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DOAJ Open Access 2026
Near infrared spectroscopy predicts crude protein concentration in hemp grain

Ryan V. Crawford, Jamie L. Crawford, Julie L. Hansen et al.

Abstract This study evaluated near‐infrared spectroscopy (NIRS) for nondestructive crude protein (CP) prediction in hemp (Cannabis sativa L.) grain and validated the biological basis of spectral predictions. Note that 149 whole grain samples from 38 cultivars were collected from New York trials (2017–2021) and validated for CP by combustion. Seven preprocessing methods were tested using 100 training/testing splits, with standard normal variate transformation following Savitzky–Golay filtering selected as optimal. Comparing algorithms showed that partial least squares regression (PLSR) significantly outperformed support vector machines and random forest. The best preprocessing method and algorithm was applied to 1000 additional splits. Optimal models contained 12 components with mean performance of root mean square error [RMSE] = 9.94, r2 = 0.84, relative predicted deviation [RPD] = 2.5, and ratio of performance to interquartile distance [RPIQ] = 3.94. More than 99% of the models had, at minimum, the ability to distinguish between high and low values, with 93.2% capable of quantitative prediction. To validate biological relevance, a protein‐focused model was developed using three known protein absorption bands (1200–1250, 1500–1550, and 2040–2090 nm). These models had substantially reduced performance with 86% of models capable of distinguishing between high and low values but only 14% of models capable of quantitative prediction. However, this targeted approach offers evidence that NIRS predictions are biologically grounded in protein‐specific spectral features rather than spurious correlations. This research demonstrates the promise and biological validity of NIRS for hemp grain CP assessment, supporting applications in breeding programs, although applications demanding more accurate prediction will require better models.

Agriculture, Environmental sciences
CrossRef Open Access 2020
Frequency-dependent dielectric constant prediction of polymers using machine learning

Lihua Chen, Chiho Kim, Rohit Batra et al.

AbstractThe dielectric constant (ϵ) is a critical parameter utilized in the design of polymeric dielectrics for energy storage capacitors, microelectronic devices, and high-voltage insulations. However, agile discovery of polymer dielectrics with desirable ϵ remains a challenge, especially for high-energy, high-temperature applications. To aid accelerated polymer dielectrics discovery, we have developed a machine-learning (ML)-based model to instantly and accurately predict the frequency-dependent ϵ of polymers with the frequency range spanning 15 orders of magnitude. Our model is trained using a dataset of 1210 experimentally measured ϵ values at different frequencies, an advanced polymer fingerprinting scheme and the Gaussian process regression algorithm. The developed ML model is utilized to predict the ϵ of synthesizable 11,000 candidate polymers across the frequency range 60–1015 Hz, with the correct inverse ϵ vs. frequency trend recovered throughout. Furthermore, using ϵ and another previously studied key design property (glass transition temperature, Tg) as screening criteria, we propose five representative polymers with desired ϵ and Tg for capacitors and microelectronic applications. This work demonstrates the use of surrogate ML models to successfully and rapidly discover polymers satisfying single or multiple property requirements for specific applications.

166 sitasi en
DOAJ Open Access 2024
Ten-day vonoprazan–amoxicillin dual therapy versus 14-day esomeprazole–amoxicillin dual therapy for first-line eradication: a prospective multicenter randomized controlled trial

Ben-Gang Zhou, Ming-Wen Guo, Li-Juan Zhang et al.

Background: The efficacy of the 14-day esomeprazole–amoxicillin (EA) dual therapy in eradicating Helicobacter pylori ( H. pylori ) has been widely discussed previously. Vonoprazan, a novel potassium-competitive acid blocker, presents rapid, potent, and long-lasting acid inhibitory effects compared to esomeprazole. However, there is currently a scarcity of direct comparisons between the 10-day vonoprazan–amoxicillin (VA) and the 14-day EA dual therapy for H. pylori eradication. Objectives: This study aimed to compare the efficacy and safety of the 10-day VA and the 14-day EA dual therapy for H. pylori first-line eradication. Design: This study was a prospective, multicenter, open-label, randomized controlled trial. Methods: The study was conducted at 10 hospitals in China. In total, 570 newly diagnosed H. pylori -infected patients were recruited from April 2023 to February 2024. These patients were randomly assigned to either the 10-day VA group (vonoprazan 20 mg twice daily + amoxicillin 1000 mg three times daily) or the 14-day EA group (esomeprazole 20 mg four times daily + amoxicillin 750 mg four times daily). The primary outcome was the eradication rate, with secondary outcomes including adverse events and compliance. Results: The 10-day VA regimen outperformed the 14-day EA regimen in terms of eradication rates in intention-to-treat (ITT) analysis (85.4% vs 76.7%, p  = 0.008), modified ITT analysis (90.7% vs 84.8%, p  = 0.036), and per-protocol (PP) analysis (91.1% versus 85.5%, p  = 0.047). The non-inferiority p -values in all three analyses were less than 0.001. No statistically significant difference was observed in the incidence of adverse events between the two groups (9.1% vs 11.7%, p  = 0.308). The 10-day VA regimen demonstrated higher compliance compared to the 14-day EA regimen ( p  = 0.006). Conclusion: The 10-day VA dual therapy showed a satisfactory eradication rate of 91.1% (PP analysis), demonstrating good safety and better compliance compared to the 14-day EA dual therapy as the first-line eradication. Trial registration: This trial was registered in the Chinese Clinical Trial Registry (registration number: ChiCTR2300070475) on April 12, 2023.

Diseases of the digestive system. Gastroenterology
DOAJ Open Access 2024
A single-item Expectancy Measure’s Validity, Reliability, and Responsiveness to Detect Changes in Clinical Efficacy Studies of Integrative Cancer Therapies: A Methodology Study

Anna Efverman PhD

Background: Expectations may modify outcomes. However, studies often fail to measure expectations. This raises the need for a brief valid and reliable expectancy measure. Objectives: To study treatment expectations in individuals entering acupuncture or rest, validity and test re-test reliability of a single-item expectancy measure graded on a category scale, a Numeric Rating Scale (NRS) and a Visual Analog Scale (VAS), and to identify psychometric differences between the scales. Method: In this methodology study, treatment expectations were measured in 363 participants before they received acupuncture (genuine traditional penetrating or non-penetrating telescopic sham acupuncture, n = 239, 98%, responded) or a control treatment involving just rest (n = 120, 100%, responded), aimed to improve level of relaxation. A treatment expectancy measure, graded on a five-grade category scale, an eight-grade NRS and a 100 mm VAS, was tested for test re-test reliability. Level of expectation and relaxation was measured at baseline, pre- and post-therapy (n = 729 expectancy measurements). Results: The participants scheduled for acupuncture or rest believed moderately (Inter Quartile Range, IQR, moderately-much) and much (IQR moderately-much) the treatment to be effective. The Intra-Class Correlation coefficient versus Kappa coefficient between test and re-test was .868/.868 for the category scale, .820/.820 for the NRS, and .856/.854 for the VAS. The middle step “Believe moderately the treatment to be effective” was equivalent with median 4 (IQR, 3-4) on NRS and median 52 mm (IQR 42-52) on VAS. The response rates were 708 (97%) on the category scale, 707 (97%) on the NRS, and 703 (96%) on the VAS. All three scales discriminated that pre-therapy expectations were more positive in the individuals who reported an improvement in relaxation level ( P < .001-.003). The VAS presented higher responsiveness to detect expectancy changes over time (71% increased expectation), compared to the NRS (52% increased) and the category scale (12% increased), P < .001. Conclusions: Individuals entering acupuncture, or a control intervention, presented positive treatment expectations, and the expectancy measure presented satisfactory reliability, validity, high response rates, sensitiveness, and responsiveness. Integrative cancer therapy researchers who want to control for expectancy-related bias in clinical trials should consider measuring expectation using the single-item expectancy measure.

Neoplasms. Tumors. Oncology. Including cancer and carcinogens
DOAJ Open Access 2022
Reproductive Biology of Female Pacific Halibut (Hippoglossus stenolepis) in the Gulf of Alaska

Teresa Fish, Teresa Fish, Nathan Wolf et al.

Developing a robust understanding of Pacific halibut reproductive biology is essential to understanding the different components (e.g. maturity) that determine the reproductive output of the species and, therefore, for estimating the relative female spawning biomass. With these, effective and proactive management strategies can be designed and implemented to face the large-scale environmental changes to which high-latitude spawning fish are particularly vulnerable. To date, reproductive studies of Pacific halibut have mainly focused on population or regional scales, leaving the specific details of organism-level reproductive development unexamined. The work described here aimed to address information gaps in Pacific halibut reproductive biology by conducting a detailed histological examination of temporal changes in ovarian development over an annual reproductive cycle with special attention to the use of biological indicators (e.g. oocyte diameter, gonadosomatic index, hepatosomatic index, Fulton’s condition factor, somatic fat) in characterizing female developmental stages and reproductive phases. Our results provide a foundation for future studies directed at improving current maturity estimations by histological assessment and explore models that test the utility of biological indicators to predict maturity in this important fish species.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2021
miRNA-mediated loss of m6A increases nascent translation in glioblastoma.

John P Zepecki, David Karambizi, J Eduardo Fajardo et al.

Within the glioblastoma cellular niche, glioma stem cells (GSCs) can give rise to differentiated glioma cells (DGCs) and, when necessary, DGCs can reciprocally give rise to GSCs to maintain the cellular equilibrium necessary for optimal tumor growth. Here, using ribosome profiling, transcriptome and m6A RNA sequencing, we show that GSCs from patients with different subtypes of glioblastoma share a set of transcripts, which exhibit a pattern of m6A loss and increased protein translation during differentiation. The target sequences of a group of miRNAs overlap the canonical RRACH m6A motifs of these transcripts, many of which confer a survival advantage in glioblastoma. Ectopic expression of the RRACH-binding miR-145 induces loss of m6A, formation of FTO/AGO1/ILF3/miR-145 complexes on a clinically relevant tumor suppressor gene (CLIP3) and significant increase in its nascent translation. Inhibition of miR-145 maintains RRACH m6A levels of CLIP3 and inhibits its nascent translation. This study highlights a critical role of miRNAs in assembling complexes for m6A demethylation and induction of protein translation during GSC state transition.

DOAJ Open Access 2021
Optimization of Communication Schemes for DMA-Controlled Accelerators

Jooho Wang, Sungkyung Park, Chester Sungchung Park

The hardware accelerator controlled by direct memory access (DMA) is greatly influenced by the communication bandwidth from/to DRAM through on-chip buses. This paper proposes a novel performance estimation algorithm to optimize the communication schemes (CSs), which are defined by the number of direct memory access controllers (DMACs) and the bank allocation of DRAM. In order to facilitate the optimization of CSs, a communication primitive (CP) is defined by the bank allocation and the set of activated DMACs. By using the communication bandwidths of CPs obtained from prior full-system simulations, the proposed performance estimation algorithm can predict the communication performance of CSs more accurately, compared with the conventional performance estimation algorithms. When it is applied to convolutional neural networks (CNNs) and wireless communications (LDPC-coded MIMO-OFDM), the estimation error is measured to be no more than 6.4&#x0025; and 5&#x0025;, respectively. In addition, compared with the conventional simulation-based approaches, the proposed estimation algorithm provides a speedup of two orders of magnitudes. The proposed performance estimation algorithm is used to optimize the CS of the CNNs and explore a design space characterized by bank interleaving, outstanding transactions, layer shape, tile size, and hardware frequency. It is shown that the optimized CS improves communication performance by up to 68&#x0025; for the third convolutional layers of AlexNet and 60&#x0025; for the MIMO of LDPC-coded MIMO-OFDM. In addition, the DRAM latency is minimized by setting the bank interleaving to the number of outstanding transactions. Moreover, the simulation results show that the optimum CS depends on the application. It is also shown that the use of an extra DMAC does not necessarily improve the communication performance.

Electrical engineering. Electronics. Nuclear engineering
DOAJ Open Access 2017
Identification of a large, fast-expanding HIV-1 subtype B transmission cluster among MSM in Valencia, Spain.

Juan Ángel Patiño-Galindo, Manoli Torres-Puente, María Alma Bracho et al.

We describe and characterize an exceptionally large HIV-1 subtype B transmission cluster occurring in the Comunidad Valenciana (CV, Spain). A total of 1806 HIV-1 protease-reverse transcriptase (PR/RT) sequences from different patients were obtained in the CV between 2004 and 2014. After subtyping and generating a phylogenetic tree with additional HIV-1 subtype B sequences, a very large transmission cluster which included almost exclusively sequences from the CV was detected (n = 143 patients). This cluster was then validated and characterized with further maximum-likelihood phylogenetic analyses and Bayesian coalescent reconstructions. With these analyses, the CV cluster was delimited to 113 patients, predominately men who have sex with men (MSM). Although it was significantly located in the city of Valencia (n = 105), phylogenetic analyses suggested this cluster derives from a larger HIV lineage affecting other Spanish localities (n = 194). Coalescent analyses estimated its expansion in Valencia to have started between 1998 and 2004. From 2004 to 2009, members of this cluster represented only 1.46% of the HIV-1 subtype B samples studied in Valencia (n = 5/143), whereas from 2010 onwards its prevalence raised to 12.64% (n = 100/791). In conclusion, we have detected a very large transmission cluster in the CV where it has experienced a very fast growth in the recent years in the city of Valencia, thus contributing significantly to the HIV epidemic in this locality. Its transmission efficiency evidences shortcomings in HIV control measures in Spain and particularly in Valencia.

Medicine, Science
DOAJ Open Access 2017
Hepatocellular carcinoma: Implications for Asia-Pacific Oncology Nurses

Deborah A Boyle

Hepatocellular carcinoma (HCC) is a prominent malignancy in the Asia-Pacific region. Despite considerable knowledge about it's scope and nature this malignancy remains incurable. This manuscript reviews the epidemiology of this cancer, its pathogenesis, risk factors, potential prevention, surveillance, treatment, and the oncology nurses' role relative to this malignancy. A literature search from the past decade was performed using the PubMed and CINAHL databases using the search terms “hepatocellular carcinoma,” “Asia,” and “nursing issues”. Themes such as etiology, prevention, treatment, and prognosis were included in this synthesis which has particular relevance to oncology nurses within the Asia-Pacific region.

Neoplasms. Tumors. Oncology. Including cancer and carcinogens, Nursing
DOAJ Open Access 2017
Management of Peripheral and Truncal Venous Injuries

Triantafillos G. Giannakopoulos, Efthymios D. Avgerinos

Civilian injuries are increasing according to the World Health Organization, and this is attributed mainly to road traffic accidents and urban interpersonal violence. Vascular injuries are common in these scenarios and are associated with high morbidity and mortality rates. Associated peripheral venous trauma is less likely to lead to death and controversy remains whether ligation or repair should be the primary approach. Conversely, non-compressible truncal venous insult can be lethal due to exsanguination, thus a high index of suspicion is crucial. Operative management is demanding with fair results but recent endovascular adjuncts demonstrate promising results and seem to be the way forward for these serious conditions.

DOAJ Open Access 2016
Optimizing Your Mentoring Relationship: A Toolkit for Mentors and Mentees

Megan Aylor, Mario Cruz, Aditee Narayan et al.

Abstract Introduction Mentorship is a vital component of academic and professional development. Mentees report positive impacts from mentorship programs, yet institutions and societies may struggle to meet their mentees’ needs due to factors such as mentor fatigue and lack of mentor training. To address this in our own professional society, the Association of Pediatric Program Directors, we developed a mentor toolkit in order to utilize a variety of mentoring models, provide faculty development for midlevel mentors, and offer guidance to mentees. Methods Most of these tools were designed to be administered in an interactive format such as a workshop or seminar with think-pair-share opportunities. The toolkit begins by providing a definition of mentoring and reinforcing the benefits and the characteristics of effective mentoring relationships. Next, we discuss the important role that mentees have in creating and maintaining effective mentoring relationships (i.e., mentee-driven mentoring). We then introduce a mentoring mosaic activity designed to help mentees examine their professional network and think about how they might expand it to fulfill the spectrum of their mentoring needs. Next, we present guidelines for the implementation of four mentoring models that can be used within one's institution: traditional dyadic mentoring, peer group mentoring, meet the professor mentoring, and speed mentoring. We then provide tools that can be used to help facilitate effective mentoring development. Results This toolkit has successfully served as a self-guided resource at national meetings for many years, garnering positive feedback from mentors and mentees alike. Discussion The principles and methods are easily generalizable and may be used to guide mentorship programs within institutional and professional societies, as well as to assist mentors and mentees in optimizing their individual mentoring relationships.

Medicine (General), Education
DOAJ Open Access 2015
Associations of Bone Mineral Density with Lean Mass, Fat Mass, and Dietary Patterns in Postmenopausal Chinese Women: A 2-Year Prospective Study.

Yongjie Chen, Jing Xiang, Zhiqiang Wang et al.

To assess factors associated with bone mineral density (BMD) in postmenopausal women in a longitudinal study, and to examine the relative contribution of lean mass, fat mass, dietary patterns, and years since menopause to BMD.Two hundred and eighty-two postmenopausal women were randomly selected from Hongqi Community Health Center, in Harbin City, China. All participants were followed up from 2009 to 2011. Dietary data were collected using a Food Frequency Questionnaire. BMD of the left hip, the lumbar spine, and the total body, and the body composition were measured by dual-energy X-ray absorptiometry at baseline and follow-up.Lean mass and fat mass were positively associated with BMD of the spine, hip, and the total body at both baseline and follow-up. The association between fat mass and BMD at the spine at baseline (P = 0.210) and at the spine (P = 0.116) and hip (P = 0.073) in the second year was not statistically significant when height was adjusted. Six dietary patterns were identified but only cereal grains-fruits pattern (P = 0.001 in the spine, P = 0.037 in hip) and milk-root vegetables pattern (P = 0.010 in hip) were associated with BMD of the spine and hip. The linear mixed model of follow-up data showed that lean mass, years since menopause, and age of menophania were the significant determinants of BMD of all sites. Moreover, lean mass was the best determinant of BMD (VIP = 1.936).Lean mass, years since menopause, age of menophania and dietary patterns are the important determinants of BMD of the spine, hip, and the total body. Lean mass is the best determinant of BMD.

Medicine, Science
DOAJ Open Access 2013
Temperature induced syllable breaking unveils nonlinearly interacting timescales in birdsong motor pathway.

Matías A Goldin, Leandro M Alonso, Jorge A Alliende et al.

The nature of telencephalic control over premotor and motor circuits is debated. Hypotheses range from complete usurping of downstream circuitry to highly interactive mechanisms of control. We show theoretically and experimentally, that telencephalic song motor control in canaries is consistent with a highly interactive strategy. As predicted from a theoretical model of respiratory control, mild cooling of a forebrain nucleus (HVC) led to song stretching, but further cooling caused progressive restructuring of song, consistent with the hypothesis that respiratory gestures are subharmonic responses to a timescale present in the output of HVC. This interaction between a life-sustaining motor function (respiration) and telencephalic song motor control suggests a more general mechanism of how nonlinear integration of evolutionarily new brain structures into existing circuitry gives rise to diverse, new behavior.

Medicine, Science
DOAJ Open Access 2013
Neglecting rice milling yield and quality underestimates economic losses from high-temperature stress.

Nathaniel B Lyman, Krishna S V Jagadish, L Lanier Nalley et al.

Future increases in global surface temperature threaten those worldwide who depend on rice production for their livelihoods and food security. Past analyses of high-temperature stress on rice production have focused on paddy yield and have failed to account for the detrimental impact of high temperatures on milling quality outcomes, which ultimately determine edible (marketable) rice yield and market value. Using genotype specific rice yield and milling quality data on six common rice varieties from Arkansas, USA, combined with on-site, half-hourly and daily temperature observations, we show a nonlinear effect of high-temperature stress exposure on yield and milling quality. A 1 °C increase in average growing season temperature reduces paddy yield by 6.2%, total milled rice yield by 7.1% to 8.0%, head rice yield by 9.0% to 13.8%, and total milling revenue by 8.1% to 11.0%, across genotypes. Our results indicate that failure to account for changes in milling quality leads to understatement of the impacts of high temperatures on rice production outcomes. These dramatic losses result from reduced paddy yield and increased percentages of chalky and broken kernels, which together decrease the quantity and market value of milled rice. Recently published estimates show paddy yield reductions of up to 10% across the major rice-producing regions of South and Southeast Asia due to rising temperatures. The results of our study suggest that the often-cited 10% figure underestimates the economic implications of climate change for rice producers, thus potentially threatening future food security for global rice producers and consumers.

Medicine, Science
DOAJ Open Access 2012
Uncoupling the effects of seed predation and seed dispersal by granivorous ants on plant population dynamics.

Xavier Arnan, Roberto Molowny-Horas, Anselm Rodrigo et al.

Secondary seed dispersal is an important plant-animal interaction, which is central to understanding plant population and community dynamics. Very little information is still available on the effects of dispersal on plant demography and, particularly, for ant-seed dispersal interactions. As many other interactions, seed dispersal by animals involves costs (seed predation) and benefits (seed dispersal), the balance of which determines the outcome of the interaction. Separate quantification of each of them is essential in order to understand the effects of this interaction. To address this issue, we have successfully separated and analyzed the costs and benefits of seed dispersal by seed-harvesting ants on the plant population dynamics of three shrub species with different traits. To that aim a stochastic, spatially-explicit individually-based simulation model has been implemented based on actual data sets. The results from our simulation model agree with theoretical models of plant response dependent on seed dispersal, for one plant species, and ant-mediated seed predation, for another one. In these cases, model predictions were close to the observed values at field. Nonetheless, these ecological processes did not affect in anyway a third species, for which the model predictions were far from the observed values. This indicates that the balance between costs and benefits associated to secondary seed dispersal is clearly related to specific traits. This study is one of the first works that analyze tradeoffs of secondary seed dispersal on plant population dynamics, by disentangling the effects of related costs and benefits. We suggest analyzing the effects of interactions on population dynamics as opposed to merely analyzing the partners and their interaction strength.

Medicine, Science

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