bluuebunny/crossref_metadata_2025 huggingface dataset:
South Africa and the Surgical Diaspora—A Hub for Surgical Migration and Training
Authors: Rudolfson Niclas , Lantz Adam , Shrime Mark G. , Johnson Walter , Smith Martin D. , Hagander Lars
Published: April 2023

Background

The shortage of trained surgeons, anesthesiologists, and obstetricians is a major contributor to the unmet need for surgical care in low‐ and middle‐income countries, and the shortage is aggravated by migration to higher‐income countries.

Methods

We performed a cross‐sectional observational study, combining individual‐level data of 43,621 physicians from the Health Professions Council of South Africa with data from the registers of 14 high‐income countries, and international statistics on surgical workforce, in order to quantify migration to and from South Africa in both absolute and relative terms.

Results

Of 6670 surgeons, anesthesiologists, and obstetricians in South Africa, a total of 713 (11%) were foreign medical graduates, and 396 (6%) were from a low‐ or middle‐income country. South Africa was an important destination primarily for physicians originating from low‐income countries; 2% of all surgeons, anesthesiologists, and obstetricians from low‐ and middle‐income countries were registered in South Africa, and 6% in the other 14 recipient countries. A total of 1295 (16%) South African surgeons, anesthesiologists, and obstetricians worked in any of the 14 studied high‐income countries.

Conclusion

South Africa is an important regional hub for surgical migration and training. A notable proportion of surgical specialists in South Africa were medical graduates from other low‐ or middle‐income countries, whereas migration out of South Africa to high‐income countries was even larger.
Comparison of the effects of long-lasting static stretching and hypertrophy training on maximal strength, muscle thickness and flexibility in the plantar flexors
Authors: Warneke Konstantin , Wirth Klaus , Keiner Michael , Lohmann Lars H. , Hillebrecht Martin , Brinkmann Anna , Wohlann Tim , Schiemann Stephan
Published: April 2023

Maximal strength measured via maximal voluntary contraction is known as a key factor in competitive sports performance as well as injury risk reduction and rehabilitation. Maximal strength and hypertrophy are commonly trained by performing resistance training programs. However, literature shows that long-term, long-lasting static stretching interventions can also produce significant improvements in maximal voluntary contraction. The aim of this study is to compare increases in maximal voluntary contraction, muscle thickness and flexibility after 6 weeks of stretch training and conventional hypertrophy training. Sixty-nine (69) active participants (f = 30, m = 39; age 27.4 ± 4.4 years, height 175.8 ± 2.1 cm, and weight 79.5 ± 5.9 kg) were divided into three groups: IG1 stretched the plantar flexors continuously for one hour per day, IG2 performed hypertrophy training for the plantar flexors (5 × 10–12 reps, three days per week), while CG did not undergo any intervention. Maximal voluntary contraction, muscle thickness, pennation angle and flexibility were the dependent variables. The results of a series of two-way ANOVAs show significant interaction effects (p < 0.05) for maximal voluntary contraction (ƞ2 = 0.143–0.32, p < 0.006), muscle thickness (ƞ2 = 0.11–0.14, p < 0.021), pennation angle (ƞ2 = 0.002–0.08, p = 0.077–0.625) and flexibility (ƞ2 = 0.089–0.21, p < 0.046) for both the stretch and hypertrophy training group without significant differences (p = 0.37–0.99, d = 0.03–0.4) between both intervention groups. Thus, it can be hypothesized that mechanical tension plays a crucial role in improving maximal voluntary contraction and muscle thickness irrespective whether long-lasting stretching or hypertrophy training is used. Results show that for the calf muscle, the use of long-lasting stretching interventions can be deemed an alternative to conventional resistance training if the aim is to increase maximal voluntary contraction, muscle thickness and flexibility. However, the practical application seems to be strongly limited as a weekly stretching duration of up to 7 h a week is opposed by 3 × 15 min of common resistance training.
Navigation and the efficiency of spatial coding: insights from closed-loop simulations
Authors: Ghazinouri Behnam , Nejad Mohammadreza Mohagheghi , Cheng Sen
Published: April 2023

Spatial learning is critical for survival and its underlying neuronal mechanisms have been studied extensively. These studies have revealed a wealth of information about the neural representations of space, such as place cells and boundary cells. While many studies have focused on how these representations emerge in the brain, their functional role in driving spatial learning and navigation has received much less attention. We extended an existing computational modeling tool-chain to study the functional role of spatial representations using closed-loop simulations of spatial learning. At the heart of the model agent was a spiking neural network that formed a ring attractor. This network received inputs from place and boundary cells and the location of the activity bump in this network was the output. This output determined the movement directions of the agent. We found that the navigation performance depended on the parameters of the place cell input, such as their number, the place field sizes, and peak firing rate, as well as, unsurprisingly, the size of the goal zone. The dependence on the place cell parameters could be accounted for by just a single variable, the overlap index, but this dependence was nonmonotonic. By contrast, performance scaled monotonically with the Fisher information of the place cell population. Our results therefore demonstrate that efficiently encoding spatial information is critical for navigation performance.
The Allen–Cahn equation with generic initial datum
Authors: Hairer Martin , Lê Khoa , Rosati Tommaso
Published: April 2023

We consider the Allen–Cahn equation $${\partial _t}{u}-\Delta u=u-u^3$$

∂
t

u
-
Δ
u
=
u
-

u
3

with a rapidly mixing Gaussian field as initial condition. We show that provided that the amplitude of the initial condition is not too large, the equation generates fronts described by nodal sets of the Bargmann–Fock Gaussian field, which then evolve according to mean curvature flow.
Coupled Thermo-hydro-mechanical Simulation of Hydraulic Fracturing in Deep Reservoirs Using Finite-Discrete Element Method
Authors: Sharafisafa Mansour , Aliabadian Zeinab , Sato Akira , Shen Luming
Published: April 2023

Hydraulic fracturing (HF) is one of the most effective stimulation techniques to enhance reservoir permeability. The efficiency of an HF fluid injection depends on the pre-existing discontinuities or sources of heterogeneities and these features need to be considered in a HF operation treatment. Moreover, deep reservoirs are usually located in hot dry rocks (HDR). Hence, thermal conduction through the rock and fluid and advection and convective heat transfer in the fluid can affect the fluid–rock interaction. This study focuses on HF development in deep reservoirs under a high-temperature field. Two separate scenarios are considered: a reservoir containing discrete fracture networks (DFN) and another considering blocks in a matrix as conglomerate reservoirs (there is no relation between the scenarios considered). The study discusses each reservoir separately and simulates their thermo-hydro-mechanical (THM) behaviour using the combined finite-discrete element method (FDEM). First, the capabilities of the FDEM are verified against the existing analytical solutions, and then the FDEM is employed to model HF development. The effects of controlling factors, including flow rate, fluid kinematic viscosity and DFN aperture for jointed reservoirs and flow rate, fluid kinematic viscosity and block strength in conglomerate ones, are studied. The results show that the high fracture density DFNs strongly affect the HF propagation pattern and fluid pressure rise. Moreover, the DFN’s aperture significantly alters the HF treatment behaviour. The controlling factors are observed to influence the HF pattern strongly, and a successful HF treatment requires careful consideration of all the factors. In the conglomerate reservoirs, the strength of the blocks strongly dominates the HF mechanism, in which soft blocks break and allow for uniform fluid pressure distribution and longer HFs, while hard blocks stop fluid from flowing over longer distances accumulating high fluid pressure around the injection. This mechanism excessively breaks the matrix and reduces HF efficiency. Crack branching frequently occurs in conglomerate reservoirs due to thermal exchange between the blocks, matrix, and fluid.
The impact of prior knowledge on causal structure learning
Authors: Constantinou Anthony C. , Guo Zhigao , Kitson Neville K.
Published: April 2023

Causal Bayesian networks have become a powerful technology for reasoning under uncertainty in areas that require transparency and explainability, by relying on causal assumptions that enable us to simulate hypothetical interventions. The graphical structure of such models can be estimated by structure learning algorithms, domain knowledge, or a combination of both. Various knowledge approaches have been proposed in the literature that enables us to specify prior knowledge that constrains or guides these algorithms. This paper introduces some novel, and also describes some existing, knowledge-based approaches that enable us to combine structure learning with knowledge obtained from heterogeneous sources. We investigate the impact of these approaches on structure learning across different algorithms, case studies and settings that we might encounter in practice. Each approach is assessed in terms of effectiveness and efficiency, including graphical accuracy, model fitting, complexity, and runtime; making this the first paper that provides a comparative evaluation of a wide range of knowledge approaches for structure learning. Because the value of knowledge depends on what data are available, we illustrate the results both with limited and big data. While the overall results show that knowledge becomes less important with big data due to higher learning accuracy rendering knowledge less important, some of the knowledge approaches are found to be more important with big data. Amongst the main conclusions is the observation that reduced search space obtained from knowledge does not always imply reduced computational complexity, perhaps because the relationships implied by the data and knowledge are in tension.
Perioperative TAS-118 plus oxaliplatin in patients with locally advanced gastric cancer: APOLLO-11 study
Authors: Takahari Daisuke , Katai Hitoshi , Takashima Atsuo , Izawa Naoki , Ishizuka Naoki , Ohashi Manabu , Mikami Shinya , Wakatsuki Takeru , Nakayama Izuma , Chin Keisho , Ida Satoshi , Kumagai Koshi , Nunobe Souya , Iwasa Satoru , Shoji Hirokazu , Wada Takeyuki , Doi Ayako , Yoshikawa Takaki , Sano Takeshi , Boku Narikazu , Yamaguchi Kensei
Published: April 2023

Background

We investigated the feasibility of perioperative chemotherapy with S-1 and leucovorin (TAS-118) plus oxaliplatin in patients with locally advanced gastric cancer.

Methods

Patients with clinical T3–4N1–3M0 gastric cancer received four courses of TAS-118 (40–60 mg/body, orally, twice daily for seven days) plus oxaliplatin (85 mg/m2, intravenously, day one) every two weeks preoperatively followed by gastrectomy with D2 lymphadenectomy, followed by postoperative chemotherapy with either 12 courses of TAS-118 monotherapy (Step 1) or eight courses of TAS-118 plus oxaliplatin (Step 2). The primary endpoints were completion rates of preoperative chemotherapy with TAS-118 plus oxaliplatin and postoperative chemotherapy with TAS-118 monotherapy (Step 1) or TAS-118 plus oxaliplatin (Step 2).

Results

Among 45 patients enrolled, the preoperative chemotherapy completion rate was 88.9% (90% CI 78.0–95.5). Major grade ≥ 3 adverse events (AEs) were diarrhoea (17.8%) and neutropenia (8.9%). The R0 resection rate was 95.6% (90% CI 86.7–99.2). Complete pathological response was achieved in 6 patients (13.3%). Dose-limiting toxicity was not observed in 31 patients receiving postoperative chemotherapy (Step 1, n = 11; Step 2, n = 20), and completion rates were 90.9% (95% CI 63.6–99.5) for Step 1 and 80.0% (95% CI 59.9–92.9) for Step 2. No more than 10% of grade ≥ 3 AEs were observed in  patients receiving Step 1. Hypokalaemia and neutropenia occurred in 3 and 2 patients, respectively, receiving Step 2. The 3-year recurrence-free and overall survival rates were 66.7% (95% CI 50.9–78.4) and 84.4% (95% CI 70.1–92.3), respectively.

Conclusions

Perioperative chemotherapy with TAS-118 plus oxaliplatin with D2 gastrectomy is feasible.
Analyzing and comparing the security of self-sovereign identity management systems through threat modeling
Authors: Grüner Andreas , Mühle Alexander , Lockenvitz Niko , Meinel Christoph
Published: April 2023

The concept of Self-Sovereign Identity (SSI) promises to strengthen the security and user-centricity of identity management. Since any secure online service relies on secure identity management, we comparatively analyze the intrinsic security of SSI. Thus, we adopt a hybrid threat modeling approach comprising STRIDE, attack trees, and ratings towards this unique context. Data flow diagrams of the isolated, centralized and the SSI model serve as the foundation for the assessment. The evolution of the paradigms shows an increasing complexity in security zones and communication paths between the components. We identified 35 threats to all SSI components and 15 protection measures that reduce the threats’ criticality. As a result, our research shows that the SSI paradigm’s threat surface is significantly higher compared to the traditional models. Besides the threat assessment on model level, the adapted methodology can evaluate a specific implementation. We analyzed uPort with a restricted scope to its user agent. Thus, 2 out of 10 threats were not properly addressed, leading to potential spoofing, denial, or repudiation of identity actions.
Derivative-free separable quadratic modeling and cubic regularization for unconstrained optimization
Authors: Custódio A. L. , Garmanjani R. , Raydan M.
Published: April 2023

We present a derivative-free separable quadratic modeling and cubic regularization technique for solving smooth unconstrained minimization problems. The derivative-free approach is mainly concerned with building a quadratic model that could be generated by numerical interpolation or using a minimum Frobenius norm approach, when the number of points available does not allow to build a complete quadratic model. This model plays a key role to generate an approximated gradient vector and Hessian matrix of the objective function at every iteration. We add a specialized cubic regularization strategy to minimize the quadratic model at each iteration, that makes use of separability. We discuss convergence results, including worst case complexity, of the proposed schemes to first-order stationary points. Some preliminary numerical results are presented to illustrate the robustness of the specialized separable cubic algorithm.
Free gs-Monoidal Categories and Free Markov Categories
Authors: Fritz Tobias , Liang Wendong
Published: April 2023

Categorical probability has recently seen significant advances through the formalism of Markov categories, within which several classical theorems have been proven in entirely abstract categorical terms. Closely related to Markov categories are gs-monoidal categories, also known as CD categories. These omit a condition that implements the normalization of probability. Extending work of Corradini and Gadducci, we construct free gs-monoidal and free Markov categories generated by a collection of morphisms of arbitrary arity and coarity. For free gs-monoidal categories, this comes in the form of an explicit combinatorial description of their morphisms as structured cospans of labeled hypergraphs. These can be thought of as a formalization of gs-monoidal string diagrams ($$=$$
=
term graphs) as a combinatorial data structure. We formulate the appropriate 2-categorical universal property based on ideas of Walters and prove that our categories satisfy it. We expect our free categories to be relevant for computer implementations and we also argue that they can be used as statistical causal models generalizing Bayesian networks.
Mites inhabiting nests of wood warbler, Phylloscopus sibilatrix (Aves: Passeriformes), in the Wielkopolska National Park in western Poland
Authors: Laska Alicja , Puchalska Ewa , Mikołajczyk Martyna , Gwiazdowicz Dariusz J. , Kaźmierski Andrzej , Niedbała Wojciech , Błoszyk Jerzy , Olszanowski Ziemowit , Szymkowiak Jakub , Hałas Natalia , Kuczyński Lechosław , Skoracka Anna
Published: April 2023

The wood warbler, Phylloscopus sibilatrix (Aves: Passeriformes), is a well-known model organism for studying bird migration, breeding habitat selection and nest predation. The nest acarofauna of this bird species has not been extensively studied so far. To provide a comprehensive report on mite species inhabiting wood warbler nests and to assess infestation parameters (prevalence, intensity, and abundance) for mite species and orders, we collected 45 nests of this bird species in the Wielkopolska National Park in western Poland. Analyses revealed a huge diversity (198 species) of mites inhabiting wood warbler nests. We found individuals belonging to the Mesostigmata, Trombidiformes and Sarcoptiformes. The Trombidiformes, represented in our study only by the Prostigmata, achieved statistically significantly lower intensity and abundance, compared to representatives of other orders. However, the number of recorded prostigmatid species was high (65). The most common were: Stigmaeus sphagneti (22 nests), Stigmaeus longipilis (16), Eupodes voxencollinus (15), Cunaxa setirostris (14), Stigmaeus pilatus (11), and Linopodes sp. 2 (10). The prevalence of Mesostigmata and Sarcoptiformes was equal, reaching 91.1%. Most of Gamasina (Mesostigmata) species found in this study were more characteristic of the soil environment and forest litter than bird nests, but there was also a typical bird parasite, viz. Ornithonyssus sylviarum. None of the observed species of Uropodina (Mesostigmata) or Oribatida (Sarcoptiformes) was typical for bird nests. Among the Uropodina, the highest parameters of nest infestation were achieved by Oodinychus ovalis, whereas among the Oribatida, they were achieved by Metabelba pulverosa. We discuss the importance of wood warbler nests for mite dispersal, survival and reproduction.
Association of baseline ROR1 and ROR2 gene expression with clinical outcomes in the I-SPY2 neoadjuvant breast cancer trial
Authors: Parker Barbara A. , Shatsky Rebecca A. , Schwab Richard B. , Wallace Anne M. ,   I-SPY 2 Consortium, Wolf Denise M. , Hirst Gillian L. , Brown-Swigart Lamorna , Esserman Laura J. , van ’t Veer Laura J. , Ghia Emanuela M. , Yau Christina , Kipps Thomas J.
Published: April 2023

Purpose

ROR1 and ROR2 are Type 1 tyrosine kinase-like orphan receptors for Wnt5a that are associated with breast cancer progression. Experimental agents targeting ROR1 and ROR2 are in clinical trials. This study evaluated whether expression levels of ROR1 or ROR2 correlated with one another or with clinical outcomes.

Methods

We interrogated the clinical significance of high-level gene expression of ROR1 and/or ROR2 in the annotated transcriptome dataset from 989 patients with high-risk early breast cancer enrolled in one of nine completed/graduated/experimental and control arms in the neoadjuvant I-SPY2 clinical trial (NCT01042379).

Results

High ROR1 or high ROR2 was associated with breast cancer subtypes. High ROR1 was more prevalent among hormone receptor-negative and human epidermal growth factor receptor 2-negative (HR-HER2-) tumors and high ROR2 was less prevalent in this subtype. Although not associated with pathologic complete response, high ROR1 or high ROR2 each was associated with event-free survival (EFS) in distinct subtypes. High ROR1 associated with a worse EFS in HR + HER2- patients with high post-treatment residual cancer burden (RCB-II/III) (HR 1.41, 95% CI = 1.11–1.80) but not in patients with minimal post-treatment disease (RCB-0/I) (HR 1.85, 95% CI = 0.74–4.61). High ROR2 associated with an increased risk of relapse in patients with HER2 + disease and RCB-0/I (HR 3.46, 95% CI = 1.33–9.020) but not RCB-II/III (HR 1.07, 95% CI = 0.69–1.64).

Conclusion

High ROR1 or high ROR2 distinctly identified subsets of breast cancer patients with adverse outcomes. Further studies are warranted to determine if high ROR1 or high ROR2 may identify high-risk populations for studies of targeted therapies.
Prenatal Exposure to Tobacco and Childhood Cognition and Behavior: Effect Modification by Maternal Folate Intake and Breastfeeding Duration
Authors: Hoyt Adrienne T. , Wilkinson Anna V. , Langlois Peter H. , Galeener Carol A. , Ranjit Nalini , Dabelea Dana M. , Moore Brianna F.
Published: April 2023

In this exploratory analysis, we assessed whether nutrition modified the association between prenatal exposure to tobacco and childhood cognition/behavior among 366 Colorado-based mothers and their offspring (born ≥ 37 weeks with birthweights ≥ 2500 g). Interaction by folate (</≥ 1074 µg/day) and breastfeeding (</≥ 5 months) was assessed by including a product term with cotinine (</≥ limit of detection [LOD]) in regression models for NIH Toolbox and Child Behavior Checklist T-scores. Main effects were observed between cotinine ≥ LOD and inhibitory control (− 3.2; 95% CI: − 6.8, 0.3), folate < 1074 µg/day and anxious/depressed symptoms (1.1; 95% CI: 0.1, 2.1), and breastfeeding < 5 months and receptive language (− 4.3; 95% CI: − 8.5, − 0.02), though these findings would not survive Bonferroni correction. Breastfeeding modified the tobacco-behavior associations. Sleep (3.8; 95% CI: 0.5, 7.1; interaction p-value = 0.02), depressive (4.6; 95% CI: 1.0, 8.2; interaction p-value = 0.01) and total problems (5.8; 95% CI: − 0.7, 12.4; interaction p-value = 0.09) were observed among tobacco-exposed offspring who breastfed > 5 months, but not for shorter durations. Our findings support the need for smoking cessation campaigns throughout pregnancy and throughout the postpartum period breastfeeding to reduce neurobehavioral risks in the offspring.
Toward agenda 2030 in education: policies and practices for effective school leadership
Authors: Ghamrawi Norma
Published: April 2023

School leadership has been described as a key target for leveraging the quality of education in relation to sustainable development goal (SDG4) that seeks to ‘ensure inclusive and quality education for all and promote lifelong learning’ as per UNESCO 2030 agenda. This study provides a policy review of school leadership in the State of Qatar, as a case study, but carries out discussions within the global thrive for meeting the demands of Agenda 2030 to achieve quality for public education. It utilized a research instrument developed by UNESCO’s Division for Policies and Lifelong Learning Systems in Paris. The study used personal interview surveying, also called face-to-face surveying, and was completed with high-level policymakers at the Ministry of Education and Higher Education (MOEHE). It consisted of four sections that addressed: (1) the regulatory frameworks governing school leadership; (2) the professional development opportunities offered to school leaders; (3) the degree the school leadership profession was attractive; and (4) the procedures followed to appraise school leaders. Findings underscore the critical role played by school autonomy, instructional leadership, and governance in responding to Agenda 2030. The discussion contributes to the global discourse in meeting the requirements of Agenda 2030.
It is about time: effects of thermal fluctuations resulting from climate change on trophic interactions with a focus on host–parasitoid interactions
Authors: Costaz Thibault P. M. , de Jong Peter W. , van Loon Joop J. A. , Dicke Marcel
Published: April 2023

Climate change alters many environmental parameters with strong consequences for ecological interactions, from species interactions to community dynamics. Temperature is crucial in determining ecosystem dynamics, especially for those involving ectothermic species such as plants or insects. Phenotypic plasticity, the capacity of one genotype to produce different phenotypes in response to environmental conditions, is a common mechanism by which individuals adapt to changing environments and is observed in multiple traits. The capacity of genotypes to adapt to novel temperature conditions plays a crucial role in structuring ecosystem dynamics and species persistence in adverse conditions. It is well recognised that temperature in natural ecosystems fluctuates over multiple time scales (e.g., hour, day, season, year). These fluctuations can follow predictable patterns or be unpredictable, with different consequences for phenotypic plasticity and ecosystem dynamics. Among trophic interactions, host–parasitoid interactions represent a special case because of the intimate symbiosis of the parasitoid larvae with their host. Understanding how and to what extent phenotypic plasticity structures species’ ecological niches is of utmost importance in the context of rapid climate change. With a particular focus on host–parasitoid interactions, this review discusses the literature on the role of phenotypic plasticity in fluctuating environments, highlighting the role of temporal dynamics. While we discuss literature on phenotypic plasticity at large, this review emphasises the fundamental effects of extreme temperatures in driving biochemical rates underlying phenotypic plasticity.
In vitro and in vivo assessment of the anti-inflammatory activity of olive leaf extract in rats
Authors: Fayez Nada , Khalil Waleed , Abdel-Sattar Essam , Abdel-Fattah Abdel-Fattah Mohamed
Published: April 2023

Inflammation is a complex and crucial process that protects the body against pathogens. Here in our study, we propose to scientifically justify the anti-inflammatory activity of olive leaf (OL). Initially, we ensured the safety of olive leaf extract (OLE) through acute oral administration of graded doses up to 4 g\kg in Wistar rats. Thus, the extract was considered generally safe. We also evaluated the ability of the extract to reduce carrageenan-induced rat paw edema. Compared to diclofenac sodium (10 mg/kg PO), OLE showed significant (P < 0.05) anti-inflammatory activity, showing the maximum inhibition percentage at the fifth hour of measurement at 42.31% and 46.99%, at doses of 200 and 400 m/kg, respectively, compared to 63.81% for the standard drug. To elucidate the potential mechanism, we measured TNF, IL-1, COX-2 and NO inside the paw tissue. Interestingly, OLE at all tested doses reduced the concentration of TNF and IL-1 to a level that was lower than that obtained by the standard drug. Additionally, OLE at the dose of 400 mg/kg reduced the levels of COX-2 and NO inside the paw tissue to a level that was statistically equivalent to the level observed in the normal control group. Finally, olive leaf extract at doses of 100, 200 and 400 mg/kg doses significantly (P < 0.05) inhibited the heat-induced hemolysis of RBCs membrane by 25.62, 57.40 and 73.88%, respectively, compared to 83.89% produced by aspirin. Consequently, we concluded that olive leaf extract has a significant anti-inflammatory activity through the reduction of TNF, IL-1, COX-2 and NO.
An injectable, self-healing and degradable hydrogel scaffold as a functional biocompatible material for tissue engineering applications
Authors: Li Shengyu , Mao Weiye , Xia Linying , Wu Xijin , Guo Yingxue , Wang Jingwei , Huang Jie , Xiang Hai , Jin Lu , Fu Huiying , Shou Qiyang
Published: April 2023

Injectable hydrogels derived from natural extracellular matrices exhibit excellent adhesion to endothelial cells in vitro and are ideal for many biomedical applications. However, their applicability in vivo is limited by the risk of infection or immunogenicity, and the current injectables also suffer from degradation, viscosity, and drug release. In this study, a multifunctional hydrogel scaffold (COB hydrogels) was constructed by incorporating bioactive glass nanoparticles with a Schiff base crosslinking-based hydrogel composed of carboxymethyl chitosan and oxidized cellulose. The incorporation of nanoparticles not only shortened the gelation time of the COB hydrogels, but also enhanced the performance of the hydrogel in terms of function, such as drug loading capacity. The prepared hydrogels also have self-healing ability, injectability, drug loading and sustained release, antibacterial properties and biocompatibility. In addition, given their no cytotoxicity and mild inflammation in vivo, the hydrogel scaffolds will be important for tissue engineering and drug delivery applications.
Implementation strategies preferred by primary care clinicians to facilitate cancer prevention and control activities
Authors: Glasgow Russell E. , Brtnikova Michaela , Dickinson L. Miriam , Carroll Jennifer K. , Studts Jamie L.
Published: April 2023

Key clinical and community members need to be involved in the identification of feasible and impactful implementation strategies for translation of evidence-based interventions into practice. While a wide range of implementation strategies has been developed, there is little research on their applicability for cancer prevention and control (CPC) efforts in primary care. We conducted a survey of primary care physicians to identify implementation strategies they perceive as most feasible and impactful. The survey included both primary prevention behavior change counseling and cancer screening issues. Analyses contrasted ratings of feasibility and impact of nine implementation strategies, and among clinicians in different settings with a focus on comparisons between clinicians in rural vs. non-rural settings. We recruited a convenience sample of 326 respondents from a wide range of practice types from four practice-based research networks in 49 states and including 177 clinicians in rural settings. Ratings of impact were somewhat higher than those for feasibility. Few of the nine implementation strategies were high on both impact and feasibility. Only ‘adapting to my practice’ was rated higher than a 4 (“moderate”) on both impact and feasibility. There were relatively few differences between rural and non-rural clinicians or associated with other clinician or setting characteristics. There is considerable variability in perceived impact and feasibility of implementation strategies for CPC activities among family medicine clinicians. It is important to assess both feasibility and impact of implementation strategies as well as their generalizability across settings. Our results suggest that optimal strategies to implement evidence-based CPC activities will likely need to be adapted for primary care settings. Future research is needed to replicate these findings and identify practical, implementation partner informed implementation strategies.
Rehydration Post-orientation: Investigating Field-Induced Structural Changes via Computational Rehydration
Authors: Brodmerkel Maxim N. , De Santis Emiliano , Caleman Carl , Marklund Erik G.
Published: April 2023

Proteins can be oriented in the gas phase using strong electric fields, which brings advantages for structure determination using X-ray free electron lasers. Both the vacuum conditions and the electric-field exposure risk damaging the protein structures. Here, we employ molecular dynamics simulations to rehydrate and relax vacuum and electric-field exposed proteins in aqueous solution, which simulates a refinement of structure models derived from oriented gas-phase proteins. We find that the impact of the strong electric fields on the protein structures is of minor importance after rehydration, compared to that of vacuum exposure and ionization in electrospraying. The structures did not fully relax back to their native structure in solution on the simulated timescales of 200 ns, but they recover several features, including native-like intra-protein contacts, which suggests that the structures remain in a state from which the fully native structure is accessible. Our findings imply that the electric fields used in native mass spectrometry are well below a destructive level, and suggest that structures inferred from X-ray diffraction from gas-phase proteins are relevant for solution and in vivo conditions, at least after in silico rehydration.
A Survey of Breastfeeding Attitudes and Health Locus of Control in the Nigerian Population
Authors: Adegbayi Adenike , Scally Andrew , Lesk Valerie , Stewart-Knox Barbara J
Published: April 2023

Objectives

Breastfeeding is important to infant health and survival in sub-Saharan Africa. To promote breastfeeding effectively, understanding of psychological factors associated with infant feeding choices is required. This study investigated breastfeeding attitudes and health locus of control (HLoC) in a Nigerian community sample.

Methods

Men and women (N = 400) (71% female; mean age 34.2 years/ range 18–86 years) were recruited through community groups in Nigeria. Self-report survey by questionnaire measured breastfeeding attitudes using the Iowa Infant Feeding Attitude Scale (IIFAS) and health locus of control using the Multidimensional Health Locus of Control Scale (MHLoCs).

Results Mean

IIFAS scores (mean = 57.7; sd = 7.8) became less favourable with increasing age (p = 0.02). Men had higher IIFAS scores (mean = 58.6; sd = 7.6) than women (mean = 56.6; sd = 8.0) indicating more favourable attitudes toward breastfeeding (p = 0.02). Women scored higher than men on external chance HLoC (ECHLoC) (p = 0.003) and external powerful others HLoC (EPHLoC) (p = 0.02). Increasing age was associated with higher scores on ECHLoC (p < 0.01) and EPHLoC (p < 0.01). Multiple linear regression analysis was significant (p < 0.001) and explained 7.8% of variance in breastfeeding attitude. Lower IIFAS scores, reflecting more negative attitudes to breastfeeding, were associated with higher ECHLoC (p < 0.01) and EPOHLoC (p < 0.05). Higher IIFAS scores, reflecting more positive attitudes to breastfeeding, were associated with greater IHLoC (p < 0.01). Neither age nor gender were associated with IIFAS scores in the final model.

Conclusions

This implies a need to explore health locus of control when promoting positive attitudes to breastfeeding and supporting families in breastfeeding advocacy.
Psychodynamic Psychotherapy for Postpartum Depression: A Systematic Review
Authors: Valverde N. , Mollejo E. , Legarra L. , Gómez-Gutiérrez M.
Published: April 2023

Objectives

Postpartum depression estimated prevalence in women is between 5 and 26% and it has adverse effects both on the mother, infant and her partner. Psychological treatments have proved to be effective for women with mild-to-moderate symptoms. Whereas several systematic reviews have assessed the effects of different psychological interventions for postpartum depression, such as cognitive-behavioural therapy or interpersonal therapy, no review assessing psychodynamic therapy has been carried out. A systematic review was conducted to evaluate the efficacy of psychodynamic therapy for postpartum depression.

Methods

Studies were identified using the following databases: PsycINFO, Psycarticles and Pubmed over January 2023. The requirements for the studies were the following: they had to be quantitative, available in English, including a psychodynamic intervention targeting treatment or prevention of postpartum depression which starts during pregnancy or within the first 12 months after giving birth. Case studies, qualitative studies or studies focused on improving parent-infant relationship or infant outcome were excluded from this research.

Results

Seven trials including 521 women met the inclusion criteria. In summary, three randomized controlled trials and four longitudinal studies were found. The most frequently used assessment tool was EPDS, five were individual interventions and the other two were group interventions.

Discussion

All studies reported the efficacy of psychodynamic interventions for postpartum depression, both in home and clinical settings and both in group and individual format. The limited number of trials, small sample sizes and lack of appropriate control groups were the main limitations.

Conclusions for practice

Psychodynamic therapy is probably efficient intervention for postpartum depression. Future research with strong methodological designs is needed to confirm these findings.

Significance

What is already known on this subject? Several systematic reviews have assessed the effects of different psychological interventions for postpartum depression, but no review assessing psychodynamic therapy has been carried out. What this study adds? A systematic review was conducted to evaluate the efficacy of psychodynamic therapy for postpartumdepression. This makes the systematic review a unique contribution to the literature.
Isolation and characterization of novel microsatellite loci for the Eastern Pacific marine sponge Mycale cecilia by Illumina MiSeq sequencing
Authors: Hernández-Lozano Misha Yazmín , Cruz-Barraza José Antonio , Rocha-Olivares Axayácatl
Published: April 2023

Background

Mycale cecilia is an abundant Eastern Tropical Pacific sponge living in a wide variety of habitats, including coral reefs where it may directly interact with corals. It is also known to possess secondary metabolites of pharmacological value. These aspects highlight the importance of having a better understanding of its biology, and genetic and population diversity.

Methods and results

In the present study, we isolated and characterized twelve novel microsatellite loci by Illumina MiSeq sequencing. The loci were tested in 30 specimens collected from two coral reef localities (La Paz, Baja California Sur and Isabel Island, Nayarit) from the Mexican Pacific using M13(-21) labeling. All loci were polymorphic, with two to nine alleles per locus. Expected heterozygosities varied from 0.616 to 0.901. Eleven loci were tested and successfully amplified in M. microsigmatosa from the Gulf of Mexico.

Conclusion

Here we report the first microsatellite loci developed for a sponge species from the Eastern Pacific coast. These molecular markers will be used for population genetic studies of M. cecilia, and potentially in other congeneric species; particularly in vulnerable marine areas that require protection, such as coral reefs.
The type IIS restriction enzyme MmeI can cut across a double-strand break
Authors: Tasnim Maliha , Selph T. Jacob , Olcott Jason , Hill Jonathon T.
Published: April 2023

Background

Type-IIS restriction enzymes cut outside their recognition sites, allowing them to remove their binding sites upon digestion. This feature has resulted in their wide application in molecular biology techniques, including seamless cloning methods, enzymatic CRISPR library generation, and others. We studied the ability of the Type-IIS restriction enzyme MmeI, which recognizes an asymmetric sequence TCCRAC and cuts 20 bp downstream, to cut across a double-strand break (DSB).

Methods and results

We used synthetic double-stranded oligos with MmeI recognition sites close to 5′ end and different overhang lengths to measure digestion after different periods of time and at different temperatures. We found that the MmeI binding and cutting sites can be situated on opposite sides of a DSB if the edges of the DNA molecules are held together by transient base-pairing interactions between compatible overhangs.

Conclusion

We found that MmeI can cut across a DSB, and the efficiency of the cutting depends on both overhang length and temperature.
Overloaded axial stress activates the Wnt/β-Catenin pathway in nucleus pulposus cells of adult degenerative scoliosis combined with intervertebral disc degeneration
Authors: Cai Zhijun , Luo Qibiao , Yang Xi , Pu Luqiao , Zong Haiyang , Shi Rongmao , He Pengju , Xu Yongqing , Li Yang , Zhang Jianping
Published: April 2023

Background

Intervertebral disc degeneration (IVDD) is the initiating factor of adult degenerative scoliosis (ADS), and ADS further accelerates IVDD, creating a vicious cycle. Nevertheless, the role of the Wnt/β-Catenin pathway in ADS combined with IVDD (ADS-IVDD) remains a mystery. Accordingly, this study was proposed to investigate the effect of axial stress on the Wnt/β-Catenin pathway in nucleus pulposus cells (NPCs) isolated from DS-IVDD patients.

Methods

Normal NPCs (N-NPC) were purchased and the NPCs of young (25–30 years; Y-NPC) and old (65–70 years; O-NPC) from ADS-IVDD patients were primary cultured. After treatment of NPC with overloaded axial pressure, CCK-8 and Annexin V-FITC kits were applied for detecting proliferation and apoptosis of N-NPC, Y-NPC and O-NPC, and western blotting was performed to assess the expression of Wnt 3a, β-Catenin, NPC markers and apoptosis markers (Bax, Bcl2 and Caspase 3).

Results

N-NPC, Y-NPC and O-NPC were mainly oval, polygonal and spindle-shaped with pseudopods, and the cell morphology tended to be flattened with age. N-NPC, Y-NPC and O-NPC were capable of synthesizing proteoglycans and expressing the NPC markers (Collagen II and Aggrecan). Notably, the expression of Wnt 3a, β-Catenin, Collagen II and Aggrecan was reduced in N-NPC, Y-NPC and O-NPC in that order. After overload axial stress treatment, cell viability of N-NPC and Y-NPC was significantly reduced, and the percentage of apoptosis and expression of Wnt 3a and β-Catenin were significantly increased.

Conclusions

Overloaded axial pressure activates the Wnt/β-Catenin pathway to suppress proliferation and facilitate apoptosis of NPC in ADS-IVDD patients.
Compact TE-pass polarizer based on silicon-on-insulator platform with bimetallic rhodium–silver grating
Authors: Hiza Ola Youssef M. , Younis B. M. , Areed Nihal F. F. , Hameed Mohamed Farhat O. , Obayya S. S. A.
Published: April 2023

An ultra-compact hybrid plasmonic grating based transverse electric (TE) pass polarizer using SOI platform is proposed and analyzed. The reported structure utilizes bi-metallic grating of noble metals; rhodium (Rh) and silver (Ag) as plasmonic materials to get benefit from their attractive properties. The rhodium is a corrosion-free, nonoxidizing, and chemically inert against aggressive chemicals noble metal. In conjunction with the use of Ag, Rh ensures better plasmonic response. The bi-metallic combination Ag/Rh exhibits large coupling between the quasi transverse magnetic mode confined in the silicon core and the surface plasmon mode constructed at the dielectric/metal interface, while the TE-mode can propagate with minimal losses. The modal characteristics of the proposed device are numerically investigated using full vectorial finite difference method, while the propagation analysis is performed using finite difference time domain method via Lumerical software package. The numerical results show that the TE-pass polarizer of a compact device length (LD) = 3.5 μm offers an extinction ratio (ER) of 36.6 dB and an insertion loss (IL) of about 0.8 dB at λ = 1.55 μm. Additionally, the reported polarizer is robust to fabrication errors keeping the ER larger than 20 dB and the IL less than 1 dB despite changing the geometrical parameters by $$\pm \hspace{0.17em}$$

±

10% in the wavelength range of 1.4 to 1.7 μm.
J–V characteristics of dark current in truncated conical quantum dot infrared photodetectors (QDIPs)
Authors: Ali Nouran M. , El-Batawy Yasser M.
Published: April 2023

Quantum Dot Infrared Photodetector (QDIP) is one of the promising candidates for infrared photodetection due to its controllable heterojunction bandgap and sensitivity to normal incident radiation. It is expected to be superior to infrared photodetectors of mature technologies such as Mercury Cadmium Telluride (HgCdTe) or a quantum well infrared photodetector. In the presented paper, we have developed a theoretical model for the dark current in truncated conical QDIP as the truncated conical shaped QD structure is more appropriate to describe the fabricated dots. The dark current model is based on the drift diffusion model solving the main governing Poisson’s and continuity equations. In this model, the carrier mobility is calculated by solving time-dependent Boltzmann transport equation in the photodetector material with embedded truncated conical QDs using finite difference technique. The results of the developed model have been compared with the dark current characteristics with published experimental results of Indium Arsenide/Gallium Arsenide (InAs/GaAs) truncated QDIP. The effects of QD volume, QD aspect ratio and QD density and the operating temperature on the dark current characteristics have also been investigated.
Clinical pharmacy services in critical care: results of an observational study comparing ward-based with remote pharmacy services
Authors: Hilgarth Heike , Wichmann Dominic , Baehr Michael , Kluge Stefan , Langebrake Claudia
Published: April 2023

Background

Pharmacists are essential team members in critical care and contribute to the safety of pharmacotherapy for this vulnerable group of patients, but little is known about remote pharmacy services in intensive care units (ICU).

Aim

We compared the acceptance of pharmacist interventions (PI) in ICU patients working remotely with ward-based service. We evaluated both pharmacy services, including further information on PI, including reasons, actions and impact.

Method

Over 5 months, a prospective single-centre observational study divided into two sequential phases (remote and ward-based) was performed on two ICU wards at a university hospital. After a structured medication review, PI identified were addressed to healthcare professionals. For documentation, the national database (ADKA-DokuPIK) was used. Acceptance was used as the primary endpoint. All data were analysed using descriptive methods.

Results

In total, 605 PI resulted from 1023 medication reviews. Acceptance was 75% (228/304) for remote and 88% (265/301; p < 0.001) for ward-based services. Non-inferiority was not demonstrated. Most commonly, drug- (44% and 36%) and dose-related (36% and 35%) reasons were documented. Frequently, drugs were stopped/paused (31% and 29%) and dosage changed (31% and 30%). PI were classified as “error, no harm” (National Coordinating Council for Medication Error Reporting and Prevention [NCC MERP] categories B to D; 83% and 81%). The severity and clinical relevance were at least ranked as "significant" (68% and 66%) and at least as "important" for patients (77% and 83%).

Conclusion

The way pharmacy services are provided influences the acceptance of PI. Remote pharmacy services may be seen as an addition, but acceptance rates in remote services failed to show non-inferiority.