide flange with a high-accuracy position determination mechanism and a very small size of 10 × 10 mm. We also developed a new fabrication technique to obtain very good flatness for the device’s blank materials by high-accuracy polishing using a resin fixture. Using these new methods, the manufactured 500-GHz band SST-CP achieved a cross-polarization talk level of better than – 30 dB at 465–505 GHz, a device surface flatness of within 3 μm, and also the horizontal positioning error of ± 3 μm. These results indicate that the developed 500-GHz band SST-CP has high performance in the high-frequency band, and thus the new manufacturing methods are effective in the 500-GHz band.