bluuebunny/crossref_metadata_2025 huggingface dataset:
Using a Reinforced Stapler Decreases the Incidence of Postoperative Pancreatic Fistula After Distal Pancreatectomy: A Systematic Review and Meta‐Analysis
Authors: Oweira Hani , Mazotta Alessandro , Mehrabi Arianeb , Reissfelder Christoph , Rahbari Nuh , Betzler Alexander , Elhadedy Hazem , Soubrane Olivier , Chaouch Mohamed Ali
Published: May 2022

Background

There is no consensus on the pancreatic transection during distal pancreatectomy (DP) to reduce postoperative pancreatic fistula (POPF). This meta‐analysis aimed to evaluate the effects of a reinforced stapler on the postoperative outcomes of DP.

Methods

We systematically searched electronic databases and bibliographic reference lists in The PubMed/MEDLINE, Google Scholar, Cochrane Library's Controlled Trials Registry and Database of Systematic Reviews, Embase, and Scopus. Review Manager Software was used for pooled estimates.

Results

Seven eligible studies published between 2007 and 2021 were included with 553 patients (267 patients in the reinforced stapler group and 286 patients in the standard stapler group). The reinforced stapler reduced the POPF grade B and C (OR = 0.33; 95% CI [0.19, 0.57], p < 0.01). There was no difference between the reinforced stapler group and standard stapler group in terms of mortality rate (OR = 0.39; 95% CI [0.04, 3.57], p = 0.40), postoperative haemorrhage (OR = 0.53; 95% CI [0.20, 1.43], p = 0.21), and reoperation rate (OR = 0.91; 95% CI [0.40, 2.06], p = 0.82).

Conclusions

Reinforced stapling in DP is safe and seems to reduce POPF grade B/C with similar mortality rates, postoperative bleeding, and reoperation rate. The protocol of this systematic review with meta‐analysis was registered in PROSPERO (ID: CRD42021286849).
Risk prediction of CMV reactivation after allogeneic stem cell transplantation using five non-HLA immunogenetic polymorphisms
Authors: Vallejo Miren , Muñiz Paula , Kwon Mi , Solán Laura , Bailén Rebeca , Carbonell Diego , Chicano María , Suárez-González Julia , Catalán Pilar , Bellón José María , Triviño Juan Carlos , Dorado Nieves , Gallardo David , Díez-Martín José Luis , Ramírez Natalia , Martínez-Laperche Carolina , Buño Ismael
Published: May 2022

Despite advances in the understanding of the pathophysiology of cytomegalovirus (CMV) infection, it remains as one of the most common infectious complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The aim of this study was to determine the genotype of cytokines and chemokines in donor and recipient and their association with CMV reactivation. Eighty-five patients receiving an allo-HSCT from an HLA-identical sibling donor were included in the study. Fifty genes were selected for their potential role in the pathogenesis of CMV infection. CMV DNAemia was evaluated until day 180 after allo-HSCT. CMV reactivation was observed in 51/85 (60%) patients. Of the 213 genetic variants selected, 11 polymorphisms in 7 different genes (CXCL12, IL12A, KIR3DL1, TGFB2, TNF, IL1RN, and CD48) were associated with development or protection from CMV reactivation. A predictive model using five of such polymorphisms (CXCL12 rs2839695, IL12A rs7615589, KIR3DL1 rs4554639, TGFB2 rs5781034 for the recipient and CD48 rs2295615 for the donor) together with the development of acute GVHD grade III/IV improved risk stratification of CMV reactivation. In conclusion, the data presented suggest that the screening of five polymorphisms in recipient and donor pre-transplantation could help to predict the individual risk of CMV infection development after HLA-identical allo-HSCT.
Anterior chamber enhancement predicts optic nerve infiltration in retinoblastoma
Authors: Deike-Hofmann Katerina , von Lampe Paula , Eerikaeinen Maija , Ting Saskia , Schlüter Sabrina , Schlemmer Heinz-Peter , Bechrakis Nikolaos E. , Forsting Michael , Radbruch Alexander
Published: May 2022

Objectives

As described recently, intravenously injected gadolinium-based contrast agent (GBCA) penetrates into the anterior eye chamber (AC) and is drained from the retina to the distal optic nerve (ON) along perivascular spaces, which serves retinal homeostasis and was termed the orbital glymphatic system (GS). Independently, AC enhancement predicted ON infiltration, a major risk factor for advanced retinoblastoma (RB), in a small RB patient cohort. We aimed to review the supposed imaging biomarker for ON infiltration in a large RB cohort and with respect to the recently described orbital GS.

Methods

This IRB–approved retrospective single-center study encompassed 539 orbital MRIs performed with an orbital coil and with the children under general anesthesia. Differences of signal intensity ratios (∆SIRs) of the AC to the lens were determined between non-contrast and GBCA–enhanced T1-weighted images and were correlated with histopathologic presence of ON infiltration.

Results

∆SIR of the RB eye was an independent, significant predictor for ON invasion in multivariate analysis with adjustment for tumor size (p < 0.05) and increased with infiltration level.

Conclusions

GBCA enhancement of the AC predicts ON infiltration. This might be caused by impairment of the orbital glymphatic system, which is supposed to clear toxic metabolites from the retina to the postlaminar ON. In RB with ON infiltration, this efflux path is likely to be inhibited, which is supposed to result in disturbed retinal homeostasis, release of vascular endothelial growth factor, and iris neovascularization, which increases penetration of GBCA into the AC.

Key Points

• Infiltration of the optic nerve can be predicted by anterior chamber enhancement after intravenous MRI contrast agent administration.

• Increased anterior chamber enhancement in retinoblastoma with optic nerve infiltration might result from dysfunction of the orbital glymphatic system with disturbance of retinal homeostasis and consecutive iris neovascularization.
Background parenchymal enhancement in contrast-enhanced MR imaging suggests systemic effects of intrauterine contraceptive devices
Authors: Huck Luisa Charlotte , Truhn Daniel , Wilpert Caroline , Zanderigo Eloisa , Raaff Vanessa , Dethlefsen Ebba , Bode Maike , Kuhl Christiane Katharina
Published: May 2022

Objectives

Levonorgestrel-releasing intrauterine contraceptive devices (LNG-IUDs) are designed to exhibit only local hormonal effects. There is an ongoing debate on whether LNG-IUDs can have side effects similar to systemic hormonal medication. Benign background parenchymal enhancement (BPE) in dynamic contrast–enhanced (DCE) MRI has been established as a sensitive marker of hormonal stimulation of the breast. We investigated the association between LNG-IUD use and BPE in breast MRI to further explore possible systemic effects of LNG-IUDs.

Methods

Our hospital database was searched to identify premenopausal women without personal history of breast cancer, oophorectomy, and hormone replacement or antihormone therapy, who had undergone standardized DCE breast MRI at least twice, once with and without an LNG-IUD in place. To avoid confounding aging-related effects on BPE, half of included women had their first MRI without, the other half with, LNG-IUD in place. Degree of BPE was analyzed according to the ACR categories. Wilcoxon-matched-pairs signed-rank test was used to compare the distribution of ACR categories with vs. without LNG-IUD.

Results

Forty-eight women (mean age, 46 years) were included. In 24/48 women (50% [95% CI: 35.9–64.1%]), ACR categories did not change with vs. without LNG-IUDs. In 23/48 women (48% [33.9–62.1%]), the ACR category was higher with vs. without LNG-IUDs; in 1/48 (2% [0–6%]), the ACR category was lower with vs. without LNG-IUDs. The change of ACR category depending on the presence or absence of an LNG-IUD proved highly significant (p < 0.001).

Conclusion

The use of an LNG-IUD can be associated with increased BPE in breast MRI, providing further evidence that LNG-IUDs do have systemic effects.

Key Points

• The use of levonorgestrel-releasing intrauterine contraceptive devices is associated with increased background parenchymal enhancement in breast MRI.

• This suggests that hormonal effects of these devices are not only confined to the uterine cavity, but may be systemic.

• Potential systemic effects of levonorgestrel-releasing intrauterine contraceptive devices should therefore be considered.
Identification and Characterization of Bacillus subtilis B9: A Diazotrophic Plant Growth-Promoting Endophytic Bacterium Isolated from Sugarcane Root
Authors: Di Yi-ning , Kui Ling , Singh Pratiksha , Liu Lu-feng , Xie Lin-yan , He Li-lian , Li Fu-sheng
Published: May 2022

Plant endophytic microorganisms, which can enhance plant growth and resistance to biotic and abiotic stresses, are untapped resources with large potential applications for crop production. However, the endophytic community is influenced by multiple factors, such as host genetics, the environment, and other microbes. Thus, it is important to characterize well-adapted endophytes from native crops. We isolated 43 endophytic bacteria from sugarcane cultivar Yunzhe-99-91. All these 43 isolates were examined in vitro for nitrogenase activity and the ability to dissolve phosphorus and produce siderophore. One of these strains, B9, identified as Bacillussubtilis and showed maximum plant growth promotion, was selected for detailed studies. B9 promoted the production of organic acids such as propionic acid, acetic acid, malic acid and citric acid, and the production of phytohormones, including indole-3-acetic acid, cytokinin, 6-benzyladenine, and zeatin. Moreover, B9 significantly promoted the growth of sugarcane plantlets and increased the content of nitrogen, phosphorus, and potassium in the seedlings by 29.26%, 50.78%, and 15.49%, respectively. The photosynthetic rate, root development, and chlorophyll content were also improved with varying degrees compared to the non-inoculated control. The cotyledon and hypocotyl of sugarcane gems germinated faster when co-cultured with the B9 strain compared with control group. Colonization assay showed that B9 was mainly colonized in the roots, followed by the stems and leaves. In conclusion, the positive interaction between endophytic strain B9 and sugarcane may provide long-lasting benefits and a direction for developing and utilizing B9 as a biofertilizer for sugarcane cultivation to decrease fertilizer application.
Paediatric surgical trials, their fragility index, and why to avoid using it to evaluate results
Authors: Schröder Arne , Muensterer Oliver J. , Oetzmann von Sochaczewski Christina
Published: May 2022

Background

The fragility index has been gaining ground in the evaluation of comparative clinical studies. Many scientists evaluated trials in their fields and deemed them to be fragile, although there is no consensus on the definition of fragility. We aimed to calculate the fragility index and its permutations for paediatric surgical trials.

Methods

We searched pubmed for prospectively conducted paediatric surgical trials with intervention and control group without limitations and calculated their (reverse) fragility indices and respective quotients along with posthoc-power. Relationships between variables were evaluated using Spearman’s ρ. We also calculated S values by negative log transformation base-2 of P values.

Results

Of 516 retrieved records, we included 87. The median fragility index was 1.5 (interquartile range: 0–4) and the median reverse fragility index was 3 (interquartile range: 2–4), although they were statistically not different (Mood’s test: χ2 = 0.557, df = 1, P = 0.4556). P values and fragility indices were strongly inversely correlated (ρ = − 0.71, 95% confidence interval: − 0.53 to − 0.85, P < 0.0001), while reverse fragility indices were moderately correlated to P values (ρ = 0.5, 95% confidence interval: 0.37–0.62, P < 0.0001). A fragility index of 1 resulted from P values between 0.039 and 0.003, which resulted in S values between 4 and 8.

Conclusions

Fragility indices, reverse fragility indices, and their respective fragility quotients of paediatric surgical trials are low. The fragility index can be viewed as no more than a transformed P value with even more substantial limitations. Its inherent penalisation of small studies irrespective of their clinical relevance is particularly harmful for paediatric surgery. Consequently, the fragility index should be avoided.
Harnessing retinal phagocytes to combat pathological neovascularization in ischemic retinopathies?
Authors: Klotzsche-von Ameln Anne , Sprott David
Published: May 2022

Ischemic retinopathies (IR) are vision-threatening diseases that affect a substantial amount of people across all age groups worldwide. The current treatment options of photocoagulation and anti-VEGF therapy have side effects and are occasionally unable to prevent disease progression. It is therefore worthwhile to consider other molecular targets for the development of novel treatment strategies that could be safer and more efficient. During the manifestation of IR, the retina, normally an immune privileged tissue, encounters enhanced levels of cellular stress and inflammation that attract mononuclear phagocytes (MPs) from the blood stream and activate resident MPs (microglia). Activated MPs have a multitude of effects within the retinal tissue and have the potential to both counter and exacerbate the harmful tissue microenvironment. The present review discusses the current knowledge about the role of inflammation and activated retinal MPs in the major IRs: retinopathy of prematurity and diabetic retinopathy. We focus particularly on MPs and their secreted factors and cell–cell-based interactions between MPs and endothelial cells. We conclude that activated MPs play a major role in the manifestation and progression of IRs and could therefore become a promising new target for novel pharmacological intervention strategies in these diseases.
Effects of a narrative template on memory for the time of movie scenes: automatic reshaping is independent of consolidation
Authors: Frisoni Matteo , Di Ghionno Monica , Guidotti Roberto , Tosoni Annalisa , Sestieri Carlo
Published: May 2022

Memory for time is influenced by reconstructive processes, but the underlying mechanisms remain unclear. The present study investigated whether the effect of schematic prior knowledge on temporal memory for movie scenes, produced by the incomplete presentation (cut) of the movie at encoding, is modulated by cut position, retention interval, and task repetition. In a timeline positioning task, participants were asked to indicate when short video clips extracted from a previously encoded movie occurred on a horizontal timeline that represented the video duration. In line with previous findings, removing the final part of the movie resulted in a systematic underestimation of clips' position as a function of their proximity to the missing part. Further experiments demonstrate that the direction of this automatic effect depends on which part of the movie is deleted from the encoding session, consistent with the inferential structure of the schema, and does not depend on consolidation nor reconsolidation processes, at least within the present experimental conditions. We propose that the observed bias depends on the automatic influence of reconstructive processes on judgments about the time of occurrence, based on prior schematic knowledge.
On the Fine-grained Parameterized Complexity of Partial Scheduling to Minimize the Makespan
Authors: Nederlof Jesper , Swennenhuis Céline M. F.
Published: May 2022

We study a natural variant of scheduling that we call partial scheduling: in this variant an instance of a scheduling problem along with an integer k is given and one seeks an optimal schedule where not all, but only k jobs, have to be processed. Specifically, we aim to determine the fine-grained parameterized complexity of partial scheduling problems parameterized by k for all variants of scheduling problems that minimize the makespan and involve unit/arbitrary processing times, identical/unrelated parallel machines, release/due dates, and precedence constraints. That is, we investigate whether algorithms with runtimes of the type $$f(k)n^{{\mathcal {O}}(1)}$$

f

(
k
)

n

O
(
1
)

or $$n^{{\mathcal {O}}(f(k))}$$

n

O
(
f
(
k
)
)

exist for a function f that is as small as possible. Our contribution is two-fold: First, we categorize each variant to be either in $${\mathsf {P}}$$
P
, $${{\mathsf {N}}}{{\mathsf {P}}}$$

N
P

-complete and fixed-parameter tractable by k, or $${\mathsf {W}}[1]$$

W
[
1
]

-hard parameterized by k. Second, for many interesting cases we further investigate the runtime on a finer scale and obtain run times that are (almost) optimal assuming the Exponential Time Hypothesis. As one of our main technical contributions, we give an $${\mathcal {O}}(8^kk(|V|+|E|))$$

O
(

8
k

k
(
|
V
|

+

|
E
|
)
)

time algorithm to solve instances of partial scheduling problems minimizing the makespan with unit length jobs, precedence constraints and release dates, where $$G=(V,E)$$

G
=
(
V
,
E
)

is the graph with precedence constraints.
An enhanced Harris Hawk optimization algorithm for parameter estimation of single, double and triple diode photovoltaic models
Authors: Ramadan Abdelhady , Kamel Salah , Korashy Ahmed , Almalaq Abdulaziz , Domínguez-García Jose Luis
Published: May 2022

Due to the rapid development of photovoltaic (PV) system and spreading of its application, the accuracy of modeling of solar cells, as the main and basic element of PV systems, is gaining relevance. In this paper, an Enhanced Harris Hawk Optimization Algorithm (EHHO) is proposed and applied for estimating the required parameters of different PV models in an effective and accurate way. Harris Hawk Algorithm (HHO) is based on Hawks ways in hunting and catching their preys. The HHO utilizes two phases including exploration and exploitation. The main purpose of proposed enhancement is to improve the second phase of HHO. This enhancement is performed on the exploration phase by fluctuating toward or outward the best optimal solution using sine and cosine functions. Both conventional and proposed algorithms are applied for single, double and triple diode PV models. In order to test the applicability and robustness of proposed algorithm, it is applied for estimating the parameters of different real PV systems and compared with other recent optimization algorithms. The results show that the proposed EHHO is more accurate than conventional HHO and other algorithms.
A hierarchical hyper-heuristic for the bin packing problem
Authors: Guerriero Francesca , Saccomanno Francesco Paolo
Published: May 2022

This paper addresses the two-dimensional irregular bin packing problem, whose main aim is to allocate a given set of irregular pieces to larger rectangular containers (bins), while minimizing the number of bins required to contain all pieces. To solve the problem under study a dynamic hierarchical hyper-heuristic approach is proposed. The main idea of the hyper-heuristics is to search the space of low-level heuristics for solving computationally difficult problems. The proposed approach is “dynamic” since the low-level heuristic to be executed is chosen on the basis of the main characteristics of the instance to be solved. The term “hierarchical” is used to indicate the fact that the main hyper-heuristic can execute either simple heuristics or can run in a “recursive fashion” a hyper-heuristic. The developed solution strategy is evaluated empirically by performing extensive experiments on irregular packing benchmark instances. A comparison with the state-of-the-art approaches is also carried out. The computational results are very encouraging.
Human emotion recognition from EEG-based brain–computer interface using machine learning: a comprehensive review
Authors: Houssein Essam H. , Hammad Asmaa , Ali Abdelmgeid A.
Published: May 2022

Affective computing, a subcategory of artificial intelligence, detects, processes, interprets, and mimics human emotions. Thanks to the continued advancement of portable non-invasive human sensor technologies, like brain–computer interfaces (BCI), emotion recognition has piqued the interest of academics from a variety of domains. Facial expressions, speech, behavior (gesture/posture), and physiological signals can all be used to identify human emotions. However, the first three may be ineffectual because people may hide their true emotions consciously or unconsciously (so-called social masking). Physiological signals can provide more accurate and objective emotion recognition. Electroencephalogram (EEG) signals respond in real time and are more sensitive to changes in affective states than peripheral neurophysiological signals. Thus, EEG signals can reveal important features of emotional states. Recently, several EEG-based BCI emotion recognition techniques have been developed. In addition, rapid advances in machine and deep learning have enabled machines or computers to understand, recognize, and analyze emotions. This study reviews emotion recognition methods that rely on multi-channel EEG signal-based BCIs and provides an overview of what has been accomplished in this area. It also provides an overview of the datasets and methods used to elicit emotional states. According to the usual emotional recognition pathway, we review various EEG feature extraction, feature selection/reduction, machine learning methods (e.g., k-nearest neighbor), support vector machine, decision tree, artificial neural network, random forest, and naive Bayes) and deep learning methods (e.g., convolutional and recurrent neural networks with long short term memory). In addition, EEG rhythms that are strongly linked to emotions as well as the relationship between distinct brain areas and emotions are discussed. We also discuss several human emotion recognition studies, published between 2015 and 2021, that use EEG data and compare different machine and deep learning algorithms. Finally, this review suggests several challenges and future research directions in the recognition and classification of human emotional states using EEG.
Syntectonic magmatism and reactivation of collisional structures during late-Variscan shearing (SW Sardinia, Italy)
Authors: Secchi F. , Casini L. , Cifelli F. , Naitza S. , Carta E. , Oggiano G.
Published: May 2022

The Arbus igneous complex (SW Sardinia, Italy) represents a good example of a short time lived post-collisional composite pluton emplaced at shallow crustal level in the external zone of the Variscan chain. The pluton almost consists of granodiorite and leucogranite rock-suites emplaced at 304 ± 1 Ma within a main NW trending thrust separating the metamorphic wedge from the fold and thrust belt foreland. The pluton emplaced into a dilatational step over connecting two NW–SE dextral shear zones which belongs to a regional network of post-collisional strike-slip structures marking the transition from collision to post-collisional extension. The microstructure observed for quartz and K-feldspar confirms the lack of significant post-emplacement deformation, indicating only limited high-temperature sub-solidus recrystallization. Anisotropy of magnetic susceptivity data and field-structural analysis have been carried out to reconstruct the geometry of the pluton and the trajectories of magmatic flow in relation to regional deformation structures. Overall, the magmatic and the magnetic fabrics are broadly discordant with the metamorphic foliation of the country rocks, defining an EW trending elliptical asymmetric sill rooted in the SW quadrant. The reconstructed architecture combined to petrologic observation indicates that accretion of the pluton involved injection of multiple dykes through a sub-vertical feeder zone, combined to lateral flow of the roof controlled by inherited collisional structure. The duration of magmatic activity and the cooling history of the contact metamorphic aureole have been evaluated through a suite of 2D thermal models. All these observations, together with the available geochronological constraints are suggestive of very rapid construction of the pluton. The proposed emplacement model is fully consistent with the regional phase of strike-slip tectonics and widespread magmatism accommodating the large rotation of the Corsica-Sardinia block during the Carboniferous-Permian transition.
Semi-analytical Method for Modeling Wellbore Breakout Development
Authors: Setiawan Ngurah Beni , Zimmerman Robert W.
Published: May 2022

Borehole breakout initiation, progression, and stabilization are modeled using a semi-analytical method based on Melentiev’s graphical conformal mapping procedure, and Kolosov–Muskhelishvili complex stress potentials. The only input data required are the elastic moduli of the rock, the Coulomb strength parameters (cohesion and angle of internal friction), and the far-field stresses. The stresses around the borehole wall are computed, the region in which the rock has failed is then “removed”, creating a new borehole shape. This process is iterated until a shape is obtained for which the breakout will progress no further, and a stable state has been reached. This modeling shows that stresses around the flank of the breakout evolve so as to reduce the propensity for shear failure, which helps to explain why the breakout width remains relatively constant throughout the process, even as the breakout region deepens radially. The failed area around the borehole becomes smaller and more localized, as the breakout tip sharpens and deepens. Using the Mogi–Coulomb failure criterion, a good match is obtained between the modeled breakout geometry and the geometry observed by Herrick and Haimson in laboratory experiments on an Alabama limestone. The new method leads to a correlation between breakout geometry, rock strength properties, and in situ stress. The paper ends with a critical discussion of the possibility of inferring the in situ stress state from observed breakout geometries.
Pharmacological treatment of major depressive disorder according to severity in psychiatric inpatients: results from the AMSP pharmacovigilance program from 2001–2017
Authors: Seifert Johanna , Maier Hannah B. , Führmann Fabienne , Bleich Stefan , Stübner Susanne , Sieberer Marcel , Bernegger Xueqiong , Greil Waldemar , Schüle Cornelius , Toto Sermin , Grohmann Renate , Reinhard Matthias A.
Published: May 2022

The International Classification of Diseases (10th Version) categorizes major depressive disorder (MDD) according to severity. Guidelines provide recommendations for the treatment of MDD according to severity. Aim of this study was to assess real-life utilization of psychotropic drugs based on severity of MDD in psychiatric inpatients. Drug utilization data from the program “Drug Safety in Psychiatry” (German: Arzneimittelsicherheit in der Psychiatrie, AMSP) were analyzed according to the severity of MDD. From 2001 to 2017, 43,868 psychiatric inpatients with MDD were treated in participating hospitals. Most patients were treated with ≥ 1 antidepressant drug (ADD; 85.8% of patients with moderate MDD, 89.8% of patients with severe MDD, and 87.9% of patients with psychotic MDD). More severely depressed patients were more often treated with selective serotonin–norepinephrine reuptake inhibitors and mirtazapine and less often with selective serotonin reuptake inhibitors (p < 0.001 each). Use of antipsychotic drugs (APDs), especially second-generation APDs, increased significantly with severity (37.0%, 47.9%, 84.1%; p < 0.001 each). APD + ADD was the most used combination (32.8%, 43.6%, 74.4%), followed by two ADDs (26.3%, 29.3%, 24.9%). Use of lithium was minimal (3.3%, 6.1% ,7.1%). The number of psychotropic drugs increased with severity of MDD—patients with psychotic MDD had the highest utilization of psychotropic drugs (93.4%, 96.5%, 98.7%; p < 0.001). ADD monotherapy was observed to a lesser extent, even in patients with non-severe MDD (23.2%, 17.1%, 4.4%). Findings reveal substantial discrepancies between guideline recommendations and real-life drug utilization, indicating that guidelines may insufficiently consider clinical needs within the psychiatric inpatient setting.
Methionine-Based Radicals: Time Scales and Species
Authors: Neshchadin Dmytro , Kelterer Anne-Marie , Houée-Levin Chantal , Stadler Eduard , Spichty Martin , Gescheidt Georg
Published: May 2022

l-Methionine is an amino acid, which provides anti-oxidative properties. We report on radicals and radical cations being likely (short-lived) intermediates formed upon photo-oxidation reactions of methionine. In this context, we present photo-CIDNP experiments indicating that the character of the photooxidants is decisive for the observation of CIDNP effects based on methionine. Based on calculated hyperfine data and pKa values and on our experimental observations, we suggest that CIDNP polarizations are produced by an overlay of at least three geminal radical pairs, i.e., two α-thio carbon-centered radicals D· and G·, aminyl radical N·, and, possibly, 2c–3e radical cation SN.+ as short-lived reaction intermediates.
Use of buccal fat pad-derived stem cells cultured on bioceramics for repair of critical-sized mandibular defects in healthy and osteoporotic rats
Authors: Camacho-Alonso Fabio , Tudela-Mulero M. R. , Navarro J. A. , Buendía A. J. , Mercado-Díaz A. M.
Published: May 2022

Objective

To compare new bone formation in mandibular symphysis critical-sized bone defects (CSBDs) in healthy and osteoporotic rats filled with bioceramics (BCs) with or without buccal fat pad mesenchymal stem cells (BFPSCs).

Materials and methods

Thirty-two adult female Sprague–Dawley rats were randomized to two groups (n = 16 per group): group 1 healthy and group 2 osteoporotic (with bilateral ovariectomy). The central portion of the rat mandibular symphysis was used as a physiological CSBD. In each group, eight defects were filled with BC (hydroxyapatite 60% and β-tricalcium phosphate 40%) alone and eight with BFPSCs cultured on BC. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2).

Results

In both groups, CSBDs filled with BC + BFPSCs showed greater radiological bone union, BMD and histological bone union, and more VEGF and BMP-2 positivity, compared with CSBDs treated with BC alone at 4 and 8 weeks.

Conclusions

The application of BFPSCs cultured on BCs improves bone regeneration in CSBDs compared with BCs alone in healthy and osteoporotic rats.

Clinical relevance

Our results may aid bone regeneration of maxillofacial CSBDs of both healthy and osteoporotic patients, but further studies are necessary.
The Grow It! app—longitudinal changes in adolescent well-being during the COVID-19 pandemic: a proof-of-concept study
Authors: Dietvorst E. , Legerstee J. S. , Vreeker A. , Koval S. , Mens M. M. , Keijsers L. , Hillegers M. H. J.
Published: May 2022

Adolescent mental health and well-being have been adversely impacted by the COVID-19 pandemic. In this preregistered longitudinal study, we evaluated whether adolescents’ well-being improved after playing the multiplayer serious game app Grow It! During the first lockdown (May–June 2020), 1282 Dutch adolescents played the Grow It! app (age = 16.67, SD = 3.07, 68% girls). During the second lockdown (December–May 2020 onwards), an independent cohort of 1871 adolescents participated (age = 18.66, SD = 3.70, 81% girls). Adolescents answered online questionnaires regarding affective and cognitive well-being, depressive symptoms, anxiety, and impact of COVID-19 at baseline. Three to six weeks later, the baseline questionnaire was repeated and user experience questions were asked (N = 462 and N = 733 for the first and second cohort). In both cohorts, affective and cognitive well-being increased after playing the Grow It! app (t = − 6.806, p < 0.001; t = − 6.77, p < 0.001; t = − 6.12, p < 0.001; t = − 5.93, p < 0.001; Cohen’s d range 0.20–0.32). At the individual level, 41–53% of the adolescents increased in their affective or cognitive well-being. Adolescents with higher risk profiles (i.e., more depressive symptoms, lower atmosphere at home, and more COVID-19 impact) improved more strongly in their well-being. Positive user evaluations and app engagement were unrelated to changes in affective and cognitive well-being. This proof-of-concept study tentatively suggests that Grow It! supported adolescents during the pandemic.
Associations between adolescents watching pornography and poor mental health in three Swedish surveys
Authors: Svedin C. G. , Donevan M. , Bladh M. , Priebe G. , Fredlund C. , Jonsson L. S.
Published: May 2022

The aim of this study was to examine the association between watching pornography and poor mental health in three repeated cross-sectional surveys in Sweden (2004, 2009, 2014) among high school seniors (13,277 students) with an average age of 18 years. The same index questions concerning ever having watched pornography and the frequency of watching pornography during the last year were combined with three different measures of psychological health and background control variables in multiple logistic regression and forward stepwise logistic regression models. The repeated cross-sectional surveys did not find any consistent associations across years between poor mental health and ever having watched pornography or the frequency of watching pornography. Having watched deviant pornography (containing violence, children and/or animals) was associated with poor mental health among boys in two surveys but only in one survey among girls. Other characteristics, such as mother’s unemployment (especially boys), parenting style (especially high controlling parents among boys) and experiences of sexual abuse (especially penetrating abuse among girls), were more consistently and strongly associated to poor mental health across the three surveys. This study stresses the importance of controlling for multiple background variables when studying the association between watching pornography and mental health, since the association might primarily be explained by underlying confounding variables.
Tracing drought effects from the tree to the stand growth in temperate and Mediterranean forests: insights and consequences for forest ecology and management
Authors: Pretzsch Hans , del Río Miren , Grote Rüdiger , Klemmt Hans-Joachim , Ordóñez Cristóbal , Oviedo Felipe Bravo
Published: May 2022

How drought affects tree and stand growth is an old question, but is getting unprecedented relevance in view of climate change. Stress effects related to drought have been mostly studied at the individual tree level, mostly investigating dominant trees and using their responses as indicator for the impact at the stand level. However, findings at tree and stand level may differ, as the stand responses include interactions and feedbacks that may buffer or aggravate what is observed at the individual tree level. Here, we trace drought effects on growth and development from tree to the stand scale. Therefore, we analyse annually measured data from long-term experiments in temperate and Mediterranean forests. With this analysis, we aim to disclose how well results of dominant tree growth reflect stand-level behaviour, hypothesizing that drought resistance of dominant trees’ can strongly deviate from the overall sensitivity of the stand. First, we theoretically derive how drought responses at the stand level emerge from the tree-level behaviour, thereby considering that potential drought resistance of individual trees is modulated by acclimation and tree–tree interactions at the stand level and that the overall stress response at the stand level results from species-specific and size-dependent individual tree growth and mortality. Second, reviewing respective peer-reviewed literature (24 papers) and complementing findings by own measurements (22 experiments) from temperate and Mediterranean monospecific and mixed-species forests, we are able to reveal main causes for deviations of tree-level and stand-level findings regarding drought stress responses. Using a long-term experiment in Norway spruce (Picea abies (L.) KARST.) and European beech (Fagus sylvatica L.), we provide evidence that the species-dependent and size-dependent reactions matter and how the size–frequency distribution affects the scaling. We show by examples that tree-level derived results may overestimate growth losses by 25%. Third, we investigate the development of the growth dominance coefficient based on measurements gathered at the Bavarian forest climate stations. We show that drought changes stand biomass partitioning in favour of small trees, reduce social differentiation, and homogenize the vertical structure of forests. Finally, we discuss the drought-related consequences of the social class-specific growth reaction patterns for inventory and monitoring and highlight the importance of these findings for understanding site-specific stand dynamics, for forest modelling, and for silvicultural management.
Supply chain coordination under asymmetric information and partial vertical integration
Authors: Pishchulov Grigory , Richter Knut , Golesorkhi Sougand
Published: May 2022

Supply chain contracting is known to suffer from inefficiency in the presence of asymmetric information. Full vertical integration would eliminate the informational inefficiency but can be strategically undesirable. Yet today’s supply chain partnerships exhibit a certain degree of partial vertical integration via equity ties between the firms. Such governance forms received limited attention in supply chain research. Management literature suggests that partial vertical integration may help the firms to ease contracting problems by aligning their incentives, and thus improve the total surplus. We address this proposition by studying a model of a partially integrated supply chain in which the buyer holds an equity stake in the supplier. We adopt an operational perspective and investigate contracting between the firms within the joint economic lot size framework. We demonstrate that in this classical setting, partial integration can in fact be sufficient for eliminating informational inefficiency and achieving coordination. However, contrary to what one may expect, a tighter integration may harm supply chain performance and defeat coordination. We explain the underlying mechanism and investigate it analytically and numerically. Our results characterize sensitivity of supply chain performance to the degree of integration and stress the importance of the operational planning perspective for strategic decision making.
Endemism, invasion, and overseas dispersal: the phylogeographic history of the Lesser Antillean frog, Eleutherodactylus johnstonei
Authors: Yuan Michael L. , Frederick Jeffrey H. , McGuire Jimmy A. , Bell Rayna C. , Smith Struan R. , Fenton Calvin , Cassius Jourdan , Williams Rudell , Wang Ian J. , Powell Robert , Hedges S. Blair
Published: May 2022

Cryptogenic species are those whose native and introduced ranges are unknown. The extent and long history of human migration rendered numerous species cryptogenic. Incomplete knowledge regarding the origin and native habitat of a species poses problems for conservation management and may confound ecological and evolutionary studies. The Lesser Antilles pose a particular challenge with regard to cryptogenic species because these islands have been anthropogenically connected since before recorded history. Here, we use population genetic and phylogeographic tools in an attempt to determine the origin of Eleutherodactylus johnstonei, a frog species with a potentially widespread introduced range and whose native range within the Lesser Antilles is unknown. Based on elevated estimates of genetic diversity and within-island geographic structure not present elsewhere in the range, we identify Montserrat as the native island of E. johnstonei. We also document two major clades within E. johnstonei, only one of which is the primary source of introduced populations throughout the Americas. Our results demonstrate the utility of genetic tools for resolving cryptogenic species problems and highlight E. johnstonei as a potential system for understanding differences in invasive potential among sister lineages.
Predator suppression by a toxic invader does not cascade to prey due to predation by alternate predators
Authors: Teunissen Niki , Peters Anne
Published: May 2022

Invasive species often have catastrophic direct effects on native species through increased competition and predation. Less well understood are indirect, cascading effects across trophic levels. To reveal trophic disruptions caused by invasive species, it is necessary to document interactions between species at different trophic levels and across guilds. Here, we take this approach to quantify the impact of the invasion of cane toads at a riparian site in the Kimberley, northwest Australia. These toads are toxic to many native vertebrate predators and following toad arrival we observed the expected severe population decline in monitor lizards. Contrary to expectations however, this did not facilitate species in the next trophic level down: the abundance of their reptilian prey, as well as nest success of a songbird whose nests were predominantly depredated by monitor lizards, remained unchanged. Instead, detailed observations suggest a change in the suite of nest predators, with monitor lizards being replaced by other—mainly avian—predators, possibly reflecting their release from competitors that are more efficient nest predators. Hence, our findings highlight complex indirect effects of an invasive species across trophic levels and indicate that trophic cascades can go undetected when failing to include direct observations on predator–prey interactions.
Are All Directors Treated Equally? Evidence from Director Turnover Following Opportunistic Insider Selling
Authors: De Groote Sander , Bruynseels Liesbeth , Gaeremynck Ann
Published: May 2022

This study investigates the likelihood of director turnover following opportunistic insider selling. Given that opportunistic insider selling may be costly to a firm due to potential legal risk and firm legitimacy concerns, we hypothesize that directors engaging in this type of transactions have a higher likelihood of subsequently leaving the board. Using archival data of 11,409 directors in 2280 US firms from 2005 to 2014, univariate comparisons show that directors engaging in opportunistic insider selling are about 8% more likely to exit their firms’ board compared to directors not engaging in this behavior. Furthermore, multivariate results show that the likelihood of director departure following opportunistic insider selling is higher for some directors but not all. Specifically, directors who are especially valuable to the board or costly to replace do not seem to experience elevated levels of turnover. Interestingly, this difference in director turnover is only observed in smaller firms. We find that in larger firms, the likelihood of director turnover following opportunistic insider selling does not depend on director characteristics. As such, results seem to suggest that boards do not homogeneously self-regulate in this context as some directors seem to be shielded from turnover following unethical behavior.
FTO mediated ERBB2 demethylation promotes tumor progression in esophageal squamous cell carcinoma cells
Authors: Zhao Fangfang , Ge Fangfang , Xie Minghua , Li Zhenyu , Zang Chunbao , Kong Lingsuo , Pu Youguang , Zheng Xucai , Tan Yiao
Published: May 2022

N6-methyladenosine (m6A) is the most prevalent and internal modification that occurs in the messenger RNAs of eukaryotes. However, knowledge of the impact of these modifications on gene expression regulation remains limited. By using the in vitro MeRIP-seq and RNA-seq assays, we discovered that the mRNA demethylase FTO was significantly up-regulated in esophageal squamous cell carcinoma (ESCC) tissues and cells. Knockdown of FTO drastically suppressed the proliferation, migration, and invasion of ESCC cells. Furthermore, by using transcriptome-wide m6A-seq and RNA-seq assays, we identified ERBB2 is the target of FTO, which acts in concert in ESCC tumorigenesis and metastasis. Moreover, loss and gain functional studies suggested that the m6A reader YTHDF1 stabilizes ERBB2 mRNA via decoding the m6A modification. All these results uncovered a new signaling cascade, including FTO, YTHDF1, and ERBB2, which finely regulates the ESCC progression.
Do explicit review strategies improve code review performance? Towards understanding the role of cognitive load
Authors: Gonçalves Pavlína Wurzel , Fregnan Enrico , Baum Tobias , Schneider Kurt , Bacchelli Alberto
Published: May 2022

Code review is an important process in software engineering – yet, a very expensive one. Therefore, understanding code review and how to improve reviewers’ performance is paramount. In the study presented in this work, we test whether providing developers with explicit reviewing strategies improves their review effectiveness and efficiency. Moreover, we verify if review guidance lowers developers’ cognitive load. We employ an experimental design where professional developers have to perform three code review tasks. Participants are assigned to one of three treatments: ad hoc reviewing, checklist, and guided checklist. The guided checklist was developed to provide an explicit reviewing strategy to developers. While the checklist is a simple form of signaling (a method to reduce cognitive load), the guided checklist incorporates further methods to lower cognitive demands of the task such as segmenting and weeding. The majority of the participants are novice reviewers with low or no code review experience. Our results indicate that the guided checklist is a more effective aid for a simple review,while the checklist supports reviewers’ efficiency and effectiveness in a complex task. However, we did not identify a strong relationship between the guidance provided and code review performance. The checklist has the potential to lower developers’ cognitive load, but higher cognitive load led to better performance possibly due to the generally low effectiveness and efficiency of the study participants. Data and materials: 10.5281/zenodo.5653341. Registered report: 10.17605/OSF.IO/5FPTJ.
When Monitoring Facilitates Trust
Authors: Gordon Emma C.
Published: May 2022

It is often taken for granted that monitoring stands in some kind of tension with trusting (e.g., Hieronymi 2008; Wanderer and Townsend 2013; Nguyen forthcoming; McMyler 2011, Castelfranchi and Falcone 2000; Frey 1993; Dasgupta 1988, Litzky et al. 2006) — especially three-place trust (i.e., A trusts B to X), but sometimes also two-place trust (i.e., A trusts B, see, e.g., Baier 1986). Using a case study involving relationship breakdown, repair, and formation, I will argue there are some ways in which monitoring can be conducive to two-place trust, and to instances of three-place trust that are likely to be repeated over time—especially when previously established two-place trust has broken down. The result, I hope, is not any kind of abandoning of the important idea that monitoring can undermine trust, but an appreciation of where the conflict between monitoring and trustdoesn’tlie – one from which future work will hopefully be better positioned to illuminate where exactly the conflict is.