bluuebunny/crossref_metadata_2025 huggingface dataset:
Age-Related Changes in Bone Density, Microarchitecture, and Strength in Postmenopausal Black and White Women: The SWAN Longitudinal HR-pQCT Study
Authors: Johannesdottir Fjola , Putman Melissa S , Burnett-Bowie Sherri-Ann M , Finkelstein Joel S , Yu Elaine W , Bouxsein Mary L
Published: October 2021

Higher fracture risk in White versus Black women is partly explained by lower BMD and worse bone microarchitecture in White women. However, whether rates of decline in bone density, microarchitecture and strength differ between postmenopausal Black and White women is unknown. Further, factors that influence rates of age-related bone microarchitecture deterioration remain ill-defined. Thus, over 6.7 years, longitudinal changes were measured in peripheral volumetric bone mineral density (vBMD), microarchitecture, and strength at the distal radius and tibia using HR-pQCT in postmenopausal Black (n = 80) and White (n = 137) women participating in the Study of Women's Health Across the Nation. It was assessed whether age-related changes in vBMD and microarchitecture were influenced by body weight, body composition, and/or weight change. It was found that at the radius, where White women appeared to have slightly greater rates of loss in total vBMD, cortical bone volume, and porosity than Black women, those differences were attenuated after adjusting for clinical covariates. At the tibia, Black and White women had similar rates of bone loss. Independent of race and other clinical covariates, women with the lowest baseline body weight experienced the greatest decline in total and trabecular vBMD at the radius. Furthermore, women who lost weight over the follow-up period had higher rates of bone loss, particularly at the tibia, compared with those who maintained or gained weight. Higher baseline total body fat mass was also protective of bone loss at both the radius and tibia. In conclusion, these findings indicate that lower fracture risk among postmenopausal Black women is not caused by slower rates of bone deterioration, and highlight the importance for postmenopausal women to avoid lower body weight and excessive weight loss to avert rapid bone loss and subsequent fractures. © 2021 American Society for Bone and Mineral Research (ASBMR).
Examining the relationships between data‐guided innovations and pre‐k students' social‐emotional development
Authors: Salim Khalil B. , Kilmer Ryan P. , Cook James R. , Armstrong Laura M. , Gadaire Andrew P. , Simmons Caitlin J. , Morris Victoria G. , Thiery Tracy L. , Babb Mary J. , Day Peggy W. , Messinger Lindsay G. , Larson Jacqueline C.
Published: October 2021

The present study examined the effects of data‐guided innovations on students’ social‐emotional (SE) development within prekindergarten settings. Specifically, this study examined the effects of a pilot effort that sought to improve instructional quality through the use of structured classroom observations by coaches to help support teacher implementation of curricula and evidence‐based practices. In addition, teachers used formative assessments of students’ SE functioning to guide and individualize their instruction. To examine the effects of the multicomponent intervention, this study compared the SE functioning of students across three conditions: (1) students whose teachers received no data‐guided innovations; (2) students whose teachers received SE formative assessments; and (3) students whose teachers received both SE formative assessments and performance‐based feedback using structured classroom observations. Students whose teachers received both SE formative assessments and performance‐based feedback using structured classroom observations evidenced significantly greater SE competencies than those in the control group. Additionally, students whose teachers just received SE formative assessments evidenced greater SE competencies than those in the control group, however, the differences were not significant. Results indicate the potential value of these data‐guided innovations for improving prekindergarten student outcomes such as SE development and point to the next steps for future research.
Social capital as mediating factor on COVID‐19 induced psychological distress: The case of college students living through an outbreak
Authors: M. Fulkerson Gregory , Thomas Alexander R. , McCarthy Michael , Seale Elizabeth , Han Sallie , Kemmerer Kirsten , Zians James
Published: October 2021

This investigation examines the interplay between individual‐level social capital, psychological distress, and the effects of a coronavirus disease 2019 (COVID‐19) outbreak on a college campus. Data were collected from students at two colleges in early 2021. Hypotheses were formed based on prior research on social capital and the COVID pandemic. A structural equation model was constructed to allow the modeling of both latent and observed variables. The Kessler‐6 measures were used to create a latent psychological distress variable, which was the dependent variable. Predictor variables include whether the student experienced the outbreak, the student's race and gender, and the level of reported individual social capital (having supportive and rewarding relationships). Our findings suggest that the most robust predictor of reduced psychological distress was individual social capital, which also served as an intermediary between the outbreak and distress. Social capital mediates psychological distress in an outbreak.
Biocatalytic depolymerization of waste polyester mooring lines from oil and gas offshore platforms made of poly(ethylene terephthalate) (PET)
Authors: de Castro Aline M , Carniel Adriano , Menezes Sonia M , Chinelatto Júnior Luiz S , de Honorato Hercílio , Lima Aline P , Chaves Erica G
Published: October 2021

BACKGROUND

The global concern of plastic pollution in the environment has consistently been emerging in the past years. As one of the main polymers constituting single‐use products, poly(ethylene terephthalate) (PET) is found in a plethora of packages for diverse sectors, and its recycling has been broadly addressed. However, other relevant industrial PET wastes have not been under investigation for recycling purposes, such as the polyester mooring lines (PMLs) used to anchor offshore oil and gas floating platforms. In this study, the fibers from either new or used PMLs were characterized according to different techniques (differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared spectroscopy, nuclear magnetic resonance and scanning electron microscopy–energy‐dispersive X‐ray spectroscopy), which allowed the interpretation of their chemical and thermal properties. The fibers were then used in depolymerization reactions under the catalysis of the cutinase enzyme from Humicola insolens and under different process conditions (fiber length, buffer composition, enzyme dosage, temperature, pH).

RESULTS

Characterization of PMLs revealed inorganic incrustation in the external fibers, and very similar crystallinity degrees. The molecular weight, on the other hand, was found to be lower in new mooring lines (27 489 g mol−1) as compared to used mooring lines (35 813–36 785 g mol−1). Throughout depolymerization reactions, a total concentration increase of terephthalic acid of up to 7.4 times (2593 μmol L–1) was achieved.

CONCLUSION

The results proved the concept that the studied cutinase can act on PET chains. To the best of our knowledge, this is the first report to describe an enzyme‐catalyzed depolymerization of PET from mooring lines, and the results add relevant knowledge for a circular economy of plastic products.
Interplay between cardiolipin and plasmalogens in Barth syndrome
Authors: Bozelli José Carlos , Epand Richard M.
Published: October 2021

Barth syndrome (BTHS) is a rare inherited metabolic disease resulting from mutations in the gene of the enzyme tafazzin, which catalyzes the acyl chain remodeling of the mitochondrial‐specific lipid cardiolipin (CL). Tissue samples of individuals with BTHS present abnormalities in the level and the molecular species of CL. In addition, in tissues of a tafazzin knockdown mouse as well as in cells derived from BTHS patients it has been shown that plasmalogens, a subclass of glycerophospholipids, also have abnormal levels. Likewise, administration of a plasmalogen precursor to cells derived from BTHS patients led to an increase in plasmalogen and to some extent CL levels. These results indicate an interplay between CL and plasmalogens in BTHS. This interdependence is supported by the concomitant loss in these lipids in different pathological conditions. However, currently the molecular mechanism linking CL and plasmalogens is not fully understood. Here, a review of the evidence showing the linkage between the levels of CL and plasmalogens is presented. In addition, putative mechanisms that might play a role in this interplay are proposed. Finally, the opportunity of therapeutic approaches based on the regulation of plasmalogens as new therapies for the treatment of BTHS is discussed.
Utility, promise, and limitations of liquid chromatography‐mass spectrometry‐based therapeutic drug monitoring in precision medicine
Authors: Gaspar Vanessa P. , Ibrahim Sahar , Zahedi René P. , Borchers Christoph H.
Published: October 2021

Therapeutic drug monitoring (TDM) is typically referred to as the measurement of the concentration of drugs in patient blood. Although in the past, TDM was restricted to drugs with a narrow therapeutic range in order to avoid drug toxicity, TDM has recently become a major tool for precision medicine being applied to many more drugs. Through compensating for interindividual differences in a drug's pharmacokinetics, improved dosing of individual patients based on TDM ensures maximum drug effectiveness while minimizing side effects. This is especially relevant for individuals that present a particularly high intervariability in pharmacokinetics, such as newborns, or for critically/severely ill patients. In this article, we will review the applications for and limitations of TDM, discuss for which patients TDM is most beneficial and why, examine which techniques are being used for TDM, and demonstrate how mass spectrometry is increasingly becoming a reliable and convenient alternative for the TDM of different classes of drugs. We will also highlight the advances, challenges, and limitations of the existing repertoire of TDM methods and discuss future opportunities for TDM‐based precision medicine.
Design of experiment‐based LC‐MS/MS method development for simultaneous estimation of nateglinide and metformin hydrochloride in rat plasma
Authors: Patel Dhrumi , Vora Amisha , Wairkar Sarika , YC Mayur
Published: October 2021

This research aims to develop and validate a bioanalytical method for simultaneous estimation of an antidiabetic combination using LC‐MS/MS in rat plasma. Nateglinide and metformin hydrochloride are commonly used combination for clinical management of Type 2 diabetes. Hence, simultaneous determination in plasma is essential for the rapid analysis of samples from the pharmacokinetic studies. Statistical optimization was carried out for liquid chromatography (LC) parameters and mass spectroscopic (MS) parameters by design of experiment (DoE) (Design Expert Version 11, Stat Ease Inc., USA) approach. A 33full factorial design was used for optimization of LC parameters; %methanol, %formic acid, and flow rate were selected as independent variables, whereas peak area and tailing factor were considered as dependent variables for both drugs. Box–Behnken design was used to optimize MS parameters including drying gas flow rate, nebulizing gas flow rate, DL temperature, heat block temperature, and positive voltage as independent factors, and responses selected were [M + H]+intensity of nateglinide and metformin hydrochloride. The [M + H]+intensity of the optimized method for nateglinide and metformin hydrochloride were 2,462,838 and 11,873,826, respectively. The model was found significant for optimizing LC and MS parameters withp < 0.05 for both nateglinide and metformin hydrochloride. The optimized method was validated as per the ICH‐M10 guideline, which was accurate, precise, and selective. The method was cost‐effective and capable of quantitating concentrations in picogram levels for nateglinide and metformin hydrochloride simultaneously.
Inhibition of receptor‐binding domain—ACE2 interaction after two doses of Sinovac's CoronaVac or AstraZeneca/Oxford's AZD1222 SARS‐CoV‐2 vaccines
Authors: Silva Valéria O. , Yamashiro Rosemeire , Ahagon Cintia M. , de Campos Ivana B. , de Oliveira Isabela P. , de Oliveira Elaine L. , López‐Lopes Giselle I. S. , Matsuda Elaine M. , Castejon Marcia J. , de Macedo Brígido Luís F.
Published: October 2021

Practical laboratory proxies that correlate to vaccine efficacy may facilitate trials, identify nonresponders, and inform about boosting strategies. Among clinical and laboratory markers, assays that evaluate antibodies that inhibit receptor‐binding domain (RBD) ligation to angiotensin‐converting enzyme‐2 receptor (receptor‐binding inhibition [RBI]) may provide a surrogate for viral neutralization assays. We evaluated RBI before and after a median of 34 days (interquartile range [IQR]: 33–40) of the second dose of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) Sinovac's CoronaVac (CN) or AstraZeneca/Oxford's AZD1222 (AZ) vaccines in 166 individuals. Both vaccines elicited high inhibitory titers in most subjects, 95% (158/166), with signal inhibition above 30% and 89% (127/143) with more than fourfold increase from prevaccination titers, but titers tend to decrease over time. Both postvaccination inhibitory titers (95%, IQR 85%–97% for AZ vs. 79%, IQR 60%–96% for CN, p = 0.004) and pre/post‐titer increase (AZ 76%, IQR 51%–86% for AZ vs. 47%, IQR 24%–67% for CN, p < 0.0001) were higher among AZ vaccinees. Previous serological reactivity due to natural infection was associated with high prevaccination signal inhibition titers. The study documents a robust antibody response capable of interfering with RBD–angiotensin‐converting enzyme binding. Evaluation of SARS‐CoV‐2 infection incidence in these populations is necessary to assess its association to protection and its duration.
Effects of nitrogen addition on plant manganese nutrition in a temperate steppe
Authors: Yang Yan‐Ru , Hou Shuang‐Li , Zhang Zhi‐Wei , Hu Yan‐Yu , Ding Cong , Yang Guo‐Jiao , Lü Xiao‐Tao
Published: October 2021

Background

Manganese (Mn) is an essential nutrient for plant growth and a key factor driving litter decomposition. Nitrogen (N) deposition is expected to enhance soil Mn availability via soil acidification, and subsequently to increase plant Mn concentrations.

Aims

We aimed to quantify the responses of Mn concentrations in green and senesced shoots at both species and community levels to N addition, and determine whether N addition would decrease Mn retranslocation efficiency during plant senescence.

Methods

We examined the changes of Mn concentrations in soil and in green and senesced shoots of all plant species across multiple N addition rates ranging from 0 to 50 g N m−2 y−1 in a temperate steppe after six years treatments. Plant Mn retranslocation efficiency were quantified at species, life form, and community levels. The relationship between plant Mn nutritional parameters and soil Mn availability across the N addition gradient was analyzed.

Results

There were positive correlations between plant Mn concentrations and N addition rates for most species. Relative to the control plots, community‐level mean Mn concentration in green and senesced shoots in the plots received the highest level of N addition increased by 137.50% (from 0.19 mg kg−1 to 0.08 mg kg−1) and 187.50% (from 0.23 mg kg−1 to 0.08 mg kg−1), respectively. There was no correlation between Mn retranslocation efficiency and N addition rates at species, life form and community levels. Plant Mn status was weakly correlated with soil Mn concentrations for most species.

Conclusions

Plant Mn retranslocation showed conserved responses to increasing N addition rates, which would be an adaptive strategy for plants in face of N‐induced higher soil Mn availability.
Holocene hydroclimate changes on the north‐eastern Tibetan Plateau inferred from geochemical records in Lake Gyaring
Authors: Ning Dongliang , Jiang Qingfeng , Ji Ming , Xu Yuchen , Kuai Xiang , Ge Ying , Zhao Wenwei
Published: October 2021

The north‐eastern Tibetan Plateau (TP) is an ideal region for understanding the interaction between the Asian Summer Monsoon (ASM) and the Westerlies. Here we present a high‐resolution elemental record from Lake Gyaring in the source region of the Yellow River to investigate the paleo‐hydroclimate changes over the past ~10 ka. Our results show that lithogenic elements (Ti, Rb, Mn, Ti, Zn and Ni) increased while carbonate‐related elements (Ca, Sr and Mg) decreased up the core sediments, indicating that the effective moisture on the north‐eastern TP has steadily increased throughout the Holocene. This inference is also supported by the gradual augmentation and diminution of Rb/Sr and Ca/(Ti + Fe + Al) ratios, respectively. The persistent wetting trend on the north‐eastern TP inferred from our study disagrees with the Holocene pattern of the ASM but corresponds well with that of the Westerlies. This implies that the strengthening Westerlies since the Holocene might have played a more important role than monsoon circulation in controlling the hydroclimate changes on the north‐eastern TP. However, the significant increase in the mid‐Holocene might be related to the combined effects of the strengthened ASM and Westerlies. Ultimately, Northern Hemisphere solar insolation and the substantial remnant of ice sheets might have controlled Holocene moisture availability on the north‐eastern TP through their influence on the intensity of the Westerlies and ASM as well as Atlantic Ocean sea surface temperatures.
What happens to patients undergoing cancer surgery with psychiatric comorbidities?: A nationwide retrospective cohort study
Authors: Toraih Eman , Hussein Mohammad , Trinh Lily N. , Zerfaoui Mourad , Kandil Emad
Published: October 2021

Objective

We aimed to describe the surgical outcomes and readmissions rates in patients with psychological comorbidities who underwent surgical intervention for cancer.

Background

The Hospital Readmission Reduction Program, a campaign by the Affordable Care Act, penalizes hospitals for greater readmission rates. One prevalent patient risk factor associated with hospital readmission is a comorbid psychiatric condition. Currently, no studies exist identifying psychiatric comorbidities and their effects on patients with cancer undergoing surgical intervention.

Methods

A cross‐sectional analysis was performed using the Nationwide Readmissions Database for 2010–2014 and included adult patients undergoing cancer resection operations. Multivariable logistic regression analyses were utilized to assess determinants of surgical outcomes and readmissions.

Results

Of 1 016 636 eligible patients, 11.6% had psychiatric comorbidities. Patients with psychiatric disorders had greater risks of mortality (odds ratio [OR] = 1.21, 95% confidence interval [CI] = 1.18–1.25), complications (OR = 1.51, 95%CI = 1.50–1.52), extended length of stay (OR = 1.21, 95%CI = 1.20–1.22), and incurred healthcare expenditure at primary admission (OR = 1.16, 95% CI = 1.15–1.18). Psychiatric comorbidities were associated with an increased likelihood of readmission (OR = 1.13, 95%CI = 1.11–1.15).

Conclusions

Concomitant psychiatric conditions were attributed to poor surgical outcomes and a higher risk of readmissions. Multidisciplinary care within the perioperative setting should be encouraged for patients with psychiatric disorders.
Development and validation of a liquid chromatography‐tandem mass spectrometry method with triple‐stage fragmentation to determine levetiracetam in epileptic patient serum and its application in therapeutic drug monitoring
Authors: Ji Zhengchao , Yin Lei , Li Yanyan , Yang Xiaoquan , Lin Lin , Liu Lingling , Jiang Yi , Huang Jing
Published: October 2021

Levetiracetam is an antiepileptic drug that is primarily approved by the Food and Drug Administration for the treatment of focal and generalized seizures. This study describes the development and validation of a highly selective and sensitive liquid chromatography‐tandem mass spectrometry method with triple‐stage fragmentation to determine levetiracetam in epileptic patient serum. After simple protein precipitation, the analytes were separated on a short reversed‐phase column (Agilent Poroshell 120 SB‐C18 column, 4.6 × 50 mm, 2.7 μm) using isocratic elution with 25% 0.1% formic acid in water (solvent A) and 75% methanol (solvent B) at a flow rate of 0.8 ml/min. The linear range is 0.5–50 μg/mL (R2 > 0.99). All the validation data, such as lower limit of quantification, linearity, specificity, recoveries, matrix effects, and other parameters, fit the request of biological method validation guidance. Passing–Bablok regression coefficients demonstrated that there is no constant bias and no proportional bias between the liquid chromatography‐tandem mass spectrometry methods with triple‐stage fragmentation and liquid multiple reaction monitoring. Bland–Altman plot showed that the developed liquid chromatography‐tandem mass spectrometry method with triple‐stage fragmentation method is reliable and accurate to determine levetiracetam in human serum.
Age differences in allostatic load among veterans: The importance of combat exposure
Authors: Piazza Jennifer R. , Landes Scott D. , Stawski Robert S.
Published: October 2021

The current study examinedage differences in allostatic load among nonveterans, noncombat veterans, and combat veterans. Participants included 280 individuals from the Midlife Development in the United States (MIDUS) survey, including 164 veterans (n = 48 combat veterans; n = 116 noncombat veterans) and 116 nonveterans. Age differences in allostatic load were similar among nonveterans and noncombat veterans, B = 0.002, SE = .011, p = .878, with older adults showing higher levels of allostatic load than their comparatively younger counterparts. Among combat veterans, however, a different pattern emerged. In this group, levels of allostatic load were similar across age, seemingly due to higher levels of allostatic load among younger combat veterans, B = −0.029, SE = .014, p = .031, ƞp2 = .022. Results reveal the importance of considering combat exposure when examining health outcomes of military veterans, particularly in the context of age.
Racial, ethnic, and neighborhood income disparities in childhood posttraumatic stress and grief: Exploring indirect effects through trauma exposure and bereavement
Authors: Douglas Robyn D. , Alvis Lauren M. , Rooney Evan E. , Busby Danielle R. , Kaplow Julie B.
Published: October 2021

Previous findings suggest that experiences with systems of oppression that disproportionately affect individuals based on race and neighborhood residency (e.g., systemic racism, neighborhood income disadvantage [NID]) can be associated with higher odds of developing psychological problems following traumatic events. Although race/ethnicity and NID residency are often associated, they are separate concepts that play unique roles in mental health outcomes among youth. Residents of Black, Latinx, and income‐disadvantaged communities also have an increased risk of exposure to polyvictimization and the loss of multiple loved ones. Studies have not carefully delineated the potential relations between race/ethnicity and NID residency, polyvictimization, accumulated losses, and trauma and grief outcomes in youth. We examined mediation models to investigate whether polyvictimization, the loss of multiple loved ones, and exposure to violent death were potential mechanisms through which race/ethnicity and NID would predict trauma and grief outcomes in youth. Participants (N = 429) included Black (19.9%), Latinx (36.0%), and White (27.3%) children and adolescents who were assessed through a routine baseline assessment at a trauma and grief outpatient clinic. Black youth reported significantly elevated posttraumatic stress and maladaptive grief symptoms through higher polyvictimization and violent death exposure relative to White youth, βs = .06–.12, ps <.001. Latinx identity and NID were positively and directly associated with specific domains of maladaptive grief reactions, βs = .10–.17, ps < .001. If replicated longitudinally, these findings suggest that polyvictimization and violent death exposure may be mechanisms through which Black youth develop more severe traumatic stress and grief reactions.
Commentary on the special issue on disproportionate exposure to trauma: Trauma, stress, and adversities and health disparities among disenfranchised groups globally during the COVID pandemic
Authors: Seedat Soraya
Published: October 2021

The papers in this Journal of Traumatic Stress special issue on disproportionate adversity cover the gamut of discrimination traumas and stressors, including microaggressions, a more insidious forms of discrimination, and their often‐devastating and wide‐ranging mental health sequelae, in disproportionately affected disenfranchised groups. Discrimination based on race, ethnicity, gender, and sexual orientation commonly confers cumulative and chronic effects. In the field of traumatic stress studies, several types of identity‐linked traumatic events have been identified and empirically investigated as posttraumatic stress disorder (PTSD)–producing experiences. Collectively, the 13 papers included in this special issue raise questions about the definition, conceptualization, and categorization of various forms of explicit and implicit identity‐linked trauma. These papers highlight the need for acceptance of a shared nomenclature and better differentiation of both causal and correlational associations with acute and chronic PTSD, depression, suicide risk, alcohol misuse, and other mental health outcomes. In this commentary, the discussion is extended to COVID‐19, a disease that has been globally devastating for many. On multiple levels (i.e., physical, mental, emotional, economic, and social), COVID‐19 has magnified the prepandemic fault lines of race, ethnicity, gender, gender identity, and sexual orientation. Applying a syndemic framework to the health impact of COVID‐19 and, arguably, the most pervasive identity linked epidemic worldwide—systemic racism—brings perspective to the biological and social forces that are likely to be driving the convergence of COVID‐19, systemic racism, and chronic health inequities, and may be informative in guiding evidence‐based strategies for managing racial trauma in the context of COVID‐19.
Sentinel Lymph Node Biopsy Versus Elective Node Dissection in Stage cT1‐2N0 Oral Cavity Cancer
Authors: Saleem Matthew I. , Peng Travis , Zhu Daniel , Wong Amanda , Pereira Lucio M. , Tham Tristan
Published: October 2021

Objective

To compare overall survival (OS) and disease‐free survival (DFS) between sentinel lymph node biopsy (SNB) and elective neck dissection (END) in the surgical management of cT1‐2N0 oral cavity squamous cell carcinoma (OCSCC).

Methods

English full‐text articles were searched in PubMed and Embase on May 9, 2021. Articles had to compare SNB with END in cT1‐T2N0 OCSCC patients; report hazard ratios (HRs), Kaplan–Meier curves, or P‐values with total number of events for survival outcomes; be from a clinical trial, cohort, or case–control study. Two reviewers reviewed articles and a third settled disagreements. Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines and the Risk of Bias in Non‐randomized Studies of Interventions tool and revised Cochrane risk‐of‐bias tool for randomized trials were used. The generic inverse variance method with a random‐effect model was used for meta‐analysis.

Results

Ten studies, five retrospective, three prospective, and two randomized controlled trials, were included (total number of patients [n] = 10,498, END n = 9102, SNB n = 1396). No significant differences were found in OS (HR = 0.92; 95% confidence interval [CI]: 0.65–1.31) or DFS (HR = 0.70; 95% CI: 0.41–1.20). Heterogeneity was not detected in pooled OS analysis (P = .18; I2 = 30%), but was in pooled DFS analysis (P = .003; I2 = 66%).

Conclusions

No statistically significant differences in OS or DFS were observed between SNB and END in cT1‐2N0 OCSCC, suggesting that SNB might be an alternative to END in the management of early‐stage, clinically node‐negative OCSCC. Laryngoscope, 132:989–998, 2022
Impact of Hospital Volume on Outcomes Following Head and Neck Cancer Surgery and Flap Reconstruction
Authors: Madrigal Josef , Mukdad Laith , Han Albert Y. , Tran Zachary , Benharash Peyman , St. John Maie A. , Blackwell Keith E.
Published: October 2021

Objective/Hypothesis

Utilization of flaps for reconstruction of large head and neck cancer (HNCA) defects has become more prevalent. The present study aimed to assess the impact of center experience as measured by annual hospital caseload on mortality, major complications, resource utilization, and 90‐day readmissions following HNCA resection with flap reconstruction.

Study Design

Non‐Randomized Controlled Cohort Study.

Methods

All adult patients undergoing elective HNCA resection with flap reconstruction were identified utilizing the 2010 to 2018 Nationwide Readmissions Database. Hospitals were subsequently classified as low‐, medium‐, or high‐volume based on annual institutional surgical caseload tertiles. Multivariable regression models were implemented to assess the independent association of hospital volume with the outcomes of interest.

Results

Over the nine‐year study period, the proportion of HNCA resection with flap reconstruction gradually increased (12.8% in 2010 vs. 17.3% in 2018, P < .001). Although increasing hospital volume did not alter the odds of mortality, patients treated at high‐volume centers were less likely to experience both surgical (adjusted odds ratio [AOR] 0.81, 95% confidence interval [CI] 0.67–0.97, P = .025) and medical complications (AOR 0.70, 95% CI 0.57–0.85, P < .001). Furthermore, these patients had shorter hospitalizations (−2.1 days, 95% CI −2.7 to −1.4 days, P < .001) and decreased costs (−$8,100, 95% CI −11,400 to −4,700, P < .001) compared to counterparts at low‐volume centers. However, hospital volume did not impact 90‐day readmissions.

Conclusion

Patients undergoing HNCA resection with flap reconstruction at high‐volume centers were less likely to experience surgical and medical complications while incurring shorter hospitalizations and lower costs. Implementation of volume standards may be appropriate to improve outcomes in this surgical population.

Level of Evidence

3 Laryngoscope, 132:1381–1387, 2022
Does salinization impact long‐term Daphnia assemblage dynamics? Evidence from the sediment egg bank in a small hard‐water lake
Authors: Wersebe Matthew J. , Edlund Mark B. , Weider Lawrence J.
Published: October 2021

Salinization of freshwater ecosystems threatens global aquatic biodiversity. There is a need for studies that follow populations in situ during salinization to understand the effects on species and ecosystems. We follow 170 years of Daphnia dynamics in the sediment ephippia archive of a small urban lake near St. Paul, Minnesota, to characterize effects of severe recent salinization on lake Daphnia. We found modest changes in the flux of ephippia in this lake; all three key Daphnia functional groups remained in the assemblage throughout the period of salinization. Reconstruction of the size distribution of Daphnia pulicaria demonstrated a consistent increase in body size in opposition to the expected trajectory during salinization. Our findings highlight that in hard‐water lakes, the effects of salinization are nuanced and require further investigation to better understand overall impacts of salinization on hard‐water lake Daphnia assemblages.
Desorption electrospray ionization mass spectrometry imaging in discovery and development of novel therapies
Authors: Soudah Terese , Zoabi Amani , Margulis Katherine
Published: October 2021

Desorption electrospray ionization mass spectrometry imaging (DESI‐MSI) is one of the least specimen destructive ambient ionization mass spectrometry tissue imaging methods. It enables rapid simultaneous mapping, measurement, and identification of hundreds of molecules from an unmodified tissue sample. Over the years, since its first introduction as an imaging technique in 2005, DESI‐MSI has been extensively developed as a tool for separating tissue regions of various histopathologic classes for diagnostic applications. Recently, DESI‐MSI has also emerged as a versatile technique that enables drug discovery and can guide the efficient development of drug delivery systems. For example, it has been increasingly employed for uncovering unique patterns of in vivo drug distribution, the discovery of potentially treatable biochemical pathways, revealing novel druggable targets, predicting therapeutic sensitivity of diseased tissues, and identifying early tissue response to pharmacological treatment. These and other recent advances in implementing DESI‐MSI as the tool for the development of novel therapies are highlighted in this review.
Gradient estimates for parabolic problems with Orlicz growth and discontinuous coefficients
Authors: Oh Jehan , Ok Jihoon
Published: October 2021

We obtain Calderón‐Zygmund‐type estimates for parabolic equations with Orlicz growth, where nonlinearities involved in the equations may be discontinuous for the space and time variables. In addition, we consider parabolic systems with the Uhlenbeck structure.
Compact triple‐mode bandpass filters based on single perturbed substrate integrated waveguide cavity using coaxial feed
Authors: Feng Yulin , Fang Shaojun , Zhou Leitao , Zhang Qiuyi , Xu Zhixia
Published: October 2021

A compact triple‐mode bandpass filter (BPF) based on a modified rectangular substrate integrated waveguide (SIW) cavity is presented. The perturbation of the dominant mode (TE101) and the third resonance mode (TE102) are realized by two metalized vias in order to keep the first three resonant modes evenly distributed in the passband. Using this strategy, we can control both bandwidth and finite‐transmission zero (FTZ). The bandwidth of BPF can be controlled by simply changing the diameter of the metalized vias. Coaxial excitation is used to achieve a parallel coupling with small external quality factor, resulting in a wideband response. The proposed triple‐mode SIW BPF also has an FTZ, which is decided by the angle between two feeds. In order to verify the proposed strategy, two samples with a center frequency of 5.5 GHz have been designed and manufactured.
A new emittance selection system to maximize beam transmission for low‐energy beams in cyclotron‐based proton therapy facilities with gantry
Authors: Maradia Vivek , Meer David , Weber Damien Charles , Lomax Antony John , Schippers Jacobus Maarten , Psoroulas Serena
Published: October 2021

Purpose

In proton therapy, the potential of using high‐dose rates in the cancer treatment is being explored. High‐dose rates could improve efficiency and throughput in standard clinical practice, allow efficient utilization of motion mitigation techniques for moving targets, and potentially enhance normal tissue sparing due to the so‐called FLASH effect. However, high‐dose rates are difficult to reach when lower energy beams are applied in cyclotron‐based proton therapy facilities, because they result in large beam sizes and divergences downstream of the degrader, incurring large losses from the cyclotron to the patient position (isocenter). In current facilities, the emittance after the degrader is reduced using circular collimators; however, this does not provide an optimal matching to the acceptance of the following beamline, causing a low transmission for these energies. We, therefore, propose to use a collimation system, asymmetric in both beam size and divergence, resulting in symmetric emittance in both beam transverse planes as required for a gantry system. This new emittance selection, together with a new optics design for the following beamline and gantry, allows a better matching to the beamline acceptance and an improvement of the transmission.

Methods

We implemented a custom method to design the collimator sizes and shape required to select high emittance, to be transported by the following beamline using new beam optics (designed with TRANSPORT) to maximize acceptance matching. For predicting the transmission in the new configuration (new collimators + optics), we used Monte Carlo simulations implemented in BDSIM, implementing a model of PSI Gantry 2 which we benchmarked against measurements taken in the current clinical scenario (circular collimators + clinical optics).

Results

From the BDSIM simulations, we found that the new collimator system and matching beam optics results in an overall transmission from the cyclotron to the isocenter for a 70 MeV beam of 0.72%. This is an improvement of almost a factor of 6 over the current clinical performance (0.13% transmission). The new optics satisfies clinical beam requirements at the isocenter.

Conclusions

We developed a new emittance collimation system for PSI's PROSCAN beamline which, by carefully selecting beam size and divergence asymmetrically, increases the beam transmission for low‐energy beams in current state‐of‐the‐art cyclotron‐based proton therapy gantries. With these improvements, we could predict almost 1% transmission for low‐energy beams at PSI's Gantry 2. Such a system could easily be implemented in facilities interested in increasing dose rates for efficient motion mitigation and FLASH experiments alike.
XIORT‐MC: A real‐time MC‐based dose computation tool for low‐ energy X‐rays intraoperative radiation therapy
Authors: Ibáñez Paula , Villa‐Abaunza Amaia , Vidal Marie , Guerra Pedro , Graullera Sergio , Illana Carlos , Udías José Manuel
Published: October 2021

Purpose

The INTRABEAM system is a miniature accelerator for low‐energy X‐ray Intra‐Operative Radiation Therapy (IORT), and it could benefit from a fast and accurate dose computation tool. With regards to accuracy, dose computed with Monte Carlo (MC) simulations are the gold standard, however, they require a large computational effort and consequently they are not suitable for real‐time dose planning. This work presents a comparison of the implementation on Graphics Processing Unit (GPU) of two different dose calculation algorithms based on MC phase‐space (PHSP) information to compute dose distributions for the INTRABEAM device within seconds and with the accuracy of realistic MC simulations.

Methods

The MC‐based algorithms we present incorporate photoelectric, Compton and Rayleigh effects for the interaction of low‐energy X‐rays. XIORT‐MC (X‐ray Intra‐Operative Radiation Therapy Monte Carlo) includes two dose calculation algorithms; a Woodcock‐based MC algorithm (WC‐MC) and a Hybrid MC algorithm (HMC), and it is implemented in CPU and in GPU. Detailed MC simulations have been generated to validate our tool in homogeneous and heterogeneous conditions with all INTRABEAM applicators, including three clinically realistic CT‐based simulations. A performance study has been done to determine the acceleration reached with the code, in both CPU and GPU implementations.

Results

Dose distributions were obtained with the HMC and the WC‐MC and compared to standard reference MC simulations with more than 95% voxels fulfilling a 7%‐0.5 mm gamma evaluation in all the cases considered. The CPU‐HMC is 100 times more efficient than the reference MC, and the CPU‐WC‐MC is about 50 times more efficient. With the GPU implementation, the particle tracking of the WC‐MC is faster than the HMC, with the extraction of the particle's information from the PHSP file taking a major part of the time. However, thanks to the variance reduction techniques implemented in the HMC, up to 400 times less particles are needed in the HMC to reach the same level of noise than the WC‐MC. Therefore, in our implementation for INTRABEAM energies, the HMC is about 1.3 times more efficient than the WC‐MC in an NVIDIA GeForce GTX 1080 Ti card and about 5.5 times more efficient in an NVIDIA GeForce RTX 3090. Dose with noise below 5% has been obtained in realistic situations in less than 5 s with the WC‐MC and in less than 0.5 s with the HMC.

Conclusions

The XIORT‐MC is a dose computation tool designed to take full advantage of modern GPUs, making possible to obtain MC‐grade accurate dose distributions within seconds. Its high speed allows a real‐time dose calculation that includes the realistic effects of the beam in voxelized geometries of patients. It can be used as a dose‐planning tool in the operating room during a XIORT treatment with any INTRABEAM device.
Single‐shell NODDI using dictionary‐learner‐estimated isotropic volume fraction
Authors: Faiyaz Abrar , Doyley Marvin , Schifitto Giovanni , Zhong Jianhui , Uddin Md Nasir
Published: October 2021

Neurite orientation dispersion and density imaging (NODDI) enables the assessment of intracellular, extracellular, and free water signals from multi‐shell diffusion MRI data. It is an insightful approach to characterize brain tissue microstructure. Single‐shell reconstruction for NODDI parameters has been discouraged in previous studies caused by failure when fitting, especially for the neurite density index (NDI). Here, we investigated the possibility of creating robust NODDI parameter maps with single‐shell data, using the isotropic volume fraction (fISO) as a prior. Prior estimation was made independent of the NODDI model constraint using a dictionary learning approach. First, we used a stochastic sparse dictionary‐based network (DictNet), which is trained with data obtained from in vivo and simulated diffusion MRI data, to predict fISO. In single‐shell cases, the mean diffusivity and raw T2 signal with no diffusion weighting (S0) was incorporated in the dictionary for the fISO estimation. Then, the NODDI framework was used with the known fISO to estimate the NDI and orientation dispersion index (ODI). The fISO estimated using our model was compared with other fISO estimators in the simulation. Further, using both synthetic data simulation and human data collected on a 3 T scanner (both high‐quality HCP and clinical dataset), we compared the performance of our dictionary‐based learning prior NODDI (DLpN) with the original NODDI for both single‐shell and multi‐shell data. Our results suggest that DLpN‐derived NDI and ODI parameters for single‐shell protocols are comparable with original multi‐shell NODDI, and the protocol with b = 2000 s/mm2 performs the best (error ~ 5% in white and gray matter). This may allow NODDI evaluation of studies on single‐shell data by multi‐shell scanning of two subjects for DictNet fISO training.
Probabilistic learning on manifolds (PLoM) with partition
Authors: Soize Christian , Ghanem Roger
Published: October 2021

The probabilistic learning on manifolds (PLoM) introduced in 2016 has solved difficult supervised problems for the “small data” limit where the numberNof points in the training set is small. Many extensions have since been proposed, making it possible to deal with increasingly complex cases. However, the performance limit has been observed and explained for applications for whichNis very small and for which the dimension of the diffusion‐map basis is close toN. For these cases, we propose a novel extension based on the introduction of a partition in independent random vectors. We take advantage of this development to present improvements of the PLoM such as a simplified algorithm for constructing the diffusion‐map basis and a new mathematical result for quantifying the concentration of the probability measure in terms of a probability upper bound. The analysis of the efficiency of this extension is presented through two applications.
Analysis and mitigation of nonuniform soiling distribution on utility‐scale photovoltaic systems
Authors: Micheli Leonardo , Fernández Eduardo F. , Fernández‐Solas Álvaro , Bessa João Gabriel , Almonacid Florencia
Published: October 2021

The present paper evaluates the soiling losses of a 3.25‐MW photovoltaic (PV) system installed in central Chile, 200 km north of Santiago, and analyzes the nonuniform soiling deposition between the various strings for a period of 3 years. A robust methodology is developed to extract, in the most systematic way, 142 reliable soiling profiles from the 256 PV power time series recorded on site. It is found that, if unmitigated, soiling would reduce the annual DC energy generation by 8%, with a factor of 2× between the losses of the most and least affected strings. Most of the losses are registered on the edges of the plant, closer to traffic and unpaved roads. The most soiling intense months are in summer, result of the infrequent rainfalls and of the high concentrations of suspended particles that characterize this season. The revenues and the costs of different manual cleaning frequencies are evaluated and compared to identify the optimal soiling mitigation strategy for this site. Three cleanings per year are found to return the highest profits for the economic conditions considered in this study. However, a sensitivity analysis shows how different cleaning costs and electricity prices would affect the soiling mitigation strategy. In addition, in light of the nonuniform soiling deposition distribution, the possibility of cleaning only selected strings rather than the full PV plant is discussed.
Near surface defects: Cause of deficit between internal and external open‐circuit voltage in solar cells
Authors: Sood Mohit , Urbaniak Aleksander , Kameni Boumenou Christian , Weiss Thomas Paul , Elanzeery Hossam , Babbe Finn , Werner Florian , Melchiorre Michele , Siebentritt Susanne
Published: October 2021

Interface recombination in a complex multilayered thin‐film solar structure causes a disparity between the internal open‐circuit voltage (VOC,in), measured by photoluminescence, and the external open‐circuit voltage (VOC,ex), that is, a VOC deficit. Aspirations to reach higher VOC,ex values require a comprehensive knowledge of the connection between VOC deficit and interface recombination. Here, a near‐surface defect model is developed for copper indium di‐selenide solar cells grown under Cu‐excess conditions. These cell show the typical signatures of interface recombination: a strong disparity between VOC,in and VOC,ex, and extrapolation of the temperature dependent q·VOC,ex to a value below the bandgap energy. Yet, these cells do not suffer from reduced interface bandgap or from Fermi‐level pinning. The model presented is based on experimental analysis of admittance and deep‐level transient spectroscopy, which show the signature of an acceptor defect. Numerical simulations using the near‐surface defects model show the signatures of interface recombination without the need for a reduced interface bandgap or Fermi‐level pinning. These findings demonstrate that the VOC,in measurements alone can be inconclusive and might conceal the information on interface recombination pathways, establishing the need for complementary techniques like temperature dependent current–voltage measurements to identify the cause of interface recombination in the devices.