bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental analysis on dynamic characteristics of unsaturated sericite schist residual soil controlled by different factors
Authors: Li Chongyang , Zhang Qingwen
Published: June 2021

Taking sericite schist residual soil widely distributed along Dalin Railway as the research object, the resonance column test of sericite schist residual soil in unsaturated state was carried out, and the dynamic shear modulus Gd under different water content, dry density and consolidation confining pressure in small strain range (10−6 < γ
d < 10−4) was studied. The test results show that water content has a great influence on dynamic shear modulus, followed by dry density and consolidation confining pressure. Gd increases non-linearly with the increase of water cut, and there is a certain critical water cut that makes Gd reach the maximum, and then Gd gradually declines with the increase of water cut; D ∼ γ
d curves tend to overlap under high confining pressure and high water content. Under the same dynamic shear strain amplitude, Gd increases with the increase of dry density. Under different consolidation confining pressures, the increasing of Gd follow-up shear strain γd tends to decrease.
Application and Seismic Analysis of changing masonry structure into bottom frame structure
Authors: Dou Pengfei , Xu Xinsheng , Liu Yujiao
Published: June 2021

In order to meet the requirements of people for the use of large space, the masonry structure building is underpinned, the load-bearing wall of the building is removed, and the underpinning beam is constructed to replace the original load-bearing wall to bear the upper load, the bottom masonry structure is transformed into a large space frame structure. Based on the analysis of two different underpinning methods, this paper selects the structural underpinning method according to their advantages and disadvantages, and takes an example as an example to summarize the construction of underpinning beam structure first. Then the main construction methods and matters needing attention of the underpinning technology for removing the load-bearing wall in the construction process, so as to provide a certain basis for the future construction of the structure. Through the displacement loading method, the bearing capacity of frame beam and underpinning beam is analyzed, and the data are processed, and the advantages and disadvantages of underpinning beam and frame beam under load are obtained.
Influencing factors of measurement results of polished stone values of coarse aggregates
Authors: Dou Guangwu , Zhou Yishu , Zhang Yaojun , Liu Yue , Guo Hongbo , Zhang Jinning
Published: June 2021

The polished stone value (PSV) of a coarse aggregate indicates its ability to resist the polishing action of tires. In the measurement tests of PSV of coarse aggregates, due to the complicated process, artificial factors or instrumental performances may cause measurement deviations. In order to explore the influences of instrumental factors, based on the features and working principle of a pendulum friction coefficient tester, the main influencing factors were firstly analyzed and then experimentally verified through measuring PSV of andesite and basalt. With the one-variable linear regression method, the testing data were fitted in order to determine the variations of the PSV of coarse aggregates with the hardness of rubber strip used in the slider block and the axial deformation distance of the slider block corresponding to the maximum positive static pressure on the tested surface. With the increase in the hardness of rubber strip, the measured PSV increased. With the increase in the axial deformation distance of slider block corresponding to the maximum positive static pressure on the tested surface, the measured PSV decreased. The quantitative analysis of the factors affecting PSV can improve its determination accuracy.
Research on the application of consumer UAV in river and lake demarcation
Authors: Zhu Wei , Zhang Zhuanzhuan , Wang Ze
Published: June 2021

The delimitation of rivers and lakes is the basis for clarifying the management scope and protection scope of river courses and lakes, and implementing the property right system of natural resources and effective management of natural ecological resources. The development of UAV low altitude photogrammetry technology provides a strong support for river and lake demarcation in terms of cost, efficiency and quality. In this paper, the reliability of the data in the test area is verified by selecting the project test area, and the feasibility of the application of consumer UAVs in the river and lake demarcation project is obtained, which provides some technical reference for the application of consumer UAVs in engineering projects.
Spatial-temporal variation of NDVI and its responses to precipitation in the upper of Heihe from 2000 to 2019
Authors: Xuefei  , Liujie  , Guotao Dong , Huazhu Xue
Published: June 2021

As the direct result of climate change, Spatio-temporal variation of vegetation cover is an important index in regional ecological change. Based on Google Earth Engine, MODIS-NDVI and precipitation of TRMM from 2000 to 2019 were extracted. Trend analysis method and PCCs were applied to explore the different scales temporal and spatial change of NDVI and the relationship between NDVI and precipitation in the upper of Heihe River Basin. It was found that the annual change of vegetation increased slowly in the study area, and correlation of vegetation NDVI with precipitation are insignificant. On month scale, the vegetation change was cyclical, there was a noticeable increase from June to September, but from November to next February, the vegetation coverage was the lowest, the change of precipitation had the similar variation pattern, and there was a strong positive correlation between precipitation and NDVI. In terms of spatial change, the NDVI rose generally from northwest to southeast, vegetation coverage in northwest was improved.
A New Method for Estimating High Frequency Attenuation Parameter of Kappa
Authors: Ji Yuan , Haiyun Wang
Published: June 2021

The Fourier amplitude spectrum of acceleration will drop rapidly in the high frequency range. Anderson and Hough quantitatively studied the attenuation law of the acceleration Fourier spectrum above the corner frequency, and proposed the high-frequency attenuation parameter Kappa ( ) to describe this phenomenon. It has important applications in the field of engineering earthquakes, and is widely used by seismologists and engineers in the work of ground motion simulation and attenuation relations. Based on the Anderson method, this paper proposed a method of first smoothing the Fourier acceleration spectrum with a 0.4 Hz Parzen window and then fitting the solution value. The Fukushima earthquake data from Japan’s KiK-net seismic network on February 13, 2021 was used to verify the reliability of the method. The results showed that when the width of the Parzen window was set to 0.4 Hz, the calculation accuracy of the value was effectively improved.
Application progress of digital technology in the protection of Chinese traditional villages
Authors: Wu Yajie , Huang Chunhua
Published: June 2021

As a new trend of cultural heritage protection, digital technology has brought opportunities and challenges to the detection, protection and development of traditional villages. First, this article introduces the specific application of digital technology in the three stages of data collection, information processing and display and dissemination, and constructs the corresponding integrated application diagram, then summarizes the implementation obstacles in the protection process. Finally, a prospect is made for the development of digital protection of traditional villages. The results show that digital technology can provide a strong data foundation and flexible processing methods for the storage, restoration, display and dissemination of traditional village protection, and promote the transformation of single technology to multiple integrated applications.
Deep and shallow slice knots in 4-manifolds
Authors: Klug Michael , Ruppik Benjamin
Published: June 2021

We consider slice disks for knots in the boundary of a smooth compact 4-manifold

X

4

X^{4}

. We call a knot

K
⊂
∂
X

K \subset \partial X

deep slice in

X
X

if there is a smooth properly embedded

2
2

-disk in

X
X

with boundary

K
K

, but

K
K

is not concordant to the unknot in a collar neighborhood

∂
X
×

I

\partial X \times {I}

of the boundary.

We point out how this concept relates to various well-known conjectures and give some criteria for the nonexistence of such deep slice knots. Then we show, using the Wall self-intersection invariant and a result of Rohlin, that every 4-manifold consisting of just one 0- and a nonzero number of 2-handles always has a deep slice knot in the boundary.

We end by considering 4-manifolds where every knot in the boundary bounds an embedded disk in the interior. A generalization of the Murasugi-Tristram inequality is used to show that there does not exist a compact, oriented

4
4

-manifold

V
V

with spherical boundary such that every knot

K
⊂

S

3

=
∂
V

K \subset {S}^{3} = \partial V

is slice in

V
V

via a null-homologous disk.
Loss of basigin expression in uterine cells leads to subfertility in female mice
Authors: Li Kailiang , Li Quanxi , Bashir Shah Tauseef , Bany Brent M , Nowak Romana A
Published: June 2021

Basigin (BSG) is a transmembrane glycoprotein involved in cell proliferation, angiogenesis, and tissue remodeling. BSG has been shown to be essential for male and female reproduction although little is known about its role in normal uterine function. To study the potential function of BSG in the female reproductive tract, we generated mice with conditional knockout of Bsg in uterine cells using progesterone receptor-Cre and hypothesized that BSG is required for normal pregnancy in mice. Fertility study data showed that the conditional knockout mice had significantly reduced fertility compared to controls. Ovarian function of the conditional knockout mice appeared normal with no difference in the number of superovulated oocytes collected or in serum progesterone levels between the conditional knockout and the control mice. Uterine tissues collected at various times of gestation showed increased abnormalities in implantation, decidualization, placentation, and parturition in the conditional knockout mice. Uterine cross sections on Day 5 of pregnancy showed implantation failure and abnormal uterine epithelial differentiation in a large proportion of the conditional knockout mice. There was a compromised decidual response to artificial decidualization stimuli and decreased mRNA and protein levels for decidualization genes in the uteri of the conditional knockout mice. We also observed altered protein expression of monocarboxylate transporter 1 (MCT1), as well as impaired angiogenesis in the conditional knockout uteri compared to the controls. These results support that BSG is required for successful pregnancy through its functions in implantation and decidualization.
Thinking Beyond Extremism: A Critique of Counterterrorism Research on Right-Wing Nationalist and Far-Right Social Movements
Authors: Tetrault Justin Everett Cobain
Published: June 2021

Researchers increasingly use counterterrorism approaches to explain how right-wing groups mobilize as a growing social movement. I reveal the limits of security-oriented research for studying right-wing movements using a semi-ethnographic case study of the Canadian yellow vests. Dominant security narratives paint Canada’s yellow vests as foremost a criminogenic and violent white nationalist movement. My findings, however, suggest that these groups (1) fetishize law and order; and (2) attempt to maintain legitimacy by rejecting vigilantism and policing extreme messaging. Fixating on the ‘extremism’ and criminal risks of right-wing movements can distort analysis and exaggerate their distance from mainstream culture. My data include over 40 h of participant-observation at 20 right-wing rallies and 35 interviews with current leaders and members of on-the-ground nationalist groups.
Giant axonal neuropathy: cross-sectional analysis of a large natural history cohort
Authors: Bharucha-Goebel Diana X , Norato Gina , Saade Dimah , Paredes Eduardo , Biancavilla Victoria , Donkervoort Sandra , Kaur Rupleen , Lehky Tanya , Fink Margaret , Armao Diane , Gray Steven J , Waite Melissa , Debs Sarah , Averion Gilberto , Hu Ying , Zein Wadih M , Foley A Reghan , Jain Minal , Bönnemann Carsten G
Published: June 2021

Giant axonal neuropathy (GAN) is an ultra-rare autosomal recessive, progressive neurodegenerative disease with early childhood onset that presents as a prominent sensorimotor neuropathy and commonly progresses to affect both the PNS and CNS. The disease is caused by biallelic mutations in the GAN gene located on 16q23.2, leading to loss of functional gigaxonin, a substrate specific ubiquitin ligase adapter protein necessary for the regulation of intermediate filament turnover.

Here, we report on cross-sectional data from the first study visit of a prospectively collected natural history study of 45 individuals, age range 3–21 years with genetically confirmed GAN to describe and cross-correlate baseline clinical and functional cohort characteristics.

We review causative variants distributed throughout the GAN gene in this cohort and identify a recurrent founder mutation in individuals with GAN of Mexican descent as well as cases of recurrent uniparental isodisomy. Through cross-correlational analysis of measures of strength, motor function and electrophysiological markers of disease severity, we identified the Motor Function Measure 32 to have the strongest correlation across measures and age in individuals with GAN. We analysed the Motor Function Measure 32 scores as they correspond to age and ambulatory status. Importantly, we identified and characterized a subcohort of individuals with a milder form of GAN and with a presentation similar to Charcot–Marie–Tooth disease. Such a clinical presentation is distinct from the classic presentation of GAN, and we demonstrate how the two groups diverge in performance on the Motor Function Measure 32 and other functional motor scales. We further present data on the first systematic clinical analysis of autonomic impairment in GAN as performed on a subset of the natural history cohort.

Our cohort of individuals with genetically confirmed GAN is the largest reported to date and highlights the clinical heterogeneity and the unique phenotypic and functional characteristics of GAN in relation to disease state. The present work is designed to serve as a foundation for a prospective natural history study and functions in concert with the ongoing gene therapy trial for children with GAN.
Context Sensitivity across Multiple Time scales with a Flexible Frequency Bandwidth
Authors: Regev Tamar I , Markusfeld Geffen , Deouell Leon Y , Nelken Israel
Published: June 2021

Everyday auditory streams are complex, including spectro-temporal content that varies at multiple timescales. Using EEG, we investigated the sensitivity of human auditory cortex to the content of past stimulation in unattended sequences of equiprobable tones. In 3 experiments including 82 participants overall, we found that neural responses measured at different latencies after stimulus onset were sensitive to frequency intervals computed over distinct timescales. Importantly, early responses were sensitive to a longer history of stimulation than later responses. To account for these results, we tested a model consisting of neural populations with frequency-specific but broad tuning that undergo adaptation with exponential recovery. We found that the coexistence of neural populations with distinct recovery rates can explain our results. Furthermore, the adaptation bandwidth of these populations depended on spectral context—it was wider when the stimulation sequence had a wider frequency range. Our results provide electrophysiological evidence as well as a possible mechanistic explanation for dynamic and multiscale context-dependent auditory processing in the human cortex.
Time to Viral Rebound After Interruption of Modern Antiretroviral Therapies
Authors: Li Jonathan Z , Aga Evgenia , Bosch Ronald J , Pilkinton Mark , Kroon Eugène , MacLaren Lynsay , Keefer Michael , Fox Lawrence , Barr Liz , Acosta Edward , Ananworanich Jintanat , Coombs Robert , Mellors John W , Landay Alan L , Macatangay Bernard , Deeks Steven , Gandhi Rajesh T , Smith Davey M
Published: June 2021

Background

Development of human immunodeficiency virus (HIV) remission strategies requires precise information on time to HIV rebound after treatment interruption, but there is uncertainty regarding whether modern antiretroviral therapy (ART) regimens and timing of ART initiation may affect this outcome.

Methods

AIDS Clinical Trials Group (ACTG) A5345 enrolled individuals who initiated ART during chronic or early HIV infection and on suppressive ART for ≥2 years. Participants underwent carefully monitored antiretroviral interruption. ART was restarted upon 2 successive viral loads ≥1000 copies/mL. We compared participants of A5345 with participants of 6 historic ACTG treatment interruption studies.

Results

Thirty-three chronic-treated and 12 early-treated participants interrupted ART with evaluable time to viral rebound. Median time to viral rebound ≥1000 HIV RNA copies/mL was 22 days. Acute retroviral rebound syndrome was diagnosed in 9% of the chronic-treated and none of the early-treated individuals. All participants of the historic studies were on older protease inhibitor-based regimens, whereas 97% of A5345 participants were on integrase inhibitor-based ART. There were no differences in the timing of viral rebound comparing A5345 versus historic studies. In a combined analysis, a higher percentage of early-treated participants remained off ART at posttreatment interruption week 12 (chronic vs early: 2% vs 9%, P = .0496). One chronic-treated and one early-treated A5345 participant remained off ART for >24 weeks. All participants resuppressed after ART reinitiation.

Conclusions

Early ART initiation, using either older or newer ART regimens, was associated with a significant delay in the time to HIV rebound after ART interruption, lowering the barrier for HIV remission.
Impact of chronic kidney disease on the pharmacodynamic and pharmacokinetic effects of ticagrelor in patients with diabetes mellitus and coronary artery disease
Authors: Franchi Francesco , Rollini Fabiana , Been Latonya , Maaliki Naji , Abou Jaoude Patrick , Rivas Andrea , Zhou Xuan , Jia Sida , Briceno Maryuri , Lee Chang Hoon , Pineda Andres M , Suryadevara Siva , Soffer Daniel , Zenni Martin M , Bass Theodore A , Angiolillo Dominick J
Published: June 2021

Aims

Patients with diabetes mellitus (DM) and chronic kidney disease (CKD) are at increased risk of atherothrombotic events. Ticagrelor reduces ischaemic events compared to clopidogrel, with the greatest risk reduction in patients with both DM and CKD. How CKD status affects the pharmacodynamic (PD) and pharmacokinetic (PK) profiles of different ticagrelor maintenance dose regimens in patients with DM is unknown.

Methods and results

In this randomized, crossover study, patients with DM on treatment with dual antiplatelet therapy (aspirin and clopidogrel) were stratified according to CKD status and randomized to ticagrelor 90 or 60 mg bid. PK/PD assessments were performed at baseline, after 7–10 days of ticagrelor (peak and trough), and after 7–10 days of alternative ticagrelor regimen (peak and trough). PK assessments included plasma concentrations of ticagrelor and its major metabolite. PD assessments included vasodilator-stimulated phosphoprotein (VASP)–platelet reactivity index (PRI), VerifyNow P2Y12, and light transmittance aggregometry (LTA). A total of 92 patients with DM (CKD, n = 44; non-CKD, n = 48) were randomized. Levels of platelet reactivity were lower with the 90 mg compared with the 60 mg ticagrelor dose, which was statistically significant in non-CKD but not in CKD patients for most PD measures. There were no significant differences in the primary endpoint (trough levels of VASP–PRI following ticagrelor 90 mg dosing) between cohorts (31 ± 20 vs. 25 ± 14; P = 0.105). VerifyNow and LTA provided similar findings. PK assessments tracked PD profiles showing increased plasma concentrations of ticagrelor and its major metabolite in CKD compared to non-CKD patients.

Conclusion

In patients with DM, although ticagrelor maintenance dose regimens (60 and 90 mg) yield potent P2Y12 inhibition, levels of platelet reactivity tended to be higher and subject to broader variability in non-CKD compared with CKD patients.

Clinical trial registration

http://www.clinicaltrials.gov Unique Identifier: NCT02539160.
Did giraffe cardiovascular evolution solve the problem of heart failure with preserved ejection fraction?
Authors: Natterson-Horowitz Barbara , Baccouche Basil M , Head Jennifer Mary , Shivkumar Tejas , Bertelsen Mads Frost , Aalkjær Christian , Smerup Morten H , Ajijola Olujimi A , Hadaya Joseph , Wang Tobias
Published: June 2021

The evolved adaptations of other species can be a source of insight for novel biomedical innovation. Limitations of traditional animal models for the study of some pathologies are fueling efforts to find new approaches to biomedical investigation. One emerging approach recognizes the evolved adaptations in other species as possible solutions to human pathology. The giraffe heart, for example, appears resistant to pathology related to heart failure with preserved ejection fraction (HFpEF)—a leading form of hypertension-associated cardiovascular disease in humans. Here, we postulate that the physiological pressure-induced left ventricular thickening in giraffes does not result in the pathological cardiovascular changes observed in humans with hypertension. The mechanisms underlying this cardiovascular adaptation to high blood pressure in the giraffe may be a bioinspired roadmap for preventive and therapeutic strategies for human HFpEF.
Matching Methods for Confounder Adjustment: An Addition to the Epidemiologist’s Toolbox
Authors: Greifer Noah , Stuart Elizabeth A
Published: June 2021

Propensity score weighting and outcome regression are popular ways to adjust for observed confounders in epidemiologic research. Here, we provide an introduction to matching methods, which serve the same purpose but can offer advantages in robustness and performance. A key difference between matching and weighting methods is that matching methods do not directly rely on the propensity score and so are less sensitive to its misspecification or to the presence of extreme values. Matching methods offer many options for customization, which allow a researcher to incorporate substantive knowledge and carefully manage bias/variance trade-offs in estimating the effects of nonrandomized exposures. We review these options and their implications, provide guidance for their use, and compare matching methods with weighting methods. Because of their potential advantages over other methods, matching methods should have their place in an epidemiologist’s methodological toolbox.
COVID-19 mRNA Vaccination Generates Greater Immunoglobulin G Levels in Women Compared to Men
Authors: Demonbreun Alexis R , Sancilio Amelia , Velez Matt E , Ryan Daniel T , Pesce Lorenzo , Saber Rana , Vaught Lauren A , Reiser Nina L , Hsieh Ryan R , D’Aquila Richard T , Mustanski Brian , McDade Thomas W , McNally Elizabeth M
Published: June 2021

We investigated whether the antibody response to coronavirus disease 2019 (COVID-19) mRNA vaccination is similar in women and men. In a community cohort without prior COVID-19, first vaccine dose produced higher immunoglobulin G (IgG) levels and percent inhibition of spike-ACE2 receptor binding, a surrogate measure of virus neutralization, in women compared to men (7.0 µg/mL, 51.6% vs 3.3 µg/mL, 36.4%). After 2 doses, IgG levels remained significantly higher for women (30.4 µg/mL) compared to men (20.6 µg/mL), while percent inhibition was similar (98.4% vs 97.7%). Sex-specific antibody response to mRNA vaccination informs future efforts to understand vaccine protection and side effects.
Toxicological Relevance of Pregabalin in Heroin Users: A Two-Year Postmortem Population Study
Authors: Nahar Limon K , Murphy Kevin , Paterson Sue
Published: June 2021

Pregabalin (PGL) is a gabapentinoid used to treat epilepsy, neuropathic pain and generalized anxiety disorder. PGL is also misused by heroin users as it enhances the effects of heroin. While it is thought those who misuse PGL take it in amounts greater than the recommended therapeutic dose, it is unknown whether there is a significant difference between the amounts of PGL used by heroin users compared to non-heroin users. This study hypothesized that the PGL concentrations in postmortem (PM) samples taken from heroin users positive for PGL would be higher than those in non-heroin users. Between 1 January 2016 and 31 December 2016, a routine drug screen and a specific screen for PGL were carried out on femoral-vein bloods from 3,750 PM Coroners’ cases. Of the cases screened, 354 were heroin users, of which 264 cases were negative for gabapentinoids and therefore used as the control-heroin-user group. PGL was positive in 229 cases, of which 69 were heroin users and 160 were non-heroin users. On comparing the PGL concentrations, statistically higher concentrations were observed in the heroin users compared to non-heroin users (P = 0.002). There was no correlation between the concentrations of PGL and morphine (from heroin) in the heroin users (P = 0.95), and the amount of heroin (morphine) consumed was not dependant on whether PGL was consumed or not (P = 0.98). The prevalence of anti-depressants, benzodiazepines, methadone and non-heroin-related opioids was seen to be significantly higher in heroin users that were positive for PGL than the control-heroin users (P = < 0.001 for all drugs). This study suggests that heroin users are using greater amounts of PGL compared to non-heroin users; however, the magnitude of the difference in use may not be sufficient to conclude that heroin users are at substantially greater risk of PGL toxicity compared to non-heroin users. Results indicate that heroin users who take PGL are more likely to use multiple depressant drugs, hence increasing the risk of multi-drug toxicity and death in this population.
Hyperbaric Oxygen and Mortality in Burns With Inhalation Injury: A Study of the National Burn Repository
Authors: Nygaard Rachel M , Endorf Frederick W
Published: June 2021

Mortality in burn injury is primarily influenced by three factors: age, percent burn (%TBSA), and presence of inhalation injury. Numerous modalities have been tried in an attempt to treat those patients with burns and inhalation injury, including the use of hyperbaric oxygen (HBO). The aim of our study was to find the national prevalence of HBO for burns with inhalation injury, and whether HBO influenced mortality in these often severely injured patients. This retrospective study used the National Burn Repository (NBR) to identify hospital admissions of patients with both cutaneous burn and inhalation injuries. After applying exclusion criteria, a total of 13,044 patients were identified. Variables included in the multivariate regression analysis included age, sex, race, payer, mechanism of burn injury, TBSA group, total procedure number, mechanical ventilator days, and treatment with HBO. The main outcome variable was mortality. Of the 13,044 patients, 67 had HBO therapy. The HBO patients were older (mean age 51.7 vs 42.8 years, P < .001), but had smaller burns and thus a similar Baux score (66.6 vs 65.2, P = .661). The HBO patients had a higher mortality (29.9% vs 17.5%, P = .01). On multivariate regression analysis, HBO was an independent predictor of mortality (odds ratio = 2.484, P = .004). Other significant predictors of mortality included age, black race, Medicaid or uninsured patients, and %TBSA. The use of HBO for patients with burns and inhalation injury is uncommon in this database. It is unclear whether that reflects low prevalence or if individual centers do not all impute HBO into the NBR. For those patients in this database, HBO is an independent predictor of mortality. It can be difficult to determine the severity of inhalation injury in the NBR, so those patients receiving HBO could theoretically have more severe inhalation injury.
Do Low-Risk Patients With Dyspepsia Need a Gastroscopy? Use of Gastroscopy for Otherwise Healthy Patients With Dyspepsia
Authors: Halasz Jennifer B , Burak Kelly W , Dowling Shawn K , Murray Brenna , Williams Jennifer , Misra Tarun , Veldhuyzen van Zanten Sander J , Kaplan Gilaad G , Swain Mark , Novak Kerri L
Published: June 2021

Background

Choosing Wisely Canada (CWC) recommends not to perform gastroscopy for dyspepsia in otherwise healthy adults less than 55 years of age (2014). The aim of this study was to evaluate the use of gastroscopy in a young, healthy population with uncomplicated dyspepsia.

Methods

A retrospective review of gastroscopies completed during 3-month periods in 2015, 2016, and 2017 identified all patients undergoing gastroscopy for the primary indication of dyspepsia. Low-risk patients for dyspepsia were defined as adults, aged 18 to 54 years without alarm symptoms, comorbidities and/or abnormal imaging findings or laboratory values. Gastroscopy and pathology reports were reviewed to identify clinically actionable findings. Clinical outcomes were followed to December 31, 2018 including gastroenterology referrals, emergency room visitation and hospitalization.

Results

Among 1358 patients having a gastroscopy for dyspepsia, 480 (35%) were low-risk patients. Sixteen patients 3.3% (16/480) had a clinically actionable result found on gastroscopy or biopsy. No malignant lesions were detected. Low-risk patients were followed up for an average of 2.75 years, 8% (39/480) visited the emergency department (ED), 1% (3/480) of patients were admitted to hospital and 12% (59/480) of patients were re-referred for a dyspepsia-related concern.

Interpretation

A high rate of low yield, high cost, invasive endoscopic investigations were performed in this population of otherwise healthy patients under age 55 years. These data suggest limited uptake of current recommendations against the routine use of gastroscopy to investigate dyspepsia.
Professor Arnold L. (Arny) Demain's historical position in the rise of industrial microbiology and biotechnology
Authors: Vandamme Erick J
Published: June 2021

This perspective text focuses on the pivotal role and historical position that the late Prof. Arnold L. (Arny) Demain has taken since the 1950s in the rise and impact of the field of industrial microbiology and biotechnology. His drive toward academic research with industrial potential—first at Merck & Co. and later at MIT—, his feeling for establishing cordial personal contacts with his students and postdocs (Arny's Army) and his ability for worldwide networking are outlined here, intertwined with the author's personal experiences and impressions. His scientific output is legendary as to research papers, comprehensive reviews, books, and lectures at conferences worldwide. Some of his research experiences in industry and academia are mentioned in a historical context as well as his relentless efforts to advocate the importance and impact of industrial microbiology and biotechnology as an essential green technology for our planet Earth.
Evaluation of the Residual Efficacy of Actellic300 CS in Simple Huts in Central Ethiopia
Authors: Dugassa Sisay , Mekonnen Sileshi , Muthee Peter W , Peter Rose , Zinyengere David , Feyasa Merga B , Sievert Kai
Published: June 2021

Indoor residual spraying (IRS) is one of the key vector control tools with a long history of use in the world. Ethiopia has set a goal to eliminate malaria from selected districts mainly by applying IRS and the distribution of long-lasting insecticidal nets. IRS is applied in low malaria transmission districts which are epidemic prone and in districts with high malaria transmission. Ethiopia uses insecticides that are recommended by World Health Organization; these insecticides must also be registered in Ethiopia. The registration of new and potential products requires confirmatory, local efficacy trials to be performed. Actellic 300CS, now registered, is one of such potential product. Actellic 300CS showed average mortalities of 99.6%, 99.6%, and 99.0% on the sprayed surfaces in the experimental huts, the top, middle, and bottom sections, respectively during the first 6 mo of the study period. Beyond 6 mo, (7, 8, and 9 mo) follow-up, mortalities for the top, middle, and bottom sections were 85.2%, 86.3%, and 85.2%, respectively. The results showed that the residual efficacy of Actellic 300CS was up to 9 mo with the first 6 mo exhibiting mortalities of greater than 99% while the next 3 mo showed mortalities exceeding 85%. Actellic 300CS was effective against fully susceptible laboratory-reared Anopheles arabiensis on all four surface types (rough, smooth, dung, and painted surfaces) tested in this study and could be used as one of the chemical insecticides of choice for the ongoing IRS programs in Ethiopia.
Effects of pulse precipitation on soil organic matter mineralization in forests: spatial variation and controlling factors
Authors: Jiang Zhaoxia , Bian Hongfeng , Xu Li , Li Mingxu , He Nianpeng
Published: June 2021

Aims

Pulse effects of precipitation cause soil organic matter to rapidly decompose and release CO2 in a short period. The pulse effects of precipitation are important for ecosystem C cycling and soil C balance, although their spatial variation in forest soils and the underlying mechanisms remain unclear.

Methods

Soil samples (0–10 cm) from 22 typical forest ecosystems in eastern China were used, to investigate the effects of simulated pulse precipitation on soil microbial respiration rates (Rs). We simulated pulsed precipitation to reach 65% water-holding capacity, the Rs was measured on a minute scale for 48 h.

Important Findings

Precipitation pulses can cause a rapid 1.70–38.12-fold increase in the rate of mineralized decomposing organic matter. Maximum Rs (Rs-soil-max), cumulative Rs (ARs-soil) and the time taken to arrive at the maximal Rs (TRs-soil-max) were significant differences among different soil samples. Furthermore, the pulse effects in different climate zones were significantly different. Rs-soil-max (11.701 µg C g−1soil h−1) and ARs-soil (300.712 µg C g−1 soil) were the highest in the mid-temperate zone. Soil chemical properties (total C and, N, pH and oxidation–reduction potential) and soil fractions were strongly correlated with the pulse effects in forest soils, but soil microbes contributed less. Our findings demonstrated that the pulse effects increase forest soil carbon emissions in the short term at a regional scale, and identified the factors with the greatest influence on this change. These findings help guide future studies on the C cycles of forest ecosystems and regulating ecosystem C cycles.
Leaf traits from stomata to morphology are associated with climatic and edaphic variables for dominant tropical forest evergreen oaks
Authors: Lin Yutong , Kuang Luhui , Tang Songbo , Mou Zhijian , Phillips Oliver L , Lambers Hans , Liu Zhanfeng , Sardans Jordi , Peñuelas Josep , Lai Yuan , Lin Mingxian , Chen Dexiang , Kuang Yuanwen
Published: June 2021

Aims

Understanding variation and coordination of leaf traits at multiscales along elevational gradients can help predict the likely responses of dominant species to climate change. We seek to determine the extent to which variation in leaf stomatal, anatomical and morphological traits is associated with environmental factors, and whether ecological strategies of Cyclobalanopsis species shift with elevations.

Methods

In a tropical forest landscape in Jianfengling, South China, we determined leaf traits related to stomata, anatomy and morphology of six evergreen oak species (Cyclobalanopsis bambusaefolia, C. hui, C. patelliformis, C. fleuryi, C. tiaoloshanica and C. phanera) along a long elevational gradient (400–1400 m above sea level).

Important Findings

We found that stomatal density and stomatal pore index increased, whereas spongy mesophyll thickness to leaf thickness ratios decreased, significantly with elevation. The leaf area and leaf dry matter content increased and decreased, respectively, with elevation. Variations in stomatal, anatomical and morphological traits were mainly correlated to the mean annual temperature, mean annual sum precipitation and soil pH. At low and high elevations, the oak species exhibited strong stress tolerance combined with competition strategy, while they shifted toward more clearly the competitive strategy at intermediate elevations. And the changes in soil phosphorus concentration and soil pH along the elevation may drive the shift of ecological strategy. The results showed that the dominant oak species in tropical forests respond to environmental change by modulating traits at multiple levels, from that of the individual cell, through tissue and up to the whole leaf scale.
Unique Pathogen Peptidomes Facilitate Pathogen-Specific Selection and Specialization of MHC Alleles
Authors: Özer Onur , Lenz Tobias L
Published: June 2021

A key component of pathogen-specific adaptive immunity in vertebrates is the presentation of pathogen-derived antigenic peptides by major histocompatibility complex (MHC) molecules. The excessive polymorphism observed at MHC genes is widely presumed to result from the need to recognize diverse pathogens, a process called pathogen-driven balancing selection. This process assumes that pathogens differ in their peptidomes—the pool of short peptides derived from the pathogen’s proteome—so that different pathogens select for different MHC variants with distinct peptide-binding properties. Here, we tested this assumption in a comprehensive data set of 51.9 Mio peptides, derived from the peptidomes of 36 representative human pathogens. Strikingly, we found that 39.7% of the 630 pairwise comparisons among pathogens yielded not a single shared peptide and only 1.8% of pathogen pairs shared more than 1% of their peptides. Indeed, 98.8% of all peptides were unique to a single pathogen species. Using computational binding prediction to characterize the binding specificities of 321 common human MHC class-I variants, we investigated quantitative differences among MHC variants with regard to binding peptides from distinct pathogens. Our analysis showed signatures of specialization toward specific pathogens especially by MHC variants with narrow peptide-binding repertoires. This supports the hypothesis that such fastidious MHC variants might be maintained in the population because they provide an advantage against particular pathogens. Overall, our results establish a key selection factor for the excessive allelic diversity at MHC genes observed in natural populations and illuminate the evolution of variable peptide-binding repertoires among MHC variants.
Functional interplay of histone lysine 2-hydroxyisobutyrylation and acetylation in Arabidopsis under dark-induced starvation
Authors: Zheng Lanlan , Li Chen , Ma Xueping , Zhou Hanlin , Liu Yuan , Wang Ping , Yang Huilan , Tamada Yosuke , Huang Ji , Wang Chunfei , Hu Zhubing , Wang Xuening , Wang Guodong , Li Haihong , Hu Juntao , Liu Xiaoyun , Zhou Chao , Zhang Yonghong
Published: June 2021

Lysine 2-hydroxyisobutyrylation (Khib) is a novel type of histone acylation whose prevalence and function in plants remain unclear. Here, we identified 41 Khib sites on histones in Arabidopsis thaliana, which did not overlap with frequently modified N-tail lysines (e.g. H3K4, H3K9 and H4K8). Chromatin immunoprecipitation-sequencing (ChIP-seq) assays revealed histone Khib in 35% of protein-coding genes. Most Khib peaks were located in genic regions, and they were highly enriched at the transcription start sites. Histone Khib is highly correlated with acetylation (ac), particularly H3K23ac, which it largely resembles in its genomic and genic distribution. Notably, co-enrichment of histone Khib and H3K23ac correlates with high gene expression levels. Metabolic profiling, transcriptome analyses, and ChIP-qPCR revealed that histone Khib and H3K23ac are co-enriched on genes involved in starch and sucrose metabolism, pentose and glucuronate interconversions, and phenylpropanoid biosynthesis, and help fine-tune plant response to dark-induced starvation. These findings suggest that Khib and H3K23ac may act in concert to promote high levels of gene transcription and regulate cellular metabolism to facilitate plant adaption to stress. Finally, HDA6 and HDA9 are involved in removing histone Khib. Our findings reveal Khib as a conserved yet unique plant histone mark acting with lysine acetylation in transcription-associated epigenomic processes.
Characteristics of patients ≥10 years of age with diffuse intrinsic pontine glioma: a report from the International DIPG/DMG Registry
Authors: Erker Craig , Lane Adam , Chaney Brooklyn , Leary Sarah , Minturn Jane E , Bartels Ute , Packer Roger J , Dorris Kathleen , Gottardo Nicholas G , Warren Katherine E , Broniscer Alberto , Kieran Mark W , Zhu Xiaoting , White Peter , Dexheimer Phillip J , Black Katie , Asher Anthony , DeWire Mariko , Hansford Jordan R , Gururangan Sridharan , Nazarian Javad , Ziegler David S , Sandler Eric , Bartlett Allison , Goldman Stewart , Shih Chie-Schin , Hassall Tim , Dholaria Hetal , Bandopadhayay Pratiti , Samson Yvan , Monje Michelle , Fisher Paul G , Dodgshun Andrew , Parkin Sarah , Chintagumpala Murali , Tsui Karen , Gass David , Larouche Valerie , Broxson Emmett , Garcia Lombardi Mercedes , Wang Stacie Shiqi , Ma Jie , Hawkins Cynthia , Hamideh Dima , Wagner Lars , Koschmann Carl , Fuller Christine , Drissi Rachid , Jones Blaise V , Leach James , Fouladi Maryam
Published: June 2021

Background

Diffuse intrinsic pontine gliomas (DIPG) generally occur in young school-age children, although can occur in adolescents and young adults. The purpose of this study was to describe clinical, radiological, pathologic, and molecular characteristics in patients ≥10 years of age with DIPG enrolled in the International DIPG Registry (IDIPGR).

Methods

Patients ≥10 years of age at diagnosis enrolled in the IDIPGR with imaging confirmed DIPG diagnosis were included. The primary outcome was overall survival (OS) categorized as long-term survivors (LTS) (≥24 months) or short-term survivors (STS) (<24 months).

Results

Among 1010 patients, 208 (21%) were ≥10 years of age at diagnosis; 152 were eligible with a median age of 12 years (range 10-26.8). Median OS was 13 (2-82) months. The 1-, 3-, and 5-year OS was 59.2%, 5.3%, and 3.3%, respectively. The 18/152 (11.8%) LTS were more likely to be older (P < .01) and present with longer symptom duration (P < .01). Biopsy and/or autopsy were performed in 50 (33%) patients; 77%, 61%, 33%, and 6% of patients tested had H3K27M (H3F3A or HIST1H3B), TP53, ATRX, and ACVR1 mutations/genome alterations, respectively. Two of 18 patients with IDH1 testing were IDH1-mutant and 1 was a LTS. The presence or absence of H3 alterations did not affect survival.

Conclusion

Patients ≥10 years old with DIPG have a median survival of 13 months. LTS present with longer symptom duration and are likely to be older at presentation compared to STS. ATRX mutation rates were higher in this population than the general DIPG population.
Redo craniotomy or bevacizumab for symptomatic steroid-refractory true or pseudoprogression following IMRT for glioblastoma
Authors: Cook Theresa A , Jayamanne Dasantha T , Wheeler Helen R , Wong Matthew H F , Parkinson Jonathon F , Cook Raymond J , Kastelan Marina A , Cove Nicola J , Brown Christopher , Back Michael F
Published: June 2021

Background

There is minimal evidence to support decision making for symptomatic steroid-refractory pseudoprogression or true progression occurring after intensity-modulated radiation therapy (IMRT) for glioblastoma (GBM). This study audited the survival outcome of patients managed with redo craniotomy (RedoSx) or bevacizumab (BEV) for steroid-refractory mass effect after IMRT for GBM.

Methods

Patients with GBM managed between 2008 and 2019 with the EORTC-NCIC Protocol were entered into a prospective database. Patients with symptomatic steroid-refractory mass effect within 6 months of IMRT managed with either RedoSx or BEV were identified for analysis. For the primary endpoint of median overall survival (OS) postintervention, outcome was analyzed in regards to potential prognostic factors, and differences between groups were assessed by log-rank analyses.

Results

Of the 399 patients managed with the EORTC-NCIC Protocol, 78 required an intervention within 6 months of IMRT completion for either true or pseudoprogression (49 with RedoSx and 29 with BEV). Subsequently, 20 of the 43 patients managed with RedoSx when BEV was clinically available, required salvage with BEV within 6 months after RedoSx. Median OS postintervention was 8.7 months (95% CI: 7.84-11.61) for the total group; and 8.7 months (95% CI: 6.8-13.1) for RedoSx and 9.4 months (95% CI: 7.8-13.6) for BEV (P = .38). Subsequent use of BEV in RedoSx patients was not associated with improved survival compared with RedoSx alone (P = .10). Age, time from IMRT, and ECOG performance status were not associated with OS. In the RedoSx patients, immunohistochemical features such as Ki-67% reduction correlated with survival. The presence of pure necrosis and residual tumor cells only had improved survival compared with the presence of gross tumor (P < .001).

Conclusions

At time of symptomatic steroid-refractory true or pseudoprogression following IMRT for GBM, BEV was equivalent to RedoSx in terms of OS. Pseudoprogression with residual cells at RedoSx was not associated with worse outcome compared to pure necrosis.
X-ray observations of accretion disks
Authors: Inoue Hajime
Published: June 2021

Present understandings of accretion disks based on X-ray observations are reviewed. The main focus is on observational properties of accretion disks around black holes in X-ray binaries and their phenomenological interpretations. Since there are several excellent reviews on black hole binaries already, we here pick up a limited number of important works which introduced key observational clues which widen and/or deepen the understanding of the accretion disks, recalling histories of X-ray observations of binary X-ray sources with a number of X-ray astronomy satellites successively launched from the United States, European countries, and Japan. We at certain points compare some observational evidence from black hole binaries with similar phenomena observed from binaries with a weakly magnetized neutron star, to clarify the basic nature of accretion disks. We also try to understand accretion environments in active galactic nuclei by applying what we have learned from the black hole binaries to them.