bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment patterns and survival in patients with early‐onset pancreatic cancer
Authors: Saadat Lily V. , Chou Joanne F. , Gonen Mithat , Soares Kevin C. , Kingham T. Peter , Varghese Anna M. , Jarnagin William R. , D’Angelica Michael I. , Drebin Jeffrey A. , O’Reilly Eileen M. , Wei Alice C.
Published: July 2021

Background

Pancreatic cancer is uncommon in patients younger than 50 years, although its incidence is increasing. This study characterizes treatment utilization for early‐onset pancreatic cancer (EOPC) versus average‐age‐onset pancreatic cancer (AOPC) and identifies factors associated with failure to receive treatment.

Methods

The National Cancer Data Base (NCDB) was queried for patients with EOPC (age < 50 years) or AOPC (age ≥ 50 years) from 2004 to 2016. Multinomial regression was used to compare utilization (single modality vs multimodal treatment with or without surgery vs no treatment) between EOPC and AOPC. Kaplan‐Meier methods were used to estimate overall survival (OS).

Results

Of 248,634 patients, 15,710 (6.3%) had EOPC. There were more male patients (56% vs 50%), non‐White patients, and privately insured patients (61% vs 30%) with EOPC versus AOPC, without notable differences in clinical stage distribution. Patients with EOPC received more chemotherapy (38% vs 29%), surgery (9% vs 6.9%), chemoradiation (12% vs 9.2%), and multimodal treatment (21% vs 15%). The odds of receiving multimodal curative therapy were significantly higher for patients with EOPC versus patients with AOPC after adjustments for confounders (odds ratio, 3.89; 95% confidence interval [CI], 3.66‐4.15; P < .001). Nineteen percent of patients with EOPC, in contrast to 39% of patients with AOPC, received no treatment. Patients with AOPC more frequently declined chemotherapy (15% vs 9.5%). One‐year OS was higher for EOPC versus AOPC across each stage (0/I/II, 72% [95% CI, 71%‐74%] vs 53% [95% CI, 53%‐54%]; III, 48% [95% CI, 45%‐50%] vs 38% [95% CI, 37%‐38%]; IV, 25% [95% CI, 24%‐26%] vs 15% [95% CI, 15%‐15%]) and treated patients (0/I/II, 75% [95% CI, 74%‐77%] vs 64% [95% CI, 63%‐64%]; III, 51% [95% CI, 49%‐54%] vs 47% [95% CI, 47%‐48%]; IV, 29% [95% CI, 28%‐31%] vs 23% [95% CI, 23%‐24%]).

Conclusions

Patients with EOPC receive more oncologic therapy than patients with AOPC, although the intensity, type, and duration of chemotherapy are not available in the NCDB; however, 19% and 39%, respectively, receive no therapy. Underutilization may explain suboptimal oncologic outcomes. Efforts to improve access and treatment utilization in all age groups are warranted.
Attachment anxiety as mediator of the relationship between childhood trauma and personality dysfunction in borderline personality disorder
Authors: Erkoreka Leire , Zamalloa Iker , Rodriguez Santiago , Muñoz Pedro , Mendizabal Imanol , Zamalloa M. Isabel , Arrue Aurora , Zumarraga Mercedes , Gonzalez‐Torres Miguel Angel
Published: July 2021

Insecure attachment has been described as mediating the relationship between childhood trauma and dysfunctional personality traits in different mental disorders. Despite the role insecure attachment and childhood trauma have independently demonstrated to play as determinants of borderline personality disorder, less is known about the mediating mechanisms explaining these associations. For the first time, we assessed adult attachment, childhood trauma and dimensional personality pathology in a sample of outpatients with borderline personality disorder and tested whether the association between childhood trauma and personality dysfunction was at least partially attributable to insecure attachment. The results showed that attachment anxiety fully mediated the relationship between specific types of trauma (emotional abuse and physical neglect) and emotional dysregulation. Further, emotional abuse was both directly associated with dissocial behaviour and indirectly via attachment anxiety (partial mediation). Emotional abuse has been described as an essential environmental factor for the development of borderline personality disorder and emotional dysregulation, on its part, as the core feature of the condition. Our results indicate that attachment anxiety explains the link between these central aspects of borderline personality disorder. Our findings are consistent with previous research and current etiological understanding of the condition and provide support for recommending a careful assessment of childhood traumatic experiences and adult attachment style to gain a more comprehensive insight into the symptoms and its heterogeneity. As a secondary aim, we assessed the effect parental mental illness may have in these mediation models, but no significant influence on childhood trauma, attachment or personality was found.
Economic Impact of Prohexadione Calcium for Managing Vine Growth in Runner Market‐Type Peanut
Authors: Monfort W. Scott , Tubbs R. Scott
Published: July 2021

In recent years, there have been several new peanut varieties developed that perform exceptionally well across many environments and have improved disease resistance packages. However, growers have been slow to adopt some new varieties due to their excessive vine growth. One potential solution is to use a plant growth regulator to manage the excessive vine growth. Earn 0.5 CEUs in Crop Management by reading this article and taking the quiz at www.certifiedcropadviser.org/education/classroom/classes/995.
Time‐course changes in the ionomic profiles of rice leaves and their application in growth stage prediction
Authors: Miyamoto‐Maeta Miho , Kamiya Takehiro , Fujiwara Toru , Hirotomi Dai , Iwata Hiroyoshi
Published: July 2021

Ionomic profiling of plant tissues aims to understand the role of genetic factors and external conditions in mineral nutrient composition. However, little is known about the time‐course changes occurring in these profiles during plant growth. The influences of genotype, environment, and management factors are not well understood. To clarify the variation in time‐course data and to identify factors influencing these changes, we analyzed the ionomic leaf profiles of nine rice (Oryza sativa L.) cultivars, from transplantation to harvest, under different environmental conditions. An ANOVA was conducted separately for each element to elucidate the main effects of cultivar, fertilization, and growth stage, which were highly significant for all the elements observed except fertilization. The growth stage was the most significant for all elements except B. Conversely, the fertilization effect was not significant in half of the elements studied (Li, B, Na, Mg, P, S, K, Ca, and Cd). The elements during the growth stage were relatively stable across the environments and cultivars studied. To investigate the relationship between the changing pattern and the growth stage, we predicted the growth stage of rice based on the ionomic profile leaves using a machine learning model. Over 80% of the plants in this study were correctly classified into their growth stages with 10‐fold cross‐validation using the random forest model, with a highly significant contribution of the essential macronutrients P, Ca, S, Mg, and K as explanatory variables, indicating that they could be important indicators of the growth stage of rice plants.
Investor behavior and the demand for conventional and socially responsible mutual funds
Authors: Matallín‐Sáez Juan Carlos , Soler‐Domínguez Amparo , Navarro‐Montoliu Salvador , de Mingo‐López Diego Víctor
Published: July 2021

This study analyzes the demand for conventional and socially responsible (SR) mutual funds using cash flow data from a large sample of U.S. equity funds. For both types of funds, previous results have a positive impact on inflows. However, redemptions' behavior differs. Outflows correlate negatively with past results in conventional portfolios, whereas this relationship is positive for SR funds: investors are more likely to redeem shares in the best‐performing funds while holding funds that performed poorly. This behavior is compatible with a disposition effect in SR funds. These results hold even after controlling for other variables driving mutual fund demand. Hence, inflows and outflows of conventional funds were found to be positively related to past idiosyncratic risk, expenses and turnover, but negatively related to size and age. For SR funds, these relationships are stronger for size and idiosyncratic risk, and take the opposite sign for age, expenses and turnover.
Reconstructed Bismuth‐Based Metal−Organic Framework Nanofibers for Selective CO2‐to‐Formate Conversion: Morphology Engineering
Authors: Ying Yulong , Khezri Bahareh , Kosina Jiri , Pumera Martin
Published: July 2021

Electrochemical reduction of carbon dioxide (ERCO2) is an attractive and sustainable approach to close the carbon loop. Formic acid is a high‐value and readily collectible liquid product. However, the current reaction selectivity remains unsatisfactory. In this study, the bismuth‐containing metal−organic framework CAU‐17, with morphological variants of hexagonal prisms (CAU‐17‐hp) and nanofibers (CAU‐17‐fiber), is prepared at room temperature through a wet‐chemical approach and employed as the electrocatalyst for highly selective CO2‐to‐formate conversion. An H3BTC‐mediated morphology reconstruction is systematically investigated and further used to build a CAU‐17‐fiber hierarchical structure. The as‐prepared CAU‐17‐fiber_400 electrodes give the best electrocatalytic performance in selective and efficient formate production with FEHCOO− of 96.4 % and jCOOH− of 20.4 mA cm−2 at −0.9 VRHE. This work provides a new mild approach for synthesis and morphology engineering of CAU‐17 and demonstrates the efficacy of morphology engineering in regulating the accessible surface area and promoting the activity of MOF‐based materials for ERCO2.
Energy‐efficient framework for throughput enhancement of cognitive radio network
Authors: Bala Indu , Ahuja Kiran
Published: July 2021

Recently, cognitive radio (CR) has evolved as a next‐generation communication technology that has the potential to use the radio frequency (RF) spectrum in most efficient manner as compared to the other existing cellular communication technologies. The performance of CR system largely depends upon the accuracy of the sensing results. However, the sensing ambiguities such as false alarm and miss detection cause spectrum underutilization and severe interference to the primary user (PU), respectively. In this paper, both issues are addressed by modifying the conventional frame structure by introducing two sensing slots along with a transmission slot to overcome sensing ambiguities. For the targeted probability of detection, the first sensing slot is kept small and fixed, and sensing results are stored in a flag bit up to that duration. The second sensing slot (optional) is used whenever the flag bit status varies in the current frame from the previous frame. Considering sensing throughput trade‐off issue of CR, the second sensing slot is optimized to enhance the effective throughput and energy efficiency of the secondary communication system. The simulation results are presented to validate the effectiveness of the proposed scheme with a modified frame structure, which is capable to achieve 65% higher energy efficiency than the conventional scheme when PU is present in a channel, that is, P(H1) = 1.
Antibacterial and anti‐inflammatory activity of valproic acid‐pyrazole conjugates as a potential agent against periodontitis
Authors: Dong Lei , Fang Ling , Dai Xinxiang , Zhang Jia , Wang Jia , Xu Pei
Published: July 2021

Periodontitis is a serious global concern. Therefore, in the present study, we intend to synthesize novel valproic‐acid pyrazole conjugates as a novel agent against periodontitis. The molecules were developed in a facile synthetic route and obtained in excellent yields. The entire set of molecules were screened for antibacterial activity against a battery of micro‐organisms responsible for periodontitis such as P. gingivalis, P. intermedia, F. nucleatum, and E. coli, where they exhibit considerable inhibitory activity. The most potent compound among the tested series, compound 7c showed bactericidal activity in the time‐kill curve against E. coli. Compound 7c also showed inhibition of NF‐ĸB transcriptional activity in LPS‐stimulated RAW264.7 cells with IC50 of 19.23 μM. The effect of compound 7c was also investigated in experimentally induced periodontitis in rats on various indices of oxidative stress (MDA, SOD, and GSH), inflammation (TNF‐α, IL‐1β, and IL‐6), and apoptosis. It has been found that compound 7c significantly inhibits oxidative stress, inflammation, and apoptosis in a dose‐dependent manner. Compound 7c also inhibits the expression of COX‐2 and iNOS as shown by western blot analysis.
Transcriptional response of mushrooms to artificial sun exposure
Authors: Krah Franz‐Sebastian , Hess Jaqueline , Hennicke Florian , Kar Ritwika , Bässler Claus
Published: July 2021

Climate change causes increased tree mortality leading to canopy loss and thus sun‐exposed forest floors. Sun exposure creates extreme temperatures and radiation, with potentially more drastic effects on forest organisms than the current increase in mean temperature. Such conditions might potentially negatively affect the maturation of mushrooms of forest fungi. A failure of reaching maturation would mean no sexual spore release and, thus, entail a loss of genetic diversity. However, we currently have a limited understanding of the quality and quantity of mushroom‐specific molecular responses caused by sun exposure. Thus, to understand the short‐term responses toward enhanced sun exposure, we exposed mushrooms of the wood‐inhabiting forest speciesLentinula edodes,while still attached to their mycelium and substrate, to artificial solar light (ca. 30°C and 100,000 lux) for 5, 30, and 60 min. We found significant differentially expressed genes at 30 and 60 min. Eukaryotic Orthologous Groups (KOG) class enrichment pointed to defense mechanisms. The 20 most significant differentially expressed genes showed the expression of heat‐shock proteins, an important family of proteins under heat stress. Although preliminary, our results suggest mushroom‐specific molecular responses to tolerate enhanced sun exposure as expected under climate change. Whether mushroom‐specific molecular responses are able to maintain fungal fitness under opening forest canopies remains to be tested.
A stochastic model of epilithic algal succession and patch dynamics in streams
Authors: DeNicola Dean M. , McNair James N. , Suh Jiyeon
Published: July 2021

Explaining spatiotemporal variability in metacommunities is challenging because conducting empirical studies that link mechanisms across scales is difficult. We developed a stochastic model of epilithic algal succession in streams to better understand the underlying interactions that drive patch dynamics at three levels of spatial hierarchy: patch, channel habitat, and reach. The state of an algal patch is specified by one of nine community types, which are defined by growth form. Ninety‐two empirical data sets of epilithic succession were used to estimate Markov transition probabilities among patch types as functions of inputs for light, nutrients, and current. Two additional probability matrices determine the effects of herbivory and disturbance based on user inputs. Testing model predictions of patch composition against independent empirical data indicated good correspondence based on resemblance metrics. Early in succession, most patches were occupied by prostrate and erect diatoms. These persisted under low light and nutrient conditions. Motile and stalked diatom patches characterized later stages when resources were moderate. Succession proceeded to mostly filamentous green algal patches under high resource levels. Sensitivity simulations indicated light most affected succession. Herbivory and disturbance increased the probability of prostrate diatom patches. We then used the model to examine how changes in abiotic and biotic parameters affect patch dynamics at different scales. Changes in nutrients or light affected patch diversity differently at the habitat vs. reach scale. Interactions with local resource levels within a channel habitat determined its alpha diversity. The proportion of channel habitat types within a reach, and their collective response to changes, determined beta diversity. Patch diversity within channel habitats generated by herbivory followed the predation hypothesis only when nutrients were low. At the reach scale, herbivory always increased patch similarity among channel habitats, lowering beta diversity. Diversity within channel habitats followed the intermediate disturbance hypothesis for a variety of habitats. Effects of disturbance on beta diversity at the reach scale depended on channel habitat heterogeneity. The stability of patches at the reach scale was highest when disturbance created high patch diversity, supporting the insurance hypothesis. The ideas generated can improve stream bioassessment methods and provide insight into mechanisms underlying patch dynamics in other ecosystems.
Divergent responses to permafrost and precipitation reveal mechanisms for the spatial variation of two sympatric spruce
Authors: Nicklen E. Fleur , Roland Carl A. , Ruess Roger W. , Scharnweber Tobias , Wilmking Martin
Published: July 2021

The ranges of black and white spruce are largely sympatric, suggesting both species have similar climate requirements. The two species, however, are highly segregated across the landscape with black spruce most common on nutrient‐poor sites with cold, poorly drained soils and white spruce more common on productive sites with warmer, well‐drained soils. Because site conditions influence tree climate–growth responses, it is difficult to compare white and black spruce climate–growth responses as these responses are confounded by the differences in site conditions in which the two species naturally occur. As the climate warms dramatically in northern latitudes, it is critical to understand how a changing climate and associated changes in permafrost and fire regimes will interact to shape future species composition and ecosystem functioning in the boreal forest. In this study, we examined the climate–growth responses of black and white spruce growing in the same sites. This approach eliminates the confounding factor of site conditions and facilitates our understanding of how these two species respond to climate. We included standardized thaw depth of the active layer in our analysis as a representation of permafrost, which is a key factor delineating these two species' habitat preferences and is actively warming and thawing as the climate warms. Our most important finding was that the climate–growth responses of the two species, but especially white spruce, hinged on the thaw depth of the active layer. Specifically, with increasing June–July temperatures white spruce radial growth increased in areas with deep thaw or no near‐surface permafrost, but strongly decreased when growing in areas with near‐surface permafrost. Black spruce radial growth was less sensitive to June–July temperature than white spruce but had a consistent and more positive response to summer precipitation. These findings point to a primary mechanism potentially driving the positioning of these two tree species within the landscapes of boreal interior Alaska and imply widespread thawing of permafrost may foster expansion of white spruce in this region at the expense of black spruce, but that in a wetter climate, black spruce may gain competitive advantage over white spruce in some landscape positions.
Maximizing ecosystem services to the oil crop Brassica carinata through landscape heterogeneity and arthropod diversity
Authors: Stiles Shane , Lundgren Jonathan G. , Fenster Charles B. , Nottebrock Henning
Published: July 2021

To increase the resilience of our food system, we must better understand how ecosystem services such as pest control and pollination provided by a diverse insect community contribute to crop yield. We examined how landscape heterogeneity relates to insect and pollinator diversity, and how insect and pollinator diversity relates to yield of Brassica carinata, a new biofuel crop within common farming practices. Over two years, we planted 35 × 1 acre sites in a roughly 1000‐km2 area near Brookings, South Dakota, in the Prairie Coteau. We randomly assigned each site to a combination of three common farming practices: tilling (yes/no), added honey bee hives (yes/no), and treatment with systemic neonicotinoids (yes/no). Insect and pollinator diversity and the heterogeneity of the surrounding landscape at multiple spatial scales were calculated. We observed a significant positive relationship between insect (and pollinator) diversity and yield when fields were untreated, without hives, nor seed treatments. All farming practices within this study increase yield. However, farming practices alter the relationship between yield and insect (and pollinator) diversity. The addition of seed treatment or tillage negates the relationship between insect (and pollinator) diversity with yield. There was no relationship between seed treatment, diversity, and yield for all insects, and the application of seed treatment resulted in lower pollinator diversity. Increased landscape heterogeneity was correlated with more insect diversity at the 1000‐m scale and pollinator diversity at the 3000‐m scale. Our results show that increasing large‐scale landscape heterogeneity increases insect diversity, which serves as a substitute for common farming practices such as application of pesticides, tilling, or bee hives. Increased landscape heterogeneity could increase farmers' net profitability by replacing input costs associated with tillage and seed treatments.
Pest consumption by generalist arthropod predators increases with crop stage in both organic and conventional farms
Authors: Hsu Gen‐Chang , Ou Jia‐Ang , Ho Chuan‐Kai
Published: July 2021

Biocontrol agents are critical for pest management in sustainable agriculture. Generalist arthropod predators may hold a great potential as biocontrol agents because they are ubiquitous and consume pests in agroecosystems. However, their diet composition over the entire crop season has rarely been quantified, which hinders our ability to assess their biocontrol potential in real field conditions that foster temporal dynamics of pest and alternative prey populations. To fill this knowledge gap, we surveyed arthropod communities over crop stages in organic and conventional rice farms (n = 7 each) and used stable isotope analysis (δ13C and δ15N) to quantify the diet composition of generalist arthropod predators over time. We aimed to (1) examine the resource partitioning (trophic niches) in these predators, (2) quantify these predators’ diet composition from potential prey sources (rice herbivores, tourist herbivores, and detritivores), and (3) investigate the effects of farm type (organic/conventional) and crop stage (tillering/flowering/ripening stage) on pest (rice herbivore) consumption by the predators. The results show that generalist predators in both organic and conventional farms shifted trophic niches over the crop season and consumed a higher percentage of rice herbivores at late than at early crop stages (e.g., 90–93% at ripening vs. 34–55% at tillering), suggesting an increasing biocontrol value over time regardless of farm type. Surprisingly, generalist predators consumed higher proportions of rice herbivores in conventional than organic farms at tillering and flowering stages, highlighting their underappreciated potential as biocontrol agents in conventional farms. These results demonstrate that although generalist arthropod predators do consume non‐pest alternative prey, they have a high biocontrol potential (per capita pest consumption) in both organic and conventional rice farms. We encourage modern agriculture to develop techniques to support robust populations of these predators and the ecosystem services that they provide.
One‐Pot Synthesis of α‐Amino Nitrile Units through Alkylative Strecker Cyanation from Formamides
Authors: Yu Bao , Bodinier Florent , Saague‐Tenefo Maximiliene , Gerardo Patrice , Ardisson Janick , Lannou Marie‐Isabelle , Sorin Geoffroy
Published: July 2021

In this work, we describe the one‐pot synthesis of α‐amino nitrile units by the concomitant addition of alkyl (or aryl) Grignard reagents and TMS cyanide through alkylative Strecker cyanation from readily available formamides. The reaction is broad in scope and the conditions are mild, inexpensive, and easy to set‐up, providing numerous α‐amino nitriles in good yields (34 examples, 41–94 % yield).
Diastereodivergent 1,3‐Dipolar Cycloaddition of α‐Fluoro‐α,β‐Unsaturated Arylketones and Azomethine Ylides: Experimental and Theoretical DFT Studies
Authors: Jyoti Kalita Subarna , Zhao Zhen‐Ni , Li Zi‐Han , Cheng Feng , Zhao Yan , Huang Yi‐Yong
Published: July 2021

1,3‐Dipolar cycloaddition of α‐fluoro‐α,β‐unsaturated arylketones and azomethine ylides has been experimentally and theoretically investigated. The reaction proceeded in a diastereodivergent fashion: in contrast to our previous results where exo‐adducts were obtained under Cu(II) catalysis, herein we have achieved the endo‐selective 1,3‐dipolar cycloaddition using Ag(I) catalyst. Theoretical DFT calculations have been performed to understand the origin of diastereoselectivity switch, possible mechanism, and geometrical features of organometallic intermediates of both catalytic processes. The free‐energy profiles suggested that the Michael addition step is the rate determining step, and the coordination between silver atom and carbonyl oxygen atom of enone is the driving force behind endo‐selectivity.
Development of a Novel Silver‐based Sensing Platform for Detecting Superoxide Anion Released from HeLa Cells Directly
Authors: Fan Weizhou , Liu Xiaohong , Wu Jinsheng , Liu Qian , Ding Lan , Liu Xiuhui
Published: July 2021

Reactive oxygen species (ROS) have become the focus of research in recent years because they are closely related to many diseases, including cancer. Therefore, detection of ROS released from cells is of particular importance. In this work, the nanocomposites with uniform dispersion of silver nanoparticles were obtained through pyrolyzing a novel silver‐based metal‐organic framework. As the main active component of the composition, AgNPs can effectively catalyze the decomposition of hydrogen peroxide produced by superoxide anion (O2⋅−) disproportionation. Then, we designed a superoxide anion sensor (AgNPs@C/GCE) using the above nanocomposite for the first time. The prepared sensor presented excellent catalytic ability and satisfactory detection performance towards O2⋅− with a detection range as wide as eight orders of magnitude and a lower detection limit of 1.011×10−13 M (S/N=3). Furthermore, the sensor can directly measure O2⋅− released by human cervical cancer cells (HeLa) under both the normal condition and the inducement by malonic acid. In addition, we explored the effects of different concentrations of stimuli on cells. The results illustrated the high dose malonic acid can cause oxidative stress on cells. Thus, this work has the tremendous potential applications to diagnosis of diseases related to ROS.
Shake‐table test of a two‐storey low‐damage concrete wall building
Authors: Henry Richard S. , Zhou Ying , Lu Yiqiu , Rodgers Geoffrey W. , Gu Anqi , Elwood Kenneth J. , Yang Tony Y.
Published: July 2021

The increasing need to reduce damage and downtime in modern buildings has led to the development of a low‐damage design philosophy, where the earthquake loads can be resisted with damage confined to easily replaceable components. Post‐tensioned (PT) concrete walls have emerged as a popular low‐damage structural system that have been implemented in a range of buildings. In order to provide essential evidence to support the development of low‐damage concrete structures, a system‐level shake‐table test was conducted on a two‐storey low‐damage concrete wall building implementing state‐of‐art design concepts. The test building included PT rocking walls that provide the primary lateral‐load resistance in both directions, a frame that utilized slotted beam connections, and a range of alternative energy dissipation devices that were installed at wall base or/and beam‐column joints. The building was subjected to 39 tests with a range of intensity ground motions, incorporating both unidirectional and bidirectional ground motions on the structure with different combinations of wall strength and energy dissipating devices. The building performed exceptionally well during the intense series of tests, confirming the suitability of both the design methods and the connection detailing implemented. The building achieved an immediate occupancy performance objective even when subjected to maximum considered earthquake hazard shaking. The building exhibited only minor damage at the conclusion of testing, with distributed cracking in the floors and cosmetic spalling in the wall toes that did not compromise structural capacity or integrity and could be easily repaired with minimal disruption. The test has provided a rich dataset that is available for further analysis of the building response and validation of design methods and numerical models.
Effects of geometrical nonlinearity on the performance of bidirectional tuned mass dampers
Authors: Rezazadeh Hassan , Amini Fereidoun , Dogani Aghcheghloo Parichehr , Khansefid Ali
Published: July 2021

This research work focuses on the presentation of a novel model for considering the effects of geometrical nonlinearity in the response of bidirectional tuned mass dampers (TMDs). A new form of nonlinear equations of motion is derived. Unlike the conventional linear model, herein, the equations of motion are coupled in two orthogonal directions. The response of the novel nonlinear equations is obtained and compared to the typical linear equations and it is shown that the linear ones are not accurate enough to model the response of the multidirectional TMDs. Perturbation analysis is done to assess the response of TMD system under two internal resonance cases. In the proposed model, phenomena such as jump and energy transfer can take place. The effects of excitation amplitude, damping ratios, and frequency detuning parameters are investigated on the jump and energy transfer phenomena. According to the proposed nonlinear equations, the performance of the bidirectional TMDs depends on the excitation amplitude. Moreover, in some cases, by considering the nonlinear terms in the bidirectional motion equations of TMDs, their performance is improved. However, the nonlinear terms may affect the performance of TMDs negatively, which leads to a very high amplitude of the responses in the main controlled structure under seismic and harmonic excitations.
Formation, mechanism and significance of alluvial‐dammed lakes in Golmud River catchment, north‐eastern Qinghai‐Tibetan Plateau
Authors: An Fuyuan , Chen Tianyuan , Li Xiangzhong , Liu Xiangjun , Wang Yixuan , Chen Zongyan , Chongyi E
Published: July 2021

This study investigated a series of dammed lakes and downstream‐adjacent alluvial fans in the upstream to middle reaches of the Golmud River in the eastern Kunlun Mountain, on the north‐eastern Qinghai‐Tibetan Plateau (QTP). An optically stimulated luminescence (OSL) chronology shows the sediments of five dammed lakes developed from c. 45–40, 30–25, 18–14, and 12–8 ka, corresponding to MIS 3b, late MIS 3a, Last Deglaciation, and early Holocene, respectively. The remote sensing data show these dammed lakes have a total area of 109.4 km2, with the lake volume of more than 4.0 km3. Symmetric alluvial fans from north–south tributary valleys produced OSL ages of c. 61–52, 42–31, 26–20, and 16–10 ka, corresponding to glaciation periods: the MIS 3c and MIS 3a, MIS 2, and the Last Deglaciation. This suggests that glacial activity is responsible for the alluvial fan development, where dammed rivers occurred first, but lake formation did not take place synchronously until later periods of strong hydrologic activity, resulting from northward intrusions of the Indian summer monsoon (ISM) or glacier melt. Thus, the blocking pattern is that river valleys were dammed during periods of glacial activity and lakes formed during wet periods. The lake formation and subsequent drainage may have resulted in: (i) impeded headwater incision and strengthening of downstream dissection; (ii) enriched the halite and potash in the distal Qarhan Salt Lake through hydrologic and hydrochemical processes of abundant water input, the salt lake expansion, salt redissolution from playa and final resedimentation during later dry periods. The alluvial‐dammed lake pattern in the mountain‐basin systems of eastern Kunlun Mountain offers a model for assessing the linkages between monsoon dynamics, geomorphic processes and distal salt lake evolutions in other arid regions.
How sediment composition and flow rate influence downstream channel morphodynamics upon dam removal
Authors: Curran Joanna Crowe , Coveleski Kristen Cannatelli
Published: July 2021

The process of dam removal establishes the channel morphology that is later adjusted by high‐flow events. Generalities about process responses have been hypothesized, but broad applicability and details remain a research need. We completed laboratory experiments focused on understanding how processes occurring immediately after a sediment release upon dam removal or failure affect the downstream channel bed. Flume experiments tested three sediment mixtures at high and low flow rates. We measured changes in impounded sediment volume, downstream bed surface, and rates of deposition and erosion as the downstream bed adjusted. Results quantified the process responses and connected changes in downstream channel morphology to sediment composition, temporal variability in impounded sediment erosion, and spatial and temporal rates of bedload transport.

Within gravel and sand sediments, the process response depended on sediment mobility. Dam removals at low flows created partial mobility with sands transporting as ripples over the gravel bed. In total, 37% of the reservoir eroded, and half the eroded sediment remained in the downstream reach. High flows generated full bed mobility, eroding sands and gravels into and through the downstream reach as 38% of the reservoir eroded. Although some sediment deposited, there was net erosion from the reach as a new, narrower channel eroded through the deposit. When silt was part of the sediment, the process response depended on how the flow rate influenced reservoir erosion rates. At low flows, reservoir erosion rates were initially low and the sediment partially exposed. The reduced sediment supply led to downstream bed erosion. Once reservoir erosion rates increased, sediment deposited downstream and a new channel eroded into the deposits. At high flows, eroded sediment temporarily deposited evenly over the downstream channel before eroding both the deposits and channel bed. At low flows, reservoir erosion was 17–18%, while at the high flow it was 31–41%.
UAV RGB, thermal infrared and multispectral imagery used to investigate the control of terrain on the spatial distribution of dryland biocrust
Authors: Blanco‐Sacristán Javier , Panigada Cinzia , Gentili Rodolfo , Tagliabue Giulia , Garzonio Roberto , Martín M. Pilar , Ladrón de Guevara Mónica , Colombo Roberto , Dowling Thomas P. F. , Rossini Micol
Published: July 2021

Biocrusts (topsoil communities formed by mosses, lichens, bacteria, fungi, algae, and cyanobacteria) are a key biotic component of dryland ecosystems. Whilst climate patterns control the distribution of biocrusts in drylands worldwide, terrain and soil attributes can influence biocrust distribution at landscape scale. Multi‐source unmanned aerial vehicle (UAV) imagery was used to map and study biocrust ecology in a typical dryland ecosystem in central Spain. Red, green and blue (RGB) imagery was processed using structure‐from‐motion techniques to map terrain attributes related to microclimate and terrain stability. Multispectral imagery was used to produce accurate maps (accuracy > 80%) of dryland ecosystem components (vegetation, bare soil and biocrust composition). Finally, thermal infrared (TIR) and multispectral imagery was used to calculate the apparent thermal inertia (ATI) of soil and to evaluate how ATI was related to soil moisture (r2 = 0.83). The relationship between soil properties and UAV‐derived variables was first evaluated at the field plot level. Then, the maps obtained were used to explore the relationship between biocrusts and terrain attributes at ecosystem level through a redundancy analysis. The most significant variables that explain biocrust distribution are: ATI (34.4% of variance, F = 130.75; p < 0.001), Elevation (25.8%, F = 97.6; p < 0.001), and potential solar incoming radiation (PSIR) (52.9%, F = 200.1; p < 0.001). Differences were found between areas dominated by lichens and mosses. Lichen‐dominated biocrusts were associated with areas with high slopes and low values of ATI, with soil characterized by a higher amount of soluble salts, and lower amount of organic carbon, total phosphorus (Ptot) and total nitrogen (Ntot). Biocrust‐forming mosses dominated lower and moister areas, characterized by gentler slopes and higher values of ATI with soils with higher contents of organic carbon, Ptot and Ntot. This study shows the potential to use UAVs to improve our understanding of drylands and to evaluate the control that the terrain has on biocrust distribution.
Parasites of the past: 90 years of change in parasitism for English sole
Authors: Welicky Rachel L , Preisser Whitney C , Leslie Katie L , Mastick Natalie , Fiorenza Evan , Maslenikov Katherine P , Tornabene Luke , Kinsella John M , Wood Chelsea L
Published: July 2021

Historical data are extremely rare but essential for ascertaining whether contemporary infectious disease burdens are unusual. Natural history collections are a valuable source of such data, especially for reconstructing long timelines of parasite abundance. We quantified the parasites of 109 museum specimens of English sole (Parophrys vetulus), an economically important flatfish, collected from Puget Sound, Washington, over a 90‐year period (1930–2019). We counted nearly 2,500 individual parasites representing 23 distinct species/morphotypes and four broad taxonomic groupings. Of the 12 taxa that were prevalent enough to include in the analysis, nine did not change in abundance over time, two (an acanthocephalan and a trematode) decreased, and one (another trematode) increased. By broad taxonomic grouping, nematodes, trematodes, and leeches exhibited no change over time, whereas acanthocephalans declined significantly. The diverging patterns among parasite taxa suggest a double‐edged sword of responses to long‐term ocean change: some parasites might be on the rise, while others are declining.
Correlation analysis of microstructure, protein pattern, and thermal properties of Procambarus clarkia subjected to different cryogenic treatments
Authors: Shi Liu , Li Xin , Xiong Guangquan , Wu Wenjin , Ding Anzi , Qiao Yu , Liao Li , Chen Dongqing , Wang Lan
Published: July 2021

The objective of this work was to investigate the freezing and storage temperature (−80 and −18℃) on the microstructure, protein pattern, and thermal properties of red swamp crayfish after one‐week storage, and a Pearson correlation analysis was performed among these attributes. After cryogenic treatments for short‐term storage, Tp (pretein denaturation temperature) was significantly raised (p < .05) except for samples frozen at −80℃ prior to store at −18℃ (−80/‐18). Samples frozen and stored at −80℃ (−80/‐80) had lower number and sum area of white regions in histology, higher intensity of most protein bands in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) image, and relatively higher Tp and ΔH (p < .05), while −80/‐18 samples had lower intensity of most protein bands and TP 2, and higher number and sum area of white regions and ΔH 2 (p < .05). Pearson's analysis results showed the intensive TN T and MLC 1 band could be potentially considered as the markers of tissue integrity and protein degradation. Therefore, the three attributes could be applied to comprehensively assess the quality of frozen aquatic products, and −80/‐80 treatment was appropriate for crayfish preservation.
Postharvest melatonin treatment inhibited longan (Dimocarpuslongan Lour.) pericarp browning by increasing ROS scavenging ability and protecting cytomembrane integrity
Authors: Luo Tao , Yin Feilong , Liao Lingyan , Liu Yunfen , Guan Boyang , Wang Min , Lai Tingting , Wu Zhenxian , Shuai Liang
Published: July 2021

Postharvest melatonin treatments have been reported to improve the quality and storability, especially to inhibit browning in many fruits, but the effect had not been systematically investigated on longan fruit. In this study, the effect of 0.4 mM melatonin (MLT) dipping on the quality and pericarp browning of longan fruits stored at low temperature was investigated. The MLT treatment did not influence the TSS content of longan fruits but lead to increased lightness and h° value while decreased a* value of pericarp. More importantly, the treatment significantly delayed the increase in electrolyte leakage and malonaldehyde accumulation, inhibited the activities of polyphenol oxidase and peroxidase, and thus retarded pericarp browning. In addition, the treatment significantly inhibited the production of O2•− and H2O2 while promoted the accumulation of glutathione, flavonoids, and phenolics at earlier storage stages in longan pericarp. Interestingly, the activities of ascorbate peroxidase (APX) and superoxide dismutase (SOD) were significantly upregulated but activities of catalase were downregulated in the MLT‐treated longan pericarp. MLT treatment effectively enhanced APX and SOD activities, increased flavonoid, phenolics, and glutathione content, protected cytomembrane integrity, inhibited the production of O2•− and H2O2 and browning‐related enzymes, and thus delayed the longan pericarp browning.
Predictors of surgical site infection and pneumonia following oral cavity tumor surgery
Authors: Karthik Konagalla , Dhiwakar Muthuswamy
Published: July 2021

Background

To identify risk factors for surgical site infection (SSI) and pneumonia following oral cavity tumor surgery.

Methods

Retrospective chart review of a consecutive series of patients undergoing oral cavity resection. Several clinicopathologic variables were tested for their association with SSI and pneumonia.

Results

Three hundred and forty‐four cases in 330 patients were included. Incidence of SSI and pneumonia was 67 (19.5%) and 38 (11%), respectively. On multivariate analysis, marginal mandibulectomy and segmental mandibulectomy were independent risk factors for SSI, whereas time under anesthesia (TUA) was an independent risk factor for pneumonia. Receiver operating characteristic curve identified 390 min as the cutoff above which pneumonia was predicted with a high degree of accuracy.

Conclusions

In oral cavity resections, mandibulectomy predisposes to SSI. Further, prolonged TUA (>390 min) is a powerful predictor for pneumonia. As it is a modifiable risk factor, reduction in TUA might correspondingly lower the incidence of postoperative pneumonia.
Inhibition of Thiol‐Mediated Uptake with Irreversible Covalent Inhibitors
Authors: Lim Bumhee , Cheng Yangyang , Kato Takehiro , Pham Anh‐Tuan , Le Du Eliott , Mishra Abhaya Kumar , Grinhagena Elija , Moreau Dimitri , Sakai Naomi , Waser Jerome , Matile Stefan
Published: July 2021

Thiol‐mediated uptake is emerging as method of choice to penetrate cells. This study focuses on irreversible covalent inhibitors of thiol‐mediated uptake. High‐content high‐throughput screening of the so far largest collection of hypervalent iodine reagents affords inhibitors that are more than 250 times more active than Ellman’s reagent and rival the best dynamic covalent inhibitors. Comparison with other irreversible reagents reveals that inhibition within one series follows reactivity, whereas inhibition across series deviates from reactivity. These trends support that molecular recognition, besides dynamic covalent exchange, contributes significantly to thiol‐mediated uptake. The most powerful inhibitors besides the best hypervalent iodine reagents were Fukuyama’s nosyl protecting group and super‐cinnamaldehydes that have been introduced as irreversible activators of the pain receptor TRPA1. Considering that several viruses use different forms of thiol‐mediated uptake to enter cells, the identification of new irreversible inhibitors of thiol‐mediated uptake is of general interest for the discovery of new antivirals.
Thermal analysis of buoyancy‐motivated Casson fluid flow with time‐independent chemical reaction under Lorentz forces
Authors: Basha Hussain , Nedunuri Naresh Kumar , Reddy Gudala Janardhana , Ballem Sreenivasulu
Published: July 2021

The present research study examines the magneto‐hydrodynamic natural convection visco‐elastic boundary layer of Casson fluid past a nonlinear stretching sheet with Joule and viscous dissipation effects under the influence of chemical reaction. To differentiate the visco‐elastic nature of Casson fluid with Newtonian fluids, an established Casson model is considered. The present physical problem is modeled by utilizing the considered geometry. The resulting system of coupled nonlinear partial differential equations is reduced to a system of nonlinear ordinary differential equations by applying suitable similarity transformations. Numerical solutions of these reduced nondimensional governing flow field equations are obtained by applying the Runge‐Kutta integration scheme with the shooting method (RK‐4). The physical behavior of different control parameters is described through graphs and tables. The present study describes that the velocity and temperature profiles decreased for increasing values of Casson fluid parameter. Velocity field diminished for the increasing nonlinear parameter whereas velocity profile magnified for increasing free convection parameter. Thermal field enhanced with increasing magnetic parameter in the flow regime. The concentration profile decreased for the rising values of the chemical reaction parameter. The magnitude of the skin‐friction coefficient enhanced with increasing magnetic parameter. Increasing Eckert number increases the heat transfer rate and increasing chemical reaction parameter magnifies the mass transfer rate. Finally, the similarity results presented in this article are excellently matched with previously available solutions in the literature.
A novel, re‐usable ‘Safe birth Tray’ for postpartum blood loss monitoring: A preliminary acceptability assessment
Authors: Singata‐Madliki Mandisa , Hofmeyr G Justus
Published: July 2021

Synopsis

A novel, re‐usable ‘Safe Birth Tray’ for blood loss monitoring and early detection of postpartum hemorrhage was found to be easy to use, acceptable, comfortable, and useful by participants and midwives.
Detection of lung tumor using dual tree complex wavelet transform and co‐active adaptive neuro fuzzy inference system classification approach
Authors: Kailasam Manoj Senthil , Thiagarajan MeeraDevi
Published: July 2021

The automatic detection and location of the tumor regions in lung images is more important to provide timely medical treatments to patients in order to save their lives. In this article, machine learning‐based lung tumor detection, classification and segmentation algorithm is proposed. The tumor classification phase first smooth the source lung computed tomography image using adaptive median filter and then discrete time complex wavelet transform (DT‐CWT) is applied on this smoothed lung image to decompose the entire image into a number of sub‐bands. Along with the decomposed sub‐bands, DWT, pattern, and co‐occurrence features are computed and classified using co‐active adaptive neuro fuzzy inference system (CANFIS). The tumor segmentation phase uses morphological functions on this classified abnormal lung image to locate the tumor regions. The multi‐evaluation parameters are used to evaluate the proposed method. This method is compared with the other state‐of‐the‐art methods on the same lung image from open‐access dataset.