bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of preemergence herbicides on establishment of little bluestem and sideoats grama golf course rough
Authors: Richard Michael P. , Morrison Jesse I. , McCurdy James D.
Published: June 2020

Native warm‐season grass (NWSG) roughs provide environmental and aesthetic value to golf courses; however, weed competition is a constraint during establishment. This research evaluated the effects of common turfgrass preemergence herbicides on establishment of newly seeded 1:1 mixture of little bluestem [Schizachyrium scoparium (Michx.) Nash] and sideoats grama [Bouteloua curtipendula (Michx.) Torr.] (14.3 lb total seed acre−1) rough. Herbicides applied immediately after drill‐seeding included: atrazine (1.0 lb a.i. acre−1), dimethenamid‐P (1.5 lb acre−1), dithiopyr (0.38 lb acre−1), imazapic (0.06 lb acre−1), indaziflam (0.029 lb acre−1), isoxaben (1.0 lb acre−1), S‐metolachlor (2.48 lb acre−1), oxadiazon (4.0 lb acre−1), pendimethalin (1.47 lb acre−1), prodiamine (0.75 lb acre−1), and simazine (1.0 lb acre−1). Effects upon NWSG plant density and biomass, as well as smooth crabgrass [Digitaria ischaemum (Schreb.) Schreb. ex Muhl.] control, were evaluated in 2017 and 2018. Across years, imazapic, dimethenamid, oxadiazon, and metolachlor controlled crabgrass >90%. In 2017, little bluestem plant density assessed 4 months after treatment was 2 to 13 times greater in imazapic‐treated plots than all other treatments except for those treated with isoxaben and simazine. Application of imazapic resulted in greater little bluestem aboveground biomass than all other herbicide treatments, except simazine, in 2017. In 2018, imazapic resulted in greater little bluestem plant density than the untreated control, atrazine, prodiamine, oxadiazon, isoxaben, or simazine. Although it was a minor component of the sward, sideoats grama was generally tolerant of imazapic. Imazapic application during seeded establishment of little bluestem and sideoats grama golf course rough provides acceptable crop tolerance and smooth crabgrass control.
An α2,3‐Sialyltransferase from Photobacterium phosphoreum with Broad Substrate Scope: Controlling Hydrolytic Activity by Directed Evolution
Authors: Mertsch Alexander , He Ning , Yi Dong , Kickstein Michael , Fessner Wolf‐Dieter
Published: June 2020

Defined sialoglycoconjugates are important molecular probes for studying the role of sialylated glycans in biological systems. We show that the α2,3‐sialyltransferase from Photobacterium phosphoreum JT‐ISH‐467 (2,3SiaTpph) tolerates a very broad substrate scope for modifications in the sialic acid part, including bulky amide variation, C5/C9 substitution, and C5 stereoinversion. To reduce the enzyme's hydrolytic activity, which erodes the product yield, an extensive structure‐guided mutagenesis study identified three variants that show up to five times higher catalytic efficiency for sialyltransfer, up to ten times lower efficiency for substrate hydrolysis, and drastically reduced product hydrolysis. Variant 2,3SiaTpph (A151D) displayed the best performance overall in the synthesis of the GM3 trisaccharide (α2,3‐Neu5Ac‐Lac) from lactose in a one‐pot, two‐enzyme cascade. Our study demonstrates that several complementary solutions can be found to suppress the common problem of undesired hydrolysis activity of microbial GT80 sialyltransferases. The new enzymes are powerful catalysts for the synthesis of a wide variety of complex natural and new‐to‐nature sialoconjugates for biological studies.
A High Faraday Efficiency NiMoO4 Nanosheet Array Catalyst by Adjusting the Hydrophilicity for Overall Water Splitting
Authors: Wang Zining , Wang Hui , Ji Shan , Wang Xuyun , Zhou Pengxin , Huo Shuhui , Linkov Vladimir , Wang Rongfang
Published: June 2020

To obtain a highly active, stable, and binder‐free electrode based on transition‐metal compounds for water splitting, nickel foam‐supported 3D NiMoO4 nanosheet arrays modified with 0D Fe‐doped carbon quantum dots (Fe‐CQDs/NiMoO4/NF) are synthesized. The structure characterizations indicated that 0D Fe‐CQDs are evenly dispersed onto the NiMoO4 sheets of the arrays. The contact angle analysis confirmed that the surface hydrophilia of the arrays is improved after the 0D Fe‐CQDs are deposited 3D on the NiMoO4 sheets. Here, both the activity and durability in electrochemical water splitting are significantly enhanced with the Fe‐CQDs/NiMoO4/NF catalysts. At a current density of 10 mA cm−2, the resultant Fe‐CQDs/NiMoO4/NF revealed an overpotential of only 117 mV for the hydrogen evolution reaction (HER), a relatively low overpotential of 336 mV toward the oxygen evolution reaction (OER), and a Faraday efficiency of up to 99 %. This performance can be attributed to the unique 3D nanosheet array structure, the synergistic effect, and the optimal hydrophilia for gas evolution evolved from the electrode surface.
Trichloro(Dinitrogen)Platinate(II)
Authors: Thomas Gilian T. , Donnecke Sofia , Paci Irina , McIndoe J. Scott
Published: June 2020

Zeise's salt, [PtCl3(H2C=CH2)]−,is the oldest known organometallic complex, featuring ethylene strongly bound to a platinum salt. Many derivatives are known, but none involving dinitrogen, and indeed dinitrogen complexes are unknown for both platinum and palladium. Electrospray ionization mass spectrometry of K2[PtCl4] solutions generate strong ions corresponding to [PtCl3(N2)]−, the identity of which was confirmed through ion‐mobility spectrometry and MS/MS experiments that proved it to be distinct from its isobaric counterparts [PtCl3(C2H4)]−and [PtCl3(CO)]−. Computational analysis established a gas‐phase platinum–dinitrogen bond strength of 116 kJ mol−1, substantially weaker than the ethylene and carbon monoxide analogues but stronger than for polar solvents such as water, methanol and dimethylformamide, and strong enough that the calculated N−N bond length of 1.119 Å represents weakening to a degree typical of isolated dinitrogen complexes.
Management of LDL‐cholesterol after an acute coronary syndrome: Key comparisons of the American and European clinical guidelines to the attention of the healthcare providers
Authors: Gencer Baris , Giugliano Robert P.
Published: June 2020

Guidelines for the management of blood cholesterol were updated in the past year in the United States and Europe, reflecting a more intensive approach to lowering low‐density lipoprotein cholesterol (LDL‐C). The American College of Cardiology/American Heart Association task force on practice guideline released the 2018 guideline on the management of blood cholesterol on behalf of several American societies. Approximately 9 months later, the European Society of Cardiology/European Atherosclerosis Society published their 2019 guideline for the management of dyslipidemias. Both guidelines have similarities for the management of patients with acute coronary syndromes. Both emphasize risk assessment of patients as a main approach to guide therapy; those at higher risk of cardiovascular disease have a greater clinical benefit of LDL‐C reduction by at least 50%. Both guidelines reinforce the indication to lower LDL‐C as an important modifiable risk factor and consider the addition of nonstatin agents, such as ezetimibe and proprotein convertase subtilisin kexin 9 (PCSK9) inhibitors, in addition to lifestyle counseling and high‐intensity statin for further reduction of LDL‐C levels. However, the guidelines have differences in the concepts of treatment thresholds (≥70 mg/dL in the United States) vs treatment goals (< 55 mg/dL in Europe), in the definition of very high‐risk category and in the classes for recommendation for the use of PCSK9 inhibitors.
Health disparities in cervical cancer: Prevalence of high‐risk HPV and cytologic diagnoses according to race
Authors: Miller Daniel , Morris C. Paul , Maleki Zahra , White Marissa , Rodriguez Erika F.
Published: June 2020

Background

In the United States, the rate of cervical cancer is disproportionally higher in Hispanic and Black women compared with White women. In the current study, the authors compared human papillomavirus (HPV) testing and cytology results among Black and White women over a 24‐month period. They then assessed the rates in young women in 2011 compared with 2017 according to race.

Methods

The authors searched the gynecologic cytology case files for Black and White women treated at Johns Hopkins Hospital across all ages for a period of 24 months (2017‐2019) and compared HPV results and cytologic interpretations. They then compared results among Black and White cohorts of young women (aged 21‐29 years) in 2011 versus 2017.

Results

A total of 26,302 specimens from January 2017 to January 2019, including 11,676 Black women and 14,626 White women, were reviewed. The most common HPV genotype(s) detected were non–HPV‐16 and/or HPV‐18 (non‐16/18) high‐risk HPV (hrHPV) (84% of positive results). Non‐16/18 hrHPV was more common in Black women (1309 women; 15%) compared with White women (1075 women; 9%). Non‐16/18 hrHPV was more commonly observed in association with atypical squamous cells, cannot rule out high‐grade squamous intraepithelial lesion and/or high‐grade squamous intraepithelial lesion (ASC‐H/HSIL) in HPV‐positive Black women compared with White women (P = .007). Black women were found to have higher rates of HPV‐positive Papanicolaou results and high‐grade lesions, including carcinoma (P < .01). In the 2011 cohort, young Black women were found to have a higher rate of ASC‐H/HSIL (P = .003) compared with White women. However, the difference was not noted in the 2017 cohort. There was a decrease in ASC‐H/HSIL in 2017 compared with 2011, with a lower incidence of ASC‐H/HSIL noted among Black women in 2017.

Conclusions

Black women appear to have a higher incidence of higher grade lesions, but the difference between Black and White cohorts was not found to be significant in young women in more recent years.
Underwater image enhancement using improved generative adversarial network
Authors: Zhang Tingting , Li Yujie , Takahashi Shinya
Published: June 2020

The generative adversarial network is widely used in image generation, and the generation of images with different styles is applied to underwater image enhancement. The existing underwater image generative adversarial network does not realize color correction when processing underwater images Therefore, we propose an improved generative adversarial network for image color restoration. Firstly, the loss function in the network is improved to train the dataset. Then the improved network is used to detect the underwater image. After network testing, the underwater image is more satisfactory than the traditional image. Numerical results show that this method has a good color restoration and sharpening effects.
From Very Strong to Inexistent Be−Be Bonds in the Interactions of Be2with π‐Systems
Authors: Vos Eva , Montero‐Campillo M. Merced , Corral Inés , Yáñez Manuel , Alkorta Ibon , Elguero José
Published: June 2020

Isolated Be2is a typical example of a weakly bound system, but interaction with other systems may give rise to surprising bonding features. The interactions between Be2and a set of selected neutral CnHn(n=2–8) π‐systems have been analyzed through the use of G4 and G4MP2 ab initio methods, along with multireference CASPT2//CASPT2 calculations. Our results systematically show that the CnHn−Be2−CnHnclusters formed are always very stable. However, the nature of this interaction is completely different when the π‐system involved is a closed shell species (n=2, 4, 6, 8), or a radical (n=3, 5, 7). In the first case, the interaction does not occur with the π‐system as a whole, but with specific C centers yielding rather polar but strong C−Be bonds. Nonetheless, although the Be−Be distances in these complexes are similar to the ones in compounds with ultra‐strong Be−Be bonds, a close examination of their electron density distribution reveals that no Be−Be bonds exist. The situation is totally different when the interaction involves two π‐radicals, CnHn−Be2−CnHn(n=3, 5, 7). In these cases, a strong Be−Be bond is formed. Indeed, even though Be is electron deficient, the Be2moiety behaves as an efficient electron donor towards the two π‐radicals, so that the different CnHn−Be2−CnHn(n=3, 5, 7) clusters are the result of the interaction between Be22+and two L−anions. The characteristics of these two scenarios do not change when dealing with bicyclic π‐compounds, such as naphthalene and pentalene, because the interaction with the Be2moiety is localized on one of the unsaturated cycles, the other being almost a spectator.
Development and Biological Applications of Fluorescent Opioid Ligands
Authors: Drakopoulos Antonios , Decker Michael
Published: June 2020

Opioid receptors (ORs) are classified among the oldest and best investigated drug targets due to their fundamental role in the treatment of pain and related disorders. ORs are divided in three conventional subtypes (μ, κ, δ) and the non‐classical nocicepetin receptor. All ORs are family A G protein‐coupled receptors (GPCRs), and are located on the cell surface. Modern biophysical methods use light to investigate physiological processes at organismal, cellular and subcellular level. Many of these methods rely on fluorescent ligands, thus highlighting their importance. This review addresses the advancements in the development of opioid fluorescent ligands and their use in biological, pharmacological and imaging applications.
Across the Board: Yang Li on Visible‐Light Photoredox Catalysis
Authors: Li Yang
Published: June 2020

In this series of articles, the board members of ChemSusChem discuss recent research articles that they consider of exceptional quality and importance for sustainability. This entry features Prof. Y. Li, who discusses visible‐light photoredox catalysis by acridinium photocatalysts, which show both powerful oxidative and reductive abilities. She also highlights the mechanism for generation of a neutral acridine radical and its application in the reduction of aryl halides.
Is population subdivision different from speciation? From phylogeography to species delimitation
Authors: Huang Jen‐Pan
Published: June 2020

Species‐level diversity and the underlying mechanisms that lead to the formation of new species, that is, speciation, have often been confounded with intraspecific diversity and population subdivision. The delineation between intraspecific and interspecific divergence processes has received much less attention than species delimitation. The ramifications of confounding speciation and population subdivision are that the term speciation has been used to describe many different biological divergence processes, rendering the results, or inferences, between studies incomparable. Phylogeographic studies have advanced our understanding of how spatial variation in the pattern of biodiversity can begin, become structured, and persist through time. Studies of species delimitation have further provided statistical and model‐based approaches to determine the phylogeographic entities that merit species status. However, without a proper understanding and delineation between the processes that generate and maintain intraspecific and interspecific diversity in a study system, the delimitation of species may still not be biologically and evolutionarily relevant. I argue that variation in the continuity of the divergence process among biological systems could be a key factor leading to the enduring contention in delineating divergence patterns, or species delimitation, meriting future comparative studies to help us better understand the nature of biological species.
Effect of power ultrasound on the extraction of black caraway (Carum carvi L.) and evaluation of their qualitative properties using response surface methodology
Authors: Shaterabadi Dariush , Aboonajmi Mohammad , Ghorbani Javid Majid , Arabhosseini Akbar
Published: June 2020

In this research, ultrasound‐assisted extraction (UAE) with two types of continuous and pulsed sonication extraction was compared with the Soxhlet method in the evaluation of qualitative traits of caraway seeds as a medicinal plant. Treatment conditions were performed at three levels of treatment (continuous and on–off levels), ultrasound power (100, 200, and 300 W), and sonication duration (10, 15, and 20min) using the response surface methodology (RSM) to compare them. Results indicated that yield of the dry extract weight and amount of ascorbic acid increased by the intensity and sonication duration directly but about DPPH radical scavenging capacity there is no direct relation, actually comparing DPPH radical scavenging capacity yields showed that it increased initially from 100W to 200 W, then from 200 to 300W, the result was reversed. It is due to the occurrence of power peaks during extraction , degradation of more and better plant matrices, and better released of the extract in low powers. Results also showed that pulsed sonication method was more effective than continuous to extraction of sensitive components.
Flavor compounds in Vine Tea (Ampelopsis grossedentata) infusions
Authors: Carneiro Renata C. V. , Wang Hengjian , Duncan Susan E. , O'Keefe Sean F.
Published: June 2020

Vine tea (Ampelopsis grossedentata) is a tea traditionally used in Chinese herbal medicine that is rich in the natural antioxidant dihydromyricetin (ampelopsin). In addition to its multiple health benefits, vine tea extracts and dihydromyricetin have been suggested as potential natural antioxidants for food applications, such as soybean oil and meat products. However, there is still little information available on vine tea chemistry, and in particular the volatile profile and sensory characteristics, which can affect product acceptability and restrict its use as a natural antioxidant. The objective of this exploratory study was to identify potential volatile components present in vine tea in order to support further research and applications in the food industry. Vine tea infusions brewed from commercial samples were characterized by acidic pH values and a dark, reddish‐yellow color. Twenty‐one volatile compounds were identified as potential flavor components of vine tea, including aldehydes and ketones. Further studies are suggested to quantify the volatile compounds and understand their importance to vine tea's aroma profile. Sensory studies are also suggested to access consumer's acceptability of vine tea and products containing vine tea as an ingredient.
The Hang Up
Authors: Sullivan Laura Specker
Published: June 2020

Over the past year, our ethics service has had numerous consultations involving patients who use the emergency department for regular dialysis. Sometimes, they have access to outpatient hemodialysis that they forgo; other times, they've been “fired” from this kind of outpatient facility, and so the ED is their last option. In most of these cases, we're called because the patient is disruptive once admitted to the ICU and behavior plans haven't helped. But the call from a resident this March 2020 morning was different, the patient had end‐stage renal disease and often missed hemodialysis, but he wasn't disruptive. “It's just that he comes in after using cocaine, and given scarcity with the coronavirus and ICU beds….” I have come to think that this is one of the more insidious effects of the pandemic: that there will be a resurgence of the view that some patients deserve health care by virtue of their compliant behavior and that those who are nonadherent don't.
Duties toward Patients with Psychiatric Illness
Authors: Conrad Rachel C. , Baum Matthew L. , Shah Sejal B. , Levy‐Carrick Nomi C. , Biswas Jhilam , Schmelzer Naomi A. , Silbersweig David
Published: June 2020

Patients with psychiatric illness feel the brunt of the intersection of many of our society's and our health care system's disparities, and the vulnerability of this population during the Covid‐19 pandemic cannot be overstated. Patients with psychiatric illness often suffer from the stigma of mental illness and receive poor medical care. Many patients with severe and persistent mental illness face additional barriers, including poverty, marginal housing, and food insecurity. Patients who require psychiatric hospitalization now face the risk of transmission of Covid‐19 due to the inherent difficulties of social distancing within a psychiatric hospital. Patients whose freedom and self‐determination have been temporarily overruled as they receive involuntary psychiatric treatment deserve a setting that maintains their health and safety. While tele‐mental health has been rapidly expanded to provide new ways to access psychiatric treatment, some patients may have limitations in technological literacy or access to devices. The social isolation, economic fallout, and potential traumatization related to the current pandemic will disproportionately affect this vulnerable population, and society's duties to them must be considered.
Vulnerable Children in a Dual Epidemic
Authors: Levine Carol
Published: June 2020

Two epidemics—Covid‐19 and opioid use disorder (OUD) —are creating short‐ and long‐term mental and physical health risks for vulnerable children and adolescents. Information about the risks to children from exposure to the coronavirus is still fragmentary, but even many healthy children are not getting appropriate health care, such as vaccinations or monitoring of developmental milestones during the Covid‐19 pandemic. Children living in poverty are at heightened risk. Youngsters who are already dealing with OUD in their families—2.2 million as of 2017—face serious consequences stemming from trauma and stress. Although not officially designated by the Centers for Disease Control and Prevention as “adverse childhood experiences” (“ACEs”), these situations meet the CDC's criteria for inclusion, such as death or separation from a parent. It is important to recognize and meet the needs of all these children now and not just when the long‐term consequences become apparent.
Covid‐19: Exposing the Lack of Evidence‐Based Practice in Medicine
Authors: Reisman Jonathan , Wexler Anna
Published: June 2020

The Covid‐19 pandemic has altered the shape of medicine, making in‐person interactions risky for both patients and health care workers. Now, before scheduling in‐person appointments or procedures, physicians are forced to reconsider if they are truly necessary. The pandemic has thus thrown into relief the difference between evidence‐based medical care and traditional aspects of care that lack a strong evidentiary component. In this essay, we demonstrate how this has played out in prenatal care, as well as in other aspects of medical care, during the pandemic. The extent to which these changes will persist beyond the most emergent phases of the pandemic is not clear, though insurance reimbursement practices and patient expectations will be determining factors. One thing, however, is certain: the longer the pandemic continues, the more difficult it will be for providers and patients to return to pre‐Covid norms.
Excavating the Personal Genome: The Good Biocitizen in the Age of Precision Health
Authors: Lee Sandra Soo‐Jin
Published: June 2020

The rise of genomic technologies has catalyzed shifts in the health care landscape through the commercialization of genome sequencing and testing services in the genomics marketplace. The development of consumer genomics into a growing array of information technologies aimed at collecting, curating, and broadly sharing personal data and biological materials reconstitutes the meaning of health and reframes patients into biocitizens. In this context, the good biocitizen is expected to assume personal responsibility for health through consumption of genomic information and acquiescence to public and private efforts at data surveillance and aggregation. These shifts raise fundamental questions about how competing interests of the public, the state, and corporate entities will be reconciled and what trade‐offs are demanded for the promise of precision health.
This is US: Geography of evidence in top health economics journals
Authors: Hirvonen Kalle
Published: June 2020

The Journal of Health Economics and Health Economics are arguably the top two journals in the field of health economics. Together, they published 1,679 empirical research articles in the past decade (2010–2019). In line with analyses based on earlier periods, the empirical evidence in top health economics journals continues to be dominated by the United States (37% of all empirical articles), whereas studies based on low‐income countries remain rare (2%). Countries with higher disease burdens receive generally less attention from health economists publishing at the top of their field. Reflecting this, more research was published based on data from the Nordic countries (27 million people) than from sub‐Saharan Africa and South Asia regions combined (2.9 billion people). Finally, one‐third of the empirical articles did not indicate the country of evidence in the title or the abstract, possibly to signal external validity of the findings. This practice was particularly common for articles based on data from North America with more than half of the articles omitting the country of evidence from the title and the abstract. The study concludes by exploring some hypotheses that may explain these findings.
A comparative study on the physicochemical characteristics of nanoparticles released in vivo from CoCrMo tapers and cement–stem interfaces of total hip replacements
Authors: Crainic Alina M. , Callisti Mauro , van Veelen Arjen , Michalik Agnes , Milton James A. , Palmer Martin R. , Cook Richard B.
Published: June 2020

The good biocompatibility and corrosion resistance of the bulk CoCrMo alloy has resulted in it being used in the manufacture of implants and load bearing medical devices. These devices, however, can release wear and corrosion products which differ from the composition of the bulk CoCrMo alloy. The physicochemical characteristics of the particles and the associated in vivo reactivity are dictated by the wear mechanisms and electrochemical conditions at the sites of material loss. Debris released from CoCrMo hip bearings, taper junctions, or cement–stem interfaces can, therefore, have different chemical and morphological characteristics, which provide them with different in vivo toxicities. Here, we propose to assess and compare the characteristics of the particles released in vivo from CoCrMo tapers and cement–stem interfaces which have received less attention compared to debris originating from the hip bearings. The study uses state‐of‐art characterization techniques to provide a detailed understanding of the size, morphology, composition, and chemistry of the particles liberated from the wear and corrosion flakes from revised hip replacements, with an enzymatic treatment. The phase analyses identified Cr2O3 nanoparticles released from tapers and cement–stem interfaces, whose composition did not vary with origin or particle morphology. The size distributions showed significantly smaller particles were released from the stems, compared to the particles originating from the corresponding tapers. The investigation demonstrates that the tribocorrosive processes occurring at the taper and stem interfaces both result in Cr2O3 nanoparticle formation.
Phase diagrams of the Ziff–Gulari–Barshad model on random networks
Authors: Vilela Edda B. , Fernandes Henrique A. , Paranhos Costa Fábio L. , Gomes Paulo F.
Published: June 2020

In this study, we revisited the Ziff–Gulari–Barshad (ZGB) model in order to study the behavior of its phase diagram when two well‐known random networks play the role of the catalytic surfaces: the random geometric graph and the Erdös–Rényi network. The connectivity and, therefore, the average number of neighbors of the nodes of these networks can vary according to their control parameters, the neighborhood radius α, and the linking probability p, respectively. In addition, the catalytic reactions of the ZGB model are governed by the parameter y, the adsorption rate of carbon monoxide molecules on the catalytic surface. So, to study the phase diagrams of the model on both random networks, we carried out extensive steady‐state Monte Carlo simulations in the space parameters (y, α) and (y, p) and showed that the continuous phase transition is greatly affected by the topological features of the networks while the discontinuous one remains present in the diagram throughout the interval of study.
Numerical simulation of a generalized anomalous electro‐diffusion process in nerve cells by a localized meshless approach in Pseudospectral mode
Authors: Roohani Ghehsareh Hadi , Seidzadeh Maryam Sadat , Etesami Seyed Kamal
Published: June 2020

Pseudospectral techniques are known as powerful tools and highly accurate solvers to deal with partial differential equations. In the current work, a local meshless technique in Pseudospectral mode is employed to deal with an interesting and general mathematical model which describes anomalous electrodiffusion of ions in spiny dendrites, the two‐dimensional variable‐order time fractional nonlinear cable equation. For this purpose, at first step a second‐order implicit difference method and a modified second‐order weighted and shifted Grünwald difference scheme are used to discretize the appearing integer and variable order fractional time derivatives, respectively. Then a local Pseudospectral meshless method based on the sufficiently smooth compactly supported radial point interpolation basis functions is formulated for solving the semidiscretized problem. The main advantage of the proposed computational technique is that it leads to a sparse and better‐conditioned system of algebraic equations. Finally, some numerical experiments are presented to demonstrate and verify the performance and accuracy of the method.
Bioactive compounds and quality evaluation of ‘Wonderful’ pomegranate fruit and juice as affected by deficit irrigation
Authors: Tarantino Annalisa , Difonzo Graziana , Lopriore Giuseppe , Disciglio Grazia , Paradiso Vito Michele , Gambacorta Giuseppe , Caponio Francesco
Published: June 2020

BACKGROUND

Persistent water shortage, typical of Mediterranean agricultural systems, has driven production methods towards the use of regulated deficit irrigation (DI) strategies, which may allow important water savings. To evaluate the extent to which pomegranate (cv. ‘Wonderful’) attributes may differ depending on the irrigation application rates, we investigated the effect of four different irrigation regimes (100, 75, 50, and 25% of maximum crop evapotranspiration – ETC) on their morpho‐pomological, physico‐chemical properties, and bioactive compounds.

RESULTS

The weight and the size of whole fruits, and the number of arils and their weight per fruit, decreased significantly with the restriction of ETC water volumes applied to the crop. Minor differences were observed in soluble solids, pH, color of fruit skins, arils, and juices, although total acidity, maturity index, vitamin C, glucose, and fructose were not affected. However, total phenol content and antioxidant activity in juices were higher in the samples subjected to the DI treatments than in those submitted to full irrigation, showing the highest value at 50% ETC. A similar trend was found for anthocyanins delphinidin‐3,5‐diglucoside and delphinidin‐3‐glucoside, reaching the highest concentration at 50% ETC. Among non‐anthocyanin compounds, punicalagins and pedunculagin were more concentrated in the 75% ETc samples.

CONCLUSION

The results of the present study indicate that the DI strategy throughout all the growing season is likely to have important implication for the pomegranate's physical, chemical, and phytochemical properties. Knowledge of them is useful in view of their processing and nutritional properties. © 2020 Society of Chemical Industry
Factors associated with the use of vertical rectus abdominus myocutaneous flap reconstruction following abdominoperineal resection for anorectal cancer
Authors: Nichols David S. , Satteson Ellen , Harbor Patrick , DeFranzo Anthony , David Lisa , Thompson James T.
Published: June 2020

Background and Objectives

Following abdominoperineal resection (APR), primary closure of the perineal defect is often possible. Some patients, however, require flap reconstruction. Identifying these patients preoperatively is critical to facilitate comprehensive patient counseling and optimize surgical efficacy.

Methods

A retrospective review of patients undergoing APR over a 10‐year period was performed to identify predictive factors for patients requiring reconstruction with a vertical rectus abdominis myocutaneous (VRAM) flap as opposed to primary closure. Student's t and Fisher's exact tests were utilized for statistical analysis.

Results

A total of 158 patients underwent APR, 29 of whom (18%) required a VRAM flap. A higher average skin resection area was seen among those requiring flap reconstruction (P < .0001). Flap reconstruction was also associated with current smoking status (P = .0197), anal tumor location (P < .0001), and neoadjuvant radiation (P = .0457). Although not statistically significant, average tumor diameter was larger in the VRAM flap group compared with the primary closure group.

Conclusions

While the appropriate method of closure for those undergoing APR should be considered on an individual case basis, patients who smoke, have a tumor located at the anus, or require large skin resection are more likely to need flap reconstruction.
The Potential Unique Impacts of Hope and Resilience on Mental Health and Well‐Being in the Wake of Hurricane Harvey
Authors: Long Laura J. , Bistricky Steven L. , Phillips Colleen A. , D'Souza Johann M. , Richardson Angela L. , Lai Betty S. , Short Mary , Gallagher Matthew W.
Published: June 2020

Natural disasters can lead to mental health problems, such as posttraumatic stress disorder (PTSD). Higher levels of loss and/or disruption and prior trauma exposure constitute risk factors for mental illness, whereas protective factors, including hope and resilience, support positive functioning. The present cross‐sectional study used structural equation modeling to examine the relative influence of resilience and hope on mental health and well‐being 1–3 months after Hurricane Harvey made landfall in August 2017, among a sample of 829 adults in the Greater Houston, Texas area. Resilience was more strongly associated with reduced PTSD symptoms, β = −.31, 95% CI [−.42, −.21], than was hope, β = −.17, 95% CI [−;.30, −.04], whereas hope was more strongly associated with components of well‐being, βs = .47–.63. Hope was positively associated with posttraumatic growth, β = .30, 95% CI [.19, .41], whereas resilience was negatively associated with posttraumatic growth, β = −.24, 95% CI [−.35, −.12]. These associations remained consistent after considering risk factors, although more variance in trauma‐related outcomes was risk factors were included in the model. The present results suggest that considering the influence of both risk and resilience factors provides an enhanced picture of postdisaster mental health.
Measuring Trauma Exposure: Count Versus Variety of Potentially Traumatic Events in a Binational Sample
Authors: Rasmussen Andrew , Romero Sara , Leon Michelle , Verkuilen Jay , Morales Priscilla , Martinez‐Maganalles Sophia , García‐Sosa Icelini
Published: June 2020

Traumatic event checklists typically ask respondents to indicate whether they have experienced particular types of potentially traumatic events (PTEs) and then sum these endorsements to gauge cumulative trauma exposure. However, the sum of these endorsements indicates the variety of PTEs respondents have experienced rather than the count of exposure events. The main objective of the present study was to explore the association between PTE count and variety to examine assumptions regarding the use of traumatic event checklists to measure cumulative trauma exposure. The limited empirical research suggests that count and variety are strongly associated; however, there may be variation in magnitude concerning whether participants’ environments confer an increased or decreased risk of exposure. We present Life Event Checklist data from a large sample of Mexican and U.S. participants (n = 1,820), which allowed us to compare reports of count and variety. Count and variety were strongly correlated, Kendall's tau‐b = .74, such that count accounted for 54.6% of the variance in variety. A negative binomial regression analysis revealed that this association was moderated by county and municipio homicide rate, used as a proxy for violent crime, but not by natural disaster history. Variety was more strongly associated with scores on the Posttraumatic Stress Checklist for DSM‐5, Kendall's tau‐b = .26, than was PTE count, Kendall's tau‐b = .22, Fisher's z = −8.04, p < .001. Although there are challenges in estimating PTE counts, the present findings suggest that PTE variety is not a good proxy for cumulative trauma exposure.
Sulphide‐induced stress corrosion cracking and hydrogen absorption of copper in deoxygenated water at 90°C
Authors: Forsström Antti , Becker Richard , Hänninen Hannu , Yagodzinskyy Yuriy , Heikkilä Mikko
Published: June 2020

Stress corrosion cracking (SCC) of oxygen‐free phosphorous‐alloyed copper was investigated in sulphide‐ and chloride‐containing deoxygenated water at 90°C with sulphide concentrations of 0.001 and 0.00001 M. Several intergranular defects were found in the specimen exposed to the high sulphide environment. Similar defects were not found in the low sulphide environment, where only slight corrosion on grain boundaries and slip lines occurred. Hydrogen content measurements show an increase in hydrogen uptake of the plastically deformed specimens, which is dependent on the sulphide concentration and on plastic deformation of copper. However, the highest hydrogen content was measured in friction stir welds, welded in air without shielding gas, and tested in the high sulphide environment. The embedded oxide particles in the weld metal act as local hydrogen trapping sites and selectively react with the sulphide solution. A relatively thick air‐formed oxide film covers the copper canisters when deposited, which transforms into a sulphide film in the repository conditions. Thus, some of the coupon specimens were pre‐oxidised. The conversion of the pre‐existing Cu2O film into Cu2S film occurs quickly and the transformation is almost 100% efficient. The structure and properties of the Cu2S films, susceptibility of copper to sulphide‐induced SCC and hydrogen uptake of copper in reducing, anoxic repository conditions are discussed.
Improving Resistance‐Temperature Characteristic of Polyethylene/Carbon Black Composites by Poly(3,4‐Ethylenedioxythiophene)‐Functionalized Multilayer Graphene
Authors: Shi Guangfa , Cai Xiaomin , Wang Wenqiang , Wang Gengchao
Published: June 2020

Polymeric positive temperature coefficient (PTC) materials can be used to install “brake” technology for the thermal runaway of lithium‐ion batteries. However, it still has poor cycle stability and obvious negative temperature coefficient (NTC) effect, which reduces the reliability of the material. In order to solve these problems, conductive polymer poly(3,4‐ethylenedioxythiophene) (PEDOT) modified multilayer graphene (MLG) conductive additive (PEDOT‐MLG) is introduced into middle density polyethylene/carbon black (MDPE/CB) system. Compared with the conventional modification, the PEDOT modified MLG shows high conductivity and excellent thermal stability. In addition, the introduction of PEDOT‐MLG into MDPE/CB can further reduce the room temperature resistivity due to the good compatibility between the modified graphene and the matrix, thus improving the PTC intensity to 7.1. What is more, MLG limits the re‐aggregation of CB particles when the temperature further rises, which effectively weakens the NTC effect.
Highly Stretchable Tough Elastomers Crosslinked by Spiropyran Mechanophores for Strain‐Induced Colorimetric Sensing
Authors: Cao Ziquan
Published: June 2020

Colorimetric spiropyran as a promising mechanophore has proven to be useful in visualizing stress/strain sensing and damage warning in polymeric materials. However, it remains challenging to prepare spiropyran‐containing mechanochromic materials with excellent mechanical properties. Herein, highly stretchable and tough double‐network elastomers crosslinked by spiropyran mechanophores are reported. The spiropyran‐crosslinked elastomer features both force and UV light‐induced color changes originating from the structural transformation from ring‐close spiropyran form to ring‐open merocyanine form of the mechanophores, and excellent mechanical properties (favorable elasticity of 480 kPa, large stretchability of 3400% strain, and high toughness of 8.4 kJ m−1) benefiting from the energy dissipation by breakage of sacrificial bonds. In particular, it is demonstrated that the multi‐mechanoresponsive and mechanically strong elastomer can be served as a conceptual sensor to quantify mechanical stretchability by a visible color change. This work shows promising potential for mechanochemical sensing applications.
Electromechanically Active As‐Electrospun Polystyrene Fiber Mat: Significantly High Quasistatic/Dynamic Electromechanical Response and Theoretical Modeling
Authors: Ishii Yuya , Yousry Yasmin Mohamed , Nobeshima Taiki , Iumsrivun Chonthicha , Sakai Heisuke , Uemura Sei , Ramakrishna Seeram , Yao Kui
Published: June 2020

Flexible and lightweight pressure sensors have attracted tremendous attention as a promising component of wearable biological motion sensors and artificial electronic skins. Here, the electromechanical response of as‐electrospun fiber mats composed of a commodity polymer, atactic polystyrene, which can be applied in low‐cost/large‐area, flexible, and lightweight pressure sensors is demonstrated. The fiber mat demonstrates a significantly high apparent converse piezoelectric constant of >30 000 pm V−1 under static measurement and ≈13 000 pm V−1 even at a high frequency of 1 kHz. The first theoretical model to explain the unique electromechanical response is constructed, which reveals that the softness and moderate charge of the fiber mat are the reasons for the significantly high electromechanical response. Further, apparent piezoelectric constants obtained by direct measurement are lower than those obtained by the converse measurement, which is attributed to the densification and hardening of the fiber mat due to prepressure applied in direct measurement. These findings are likely to serve as a milestone for the development of large‐area, flexible, and lightweight pressure sensors at low cost, as well as highly movable actuators like optical modulators without a substantial mechanical load.
Stability of the transmission plate equation with a delay term in the moment feedback control
Authors: Ghecham Wassila , Rebiai Salah‐Eddine , Sidiali Fatima Zohra
Published: June 2020

In this paper, we study the stability problem for the transmission plate equation with moment feedback control that contains a delay term and that acts on the exterior boundary. We prove under some assumptions that the closed‐loop system is exponentially stable. To establish this result, we introduce a suitable energy function and use multipliers method and compactness–uniqueness argument.
Real‐time low cost compact liquid‐water binary mixture monitoring sensor
Authors: Khuhro Sadam H. , Sandhu Muhammad Y. , Afridi Sharjeel , Ahmed Arslan
Published: June 2020

This work proposes a novel method for detecting the concentration of water present in liquid‐water binary mixture in real time with a low cost, portable measurement setup. The sensing element in the proposed system is a two‐port microstrip bandstop resonator based on coupled line open‐ended quarter wavelength section. Voltage control oscillator and power detector ICs are used to generate and detect the microwave power at specific bandstop frequency. Water concentrations in commercially available liquids are monitored both in batch and continuous mode of operation using separate 3D printed liquid containing fixtures attached to the open end of the microstrip line. The measured results successfully validate the design theory.
B0 shimming for in vivo magnetic resonance spectroscopy: Experts' consensus recommendations
Authors: Juchem Christoph , Cudalbu Cristina , de Graaf Robin A. , Gruetter Rolf , Henning Anke , Hetherington Hoby P. , Boer Vincent O.
Published: June 2020

Magnetic resonance spectroscopy (MRS) and spectroscopic imaging (MRSI) allow the chemical analysis of physiological processes in vivo and provide powerful tools in the life sciences and for clinical diagnostics. Excellent homogeneity of the static B0 magnetic field over the object of interest is essential for achieving high‐quality spectral results and quantitative metabolic measurements. The experimental minimization of B0 variation is performed in a process called B0 shimming. In this article, we summarize the concepts of B0 field shimming using spherical harmonic shimming techniques, specific strategies for B0 homogenization and crucial factors to consider for implementation and use in both brain and body. In addition, experts' recommendations are provided for minimum requirements for B0 shim hardware and evaluation criteria for the primary outcome of adequate B0 shimming for MRS and MRSI, such as the water spectroscopic linewidth.
Understanding and managing learning in social enterprises: The role of implicit organizational boundaries
Authors: Tandon Ankita , Nair Unnikrishnan K.
Published: June 2020

Successful social enterprises develop innovative context‐specific solutions to social problems in resource‐constrained environments. To achieve this, they harness knowledge resources beyond their organizational boundaries to learn. Yet, there is limited understanding of the role boundaries play in learning. This paper investigates organizational learning in social enterprises from a boundary perspective. It studies the emergence and role of implicit boundaries in learning, critical learning mechanisms, and key agents involved. Following qualitative methodology, data were collected from four Indian social enterprises. Data structures were developed using analytical methods inspired from grounded theory leading to themes and theoretical inferences. Two implicit and dynamic boundaries—competenceandsocial—were identified, which in isolation and through mutual interactions impacted learning. Their movement vis‐à‐vis the structural boundary of the enterprises was traced. Initially mutually exclusive, the two boundaries extended inwards into the enterprises from the external environment, and then moved downwards or upwards over time. Their sustained overlaps and interactions facilitated learning, with middle managers often playing a critical integration role. Specific boundary configurations, learning modes, and critical agents enabling learning are described. This study directs research on learning in social enterprises to specific boundary interactions. It highlights the significance of implicit boundaries, their multiplicity, and dynamism. It directs social enterprises to explicitly recognize the notion of boundaries, and develop competences and processes to manage them for effective learning.
Stereotypes of volunteers and nonprofit organizations' professionalization: A two‐study article
Authors: Peiffer Mathieu , Villotti Patrizia , Vantilborgh Tim , Desmette Donatienne
Published: June 2020

Competence and warmth are two fundamental stereotypical dimensions that frame people's social judgments. Since we currently lack evidence about how the volunteering workforce is socially perceived, this study aims to (a) understand which stereotypes are associated with volunteers, and (b) determine whether these perceptions vary as a result of contextual changes (i.e., professionalization) that have recently characterized nonprofit organizations (NPOs). Two empirical survey‐based studies were conducted in Belgium, one comprising data collected from a general population sample (N = 233), and the other from volunteers (N = 128). Study 1 displayed volunteers being perceived by the general population as warmer rather than competent. Study 2 found that ingroup warmth perceptions in a volunteers' sample decreased as NPOs became progressively more business‐like. Overall, these two studies illustrate that warmth is at the heart of the volunteers' role and show that the increasing professionalization of NPOs affects this perception.