bluuebunny/crossref_metadata_2025 huggingface dataset:
Polarimetric measurement of non-depolarizing optical systems
Authors: Ulloa-Peña Efrén , Muñoz-Flores Luis , Rodríguez-Herrera Oscar G. , Rosete-Aguilar Martha , Bruce Neil C.
Published: October 2023

The use of polarization measurements has become more common in recent years, as it gives more information than pure intensity measurements. Polarimetric components such as fixed or variable retarders and polarizers must be included in optical systems to obtain the polarization parameters required, and in many cases the optical system also includes other components such as relay and/or imaging optical systems. In this work we present a simple and robust method for the polarimetric characterization of non-depolarizing polarization components and other optical elements in the system, which does not require a full polarimeter. Since there is no depolarization, we represent the components as pure retarders with diattenuation and find their parameters (transmittance for the polarization components, angle of orientation of the fast axis, and retardance), from which we can retrieve their Mueller matrix. Our results show that the proposed method is accurate when compared with results obtained with a Mueller matrix dual-rotating retarder polarimeter calibrated using the eigenvalue calibration method, considered in this work as the gold standard, and is comparatively easier than the latter to implement, particularly for imaging polarimeters.
Least-squares method constrained by phase smoothness for correcting illumination fluctuation errors in phase-shifting profilometry
Authors: Zhu Huijie , Guo Hongwei
Published: October 2023

Phase-shifting fringe projection profilometry usually suffers from the errors induced by illumination fluctuations. As a result, ripple-like artifacts that have the same periods as fringes appear on the phase map. Because the illumination fluctuations cannot be simply modeled using fringe harmonics, their induced errors are difficult to remove by use of a phase-shifting algorithm. To solve this problem, this paper suggests a least-squares method constrained by phase smoothness. This method calculates fringe phases using the generalized phase-shifting algorithm and estimates coefficients related to illumination fluctuation by use of smoothed phase map. Alternately implementing these two steps enables one to eliminate effects of illumination fluctuations on the measurement results. Experimental results demonstrate that this proposed algorithm is helpful for improving measurement accuracy.
Fading suppression in the Ф-OTDR system based on a phase-modulated optical frequency comb
Authors: Zhang HongYing , Zhou JinZhe , Ma YunBin , Lei YanYang , Dong YongKang
Published: October 2023

In this paper, what we believe to be a novel method is proposed to suppress the fading effect of the phase-sensitive optical time domain reflectometer (Ф-OTDR) by using a phase-modulated optical frequency comb. In the Ф-OTDR system, intensity distributions of Rayleigh backscattering (RBS) light are different for pulsed probe lights with different central frequencies, therefore the locations of the fading points corresponding to signals of different frequencies are differently distributed, allowing the use of frequency division multiplexing to suppress the fading effects. In the experimental system of this paper, a continuous light in the form of a frequency comb is firstly generated through phase modulation. It is then modulated into a pulsed probe light and injected into the sensing fiber to produce different RBS intensity distributions. Finally, the extracted phase is processed by using the amplitude evaluation method, so that the distorted phase can be eliminated. Fading suppression is achieved using our system, and the effect of suppression is evaluated. By using an equal-amplitude optical frequency comb containing seven frequency components, the fading probability density of the system is dramatically reduced from the range of 5.49%-9.83% to 0.08%. Compared with the conventional system using a single acoustic-optic modulator to generate the frequency shift, the method proposed in this paper features a larger modulation bandwidth and more flexible frequency combination scheme to better suppress the fading effect. This method does not sacrifice the response bandwidth of the system, and the phase delay can be precisely controlled, which helps to fully suppress the fading effect.
Half-broadband two-dimensional electronic spectroscopy with active noise reduction
Authors: Bressan Giovanni , Heisler Ismael A. , Greetham Gregory M. , Edmeades Amy , Meech Stephen R.
Published: October 2023

Two-dimensional electronic spectroscopy (2DES) provides detailed insight into coherent ultrafast molecular dynamics in the condensed phase. Here we report a referenced broadband pump-compressed continuum probe half-broadband (HB) 2DES spectrometer in a partially collinear geometry. To optimize signal-to-noise ratio (SNR) we implement active noise reduction referencing, which has not previously been applied in 2DES. The method is calibrated against the well characterized 2DES response of the oxazine dye cresyl violet and demonstrated at visible wavelengths on the photochromic photoswitch 1,2-Bis(2-methyl-5-phenyl-3-thienyl) perfluorocyclopentene (DAE). The SNR is improved by a factor of ∼2 through active referencing. This is illustrated in an application to resolve a low frequency mode in the excited electronic state of DAE, yielding new data on the reaction coordinate. We show that the active noise reduction referencing, coupled with the rapid data collection, allows the extraction of weak vibronic features, most notably a low frequency mode in the excited electronic state of DAE.
Analysis and characterization of electro-optic coefficient for multi-layer polymers: dependence on measurement wavelengths
Authors: Enami Yasufumi , Yoshida Yuichi
Published: October 2023

We report a significant improvement in the measurement accuracy of electro-optic (EO) coefficients for low-loss EO polymers on substrates of sol-gel silica and indium tin oxide (ITO). Initially, we apply the standard Teng and Man reflection ellipsometric method, which results in substantial variability in the measured EO coefficients across a wavelength spectrum with changes as small as <1 nm. This variance leads to unreliable EO coefficient values ranging from a few to 70 pm/V at the 1.31 and 1.55 µm wavelengths. By adopting a transmission method for our experiments, we effectively mitigate the dependence of the measured EO coefficient on the wavelength variance of 0.2 nm. As a result, this new approach enables a more accurate and reliable measurement of the EO coefficients. This breakthrough presents a significant step forward in the field of EO research, paving the way for further exploration into the behavior and properties of EO polymers. Additionally, our findings highlight the importance of selecting an appropriate measurement method in accordance with the unique properties of the material under investigation.
Fabrication of 100-nm-period domain structure in lithium niobate on insulator
Authors: Ma Jianan , Cheng Xiaoyan , Zheng Ningchong , Chen Pengcheng , Xu Xiaoyi , Wang Tianxin , Wei Dunzhao , Nie Yuefeng , Zhu Shining , Xiao Min , Zhang Yong
Published: October 2023

Lithium niobate on insulator (LNOI) is a powerful platform for integrated photonic circuits. Recently, advanced applications in nonlinear and quantum optics require to controllably fabricate nano-resolution domain structures in LNOI. Here, we report on the fabrication of stable domain structures with sub-100 nm feature size through piezoelectric force microscopy (PFM) tip poling in a z-cut LNOI. In experiment, the domain dot with an initial diameter of 80 nm and the domain line with an initial width of 50 nm can survive after a storage of more than 3 months. Particularly, we demonstrate the successful fabrication of 1D stable domain array with a period down to 100 nm and a duty cycle of ∼50%. Our method paves the way to precisely manipulate frequency conversion and quantum entanglement on an LNOI chip.
Controlling the target pattern of projected LED arrays for smart lighting
Authors: Cerpentier Jeroen , Acuña Paula , Meuret Youri
Published: October 2023

High-resolution, pixelated LED arrays allow flexible illumination. By addressing certain areas of the LED matrix and projecting the emitted light, selective illumination can be achieved. When combined with computer vision, smart, autonomous lighting systems are within reach. However, limitations of the used projection optics, in combination with the fact that the LED array and camera can be at a different position, severely complicates the problem of calculating which LED pixels to address in order to achieve a desired target pattern. This work proposes a least-squares deconvolution-based calculation method to solve this problem. The method relies on an initial calibration step that characterizes the complete point-spread-function of the LED array for the considered illumination configuration. This allows using the system for various settings. The method is experimentally validated for an off-axis illumination configuration that demonstrates the accuracy and flexibility of the approach. Because the proposed algorithm is fast and guarantees a global optimum, it opens new avenues towards accurate, smart and adaptive illumination.
Two-dimensional phased array antenna beamforming system based on mode diversity
Authors: Wang Shiming , Li Xiuquan , Jia Yiliang , Hu Guijun
Published: October 2023

In this paper, a two-dimensional phased array antenna beamforming system based on mode diversity is demonstrated for the first time. The system uses few-mode long-period fiber gratings to excite different modes, and utilizes few-mode fiber Bragg gratings and 2 × 2 optical switches to control the propagation paths of optical signals, so as to realize the true time delay control of optical signals of different mode channels and complete the two-dimensional scanning of the beam. In order to prove the feasibility of the two-dimensional phased array antenna beamforming system based on mode diversity, we conduct experimental verification and performance testing of the system using optical switches to select the loop structures composed of the optical circulators. The far-field radiation patterns of 2 × 3 phased array antenna system of different frequencies are tested at different beam pointing angles. The experimental results are compared with the simulation results to demonstrate that the beam pointing angles have no squint. The beamforming system based on mode diversity takes modes as independent channels for the transmission of signals, and excites and processes signals of different modes in a single few-mode fiber core, which effectively reduces the volume and complexity of the optically controlled phased array radar system.
Genomes from historical Drosophila melanogaster specimens illuminate adaptive and demographic changes across more than 200 years of evolution
Authors: Shpak Max , Ghanavi Hamid R. , Lange Jeremy D. , Pool John E. , Stensmyr Marcus C.
Published: October 2023

The ability to perform genomic sequencing on long-dead organisms is opening new frontiers in evolutionary research. These opportunities are especially notable in the case of museum collections, from which countless documented specimens may now be suitable for genomic analysis—if data of sufficient quality can be obtained. Here, we report 25 newly sequenced genomes from museum specimens of the model organism Drosophila melanogaster, including the oldest extant specimens of this species. By comparing historical samples ranging from the early 1800s to 1933 against modern-day genomes, we document evolution across thousands of generations, including time periods that encompass the species’ initial occupation of northern Europe and an era of rapidly increasing human activity. We also find that the Lund, Sweden population underwent local genetic differentiation during the early 1800s to 1933 interval (potentially due to drift in a small population) but then became more similar to other European populations thereafter (potentially due to increased migration). Within each century-scale time period, our temporal sampling allows us to document compelling candidates for recent natural selection. In some cases, we gain insights regarding previously implicated selection candidates, such as ChKov1, for which our inferred timing of selection favors the hypothesis of antiviral resistance over insecticide resistance. Other candidates are novel, such as the circadian-related gene Ahcy, which yields a selection signal that rivals that of the DDT resistance gene Cyp6g1. These insights deepen our understanding of recent evolution in a model system, and highlight the potential of future museomic studies.
Reproducibility of biophysical in silico neuron states and spikes from event-based partial histories
Authors: Cudone Evan , Lower Amelia M. , McDougal Robert A.
Published: October 2023

Biophysically detailed simulations of neuronal activity often rely on solving large systems of differential equations; in some models, these systems have tens of thousands of states per cell. Numerically solving these equations is computationally intensive and requires making assumptions about the initial cell states. Additional realism from incorporating more biological detail is achieved at the cost of increasingly more states, more computational resources, and more modeling assumptions. We show that for both a point and morphologically-detailed cell model, the presence and timing of future action potentials is probabilistically well-characterized by the relative timings of a moderate number of recent events alone. Knowledge of initial conditions or full synaptic input history is not required. While model time constants, etc. impact the specifics, we demonstrate that for both individual spikes and sustained cellular activity, the uncertainty in spike response decreases as the number of known input events increases, to the point of approximate determinism. Further, we show cellular model states are reconstructable from ongoing synaptic events, despite unknown initial conditions. We propose that a strictly event-based modeling framework is capable of representing the complexity of cellular dynamics of the differential-equations models with significantly less per-cell state variables, thus offering a pathway toward utilizing modern data-driven modeling to scale up to larger network models while preserving individual cellular biophysics.
Introduction to the programme guidance for the use of iodised salt in processed foods and its pilot implementation, strengthening strategies to improve iodine status
Authors: Knowles Jacky , Codling Karen , Houston Robin , Gorstein Jonathan
Published: October 2023

Efforts to achieve optimal iodine intake through salt iodisation have focussed primarily on iodisation of household salt. However, there is strong evidence that in most regions of the world, industrially processed foods and condiments are an increasingly important source of dietary salt. In this context The Iodine Global Network (IGN) and partners developed programme guidance to help national programme managers assess the potential contribution of widely consumed industrially processed foods and condiments to iodine intake. The programme guidance additionally aimed to facilitate better understanding of iodised salt use by the processed food industry, review existing salt iodisation legislation for inclusion of food industry salt, and investigate how regulatory monitoring of food industry practices could be strengthened if needed. To evaluate the utility of the guidance in practice and identify areas where it could be improved, the IGN requested expressions of interest to pilot test implementation. Five pilots were implemented in Kenya, North Macedonia, The Republic of Moldova, Sri Lanka and Thailand, with remote technical support from IGN. The pilots demonstrated how evidence from implementation could be used to strengthen existing salt iodisation initiatives. In particular, how modelling existing processed food intake data enhanced understanding of potential or actual iodised salt intake and provided an evidence base for strategic change, as well as encouraging alignment with salt reduction programmes. In summary, the guidance provided a useful framework for national teams to conduct a relatively rapid assessment of the existing programme for achieving optimal iodine nutrition and opportunities to strengthen it. National teams involved with the pilot implementation were highly engaged and motivated by the outcomes. The pilot implementation process resulted in the development of strategic recommendations nationally and provided invaluable feedback to IGN on the utility of the guidance, facilitating development of an improved version.
Women and health providers’ perspectives on male support for cervical cancer screening in Gwanda district, Zimbabwe
Authors: Mantula Fennie , Toefy Yoesrie
Published: October 2023

Several studies have shown that male involvement increases the uptake of sexual and reproductive health programmes for improved family health outcomes. The role of men in reducing the burden of cervical cancer has however not been researched in Zimbabwe. It is for this reason that this study explores male support for cervical cancer screening programmes from the perspective of women and health providers in the Gwanda district of Zimbabwe. A qualitative approach that engaged thirty-six women aged 25–50 years in focus group discussions, and twenty-five health providers with different roles in the cervical cancer screening programme in in-depth interviews was used to determine their perspectives on male support for cervical cancer screening. Data were analysed thematically using ATLAS.ti Computer Assisted Qualitative data analysis software. Key findings reflected that men lacked knowledge on cervical cancer and its risk factors and prevention. Subsequently, they engaged in sexual behaviours that increased their partners’ risk of acquiring Human Papillomavirus infection, the virtually necessary cause of cervical cancer. Furthermore, men did not provide the necessary emotional and financial support for their women to access screening and treatment. Participants were optimistic that innovative awareness creation strategies and intense, sustained cervical cancer education efforts targeting men could increase male partner support. Involvement of community leaders was seen as crucial in the facilitation of male involvement for programme acceptance and improved uptake of cervical cancer screening. Male involvement is seen as an integral component of the cervical cancer prevention and control programme that has to be implemented in Gwanda district to minimise male partner-related barriers to cervical cancer screening. Further research focusing on men is required to identify specific knowledge gaps that would enable development of appropriate strategies that best involve men in cervical cancer prevention and control interventions.
Effectiveness of nirmatrelvir-ritonavir for the treatment of patients with mild to moderate COVID-19 and at high risk of hospitalization: Systematic review and meta-analyses of observational studies
Authors: Souza Kathiaja Miranda , Carrasco Gabriela , Rojas-Cortés Robin , Michel Barbosa Mariana , Bambirra Eduardo Henrique Ferreira , Castro José Luis , Alvares-Teodoro Juliana
Published: October 2023

Objective

To assess the effectiveness of nirmatrelvir-ritonavir in the treatment of outpatients with mild to moderate COVID-19 who are at higher risk of developing severe illness, through a systematic review with meta-analyses of observational studies.

Methods

A systematic search was performed, in accordance with the Cochrane search methods, to identify observational studies that met the inclusion criteria. The outcomes of mortality and hospitalization were analyzed. Search was conducted on PubMed, EMBASE, and The Cochrane Library. Two reviewers independently screened references, selected the studies, extracted the data, assessed the risk of bias using ROBINS-I tool and evaluated the quality of evidence using the GRADE tool. This study followed the PRISMA reporting guideline.

Results

A total of 16 observational studies were finally included. The results of the meta-analysis showed that in comparison to standard treatment without antivirals, nirmatrelvir-ritonavir reduced the risk of death by 59% (OR = 0.41; 95% CI: 0.35–0.52; moderate certainty of evidence). In addition, a 53% reduction in the risk of hospital admission was observed (OR = 0.47; 95% CI: 0.36–0.60, with very low certainty of evidence). For the composite outcome of hospitalization and/or mortality, there was a 56% risk reduction (OR = 0.44; 95% CI: 0.31–0.64, moderate certainty of evidence).

Conclusion

The results suggest that nirmatrelvir-ritonavir could be effective in reducing mortality and hospitalization. The results were valid in vaccinated or unvaccinated high-risk individuals with COVID-19. Data from ongoing and future trials may further advance our understanding of the effectiveness and safety of nirmatrelvir-ritonavir and help improve treatment guidelines for COVID-19.
Generalized external synchronization of networks based on clustered pandemic systems—The approach of Covid-19 towards influenza
Authors: Marwan Muhammad , Han Maoan , Khan Rizwan
Published: October 2023

Real-world models, like those used in social studies, epidemiology, energy transport, engineering, and finance, are often called “multi-layer networks.” In this work, we have described a controller that connects the paths of synchronized models that are grouped together in clusters. We did this using Lyapunov theory and a variety of coupled matrices to look into the link between the groups of chaotic systems based on influenza and covid-19. Our work also includes the use of external synchrony in biological systems. For example, we have explained in detail how the pandemic disease covid-19 will get weaker over time and become more like influenza. The analytical way to get these answers is to prove a theorem, and the numerical way is to use MATLAB to run numerical simulations.
Cross-cultural translation and psychometric validation of the French version of the Fear-Avoidance Components Scale (FACS)
Authors: Duport Arnaud , Bédard Sonia , Raynauld Catherine , Bordeleau Martine , Neblett Randy , Balg Frédéric , Devanne Hervé , Léonard Guillaume
Published: October 2023

Background

The Fear-Avoidance Components Scale (FACS) is a reliable and valid instrument widely used to assess fear-avoidance beliefs related to pain and disability. However, there is a scarcity of validated translations of the FACS in different cultural and linguistic contexts, including the French population. This study aimed to translate and validate the French version of the FACS (FACS-Fr/CF), examining its psychometric properties among French-speaking individuals.

Methods

A cross-cultural translation process–including forward translation, backward translation, expert committee review, and pre-testing–was conducted to develop the FACS-Fr/CF. The translated version was administered to a sample of French-speaking adults (n = 55) with chronic musculoskeletal pain. Internal consistency (including confirmatory analyses of the 2 factors identified in the Serbian version), test-retest reliability and convergent validity were then assessed.

Results

The FACS-Fr/CF demonstrated high global internal consistency (α = 0.94, 95% CI: 0.91–0.96) as well as high internal consistency of the 2 factors identified in the Serbian version (α = 0.90, 95% CI: 0.86–0.94 and α = 0.90, 95% CI: 0.85–0.94, respectively). Test-retest analysis revealed a moderate (close to high) reliability (ICC = 0.89; 95% CI: 0.82–0.94 and r = 0.89; p<0.005). Convergent validity was supported by significant correlations between the FACS-Fr/CF scores and the Tampa Scale for Kinesiophobia (r = 0.82; p < 0.005), the Pain Catastrophizing Scale (r = 0.72; p < 0.005) and the Hospital Anxiety and Depression Scale (r = 0.66; p < 0.005).

Conclusion

The present study provides evidence for the cross-cultural translation and psychometric validation of the FACS-Fr/CF. The FACS-Fr/CF exhibits a high internal consistency, a moderate (close to high) test-retest reliability, and good construct validity, suggesting its utility in assessing fear-avoidance beliefs in the French-speaking population. This validated tool can enhance the assessment and understanding of fear-avoidance behaviors and facilitate cross-cultural research in pain-related studies.
Locking solutions for prevention of central venous access device complications in the adult critical care population: A systematic review
Authors: Ornowska Marlena , Smithman Joshua , Reynolds Steven
Published: October 2023

Background

The objective of this systematic review is to determine the extent and quality of evidence for use of different types of locking fluids to prevent central venous access device complications in adult critical care patients. Specifically, rates of catheter-related bloodstream infection, colonization, and occlusion were considered. All types of devices were included in the review: central venous catheters, peripherally- inserted central catheters and hemodialysis catheters.

Methods

Eligibility criteria. Papers had to include adult (>18 years old) critical care patients, be experimental trials, conducted in North America and Europe, and published in peer-reviewed journals from 2010 onwards.

Information sources. A search of Medline and EMBASE databases was performed. The search is current as of November 28th, 2022.

Risk of bias. The Cochrane Risk of Bias 2 and the Risk of Bias In Non-Randomized Studies of Intervention tools were used to assess the risk of bias in included studies.

Results

Included studies. A total of 240 paper titles and abstracts underwent review, of these seven studies met the final criteria for quality appraisal. A total of three studies earned a low risk of bias quality appraisal.

Discussion

Limitations of evidence. Due to heterogeneity of types of locking fluids investigated and small number of studies identified, meta-analysis of results was not possible.

Interpretation. Out of all fluids investigated, only citrate 46.7% was found to statistically reduce central venous access device complication rates. This systematic review has also identified a gap in the literature regarding studies of locking fluids that are adequately powered in this patient population.

Future directions

Future research should include investigations and use of novel locking fluids with more effective properties against complications. It is imperative that future studies are adequately powered, randomized controlled trials in this patient population to facilitate optimal evidence-based care.
Prevalence of hypertension in adults living at altitude in Latin America and the Caribbean: A systematic review and meta-analysis
Authors: Zila-Velasque J. Pierre , Soriano-Moreno David R. , Medina-Ramirez Sebastian A. , Ccami-Bernal Fabricio , Castro-Diaz Sharong D. , Cortez-Soto Andrea G. , Esparza Varas Analis L. , Fernandez-Morales Jared , Olortegui-Rodriguez Juan J. , Pelayo-Luis Isabel P. , Zafra-Tanaka Jessica Hanae
Published: October 2023

Objective

The objective of this systematic review and meta-analysis was to assess the prevalence of hypertension in populations living at altitude in Latin America and the Caribbean.

Methods

We conducted a systematic search from January 1, 2000 to January 10, 2023 in Web of Science (WoS)/Core Collection, WoS/Medline, WoS/Scielo, Scopus, PubMed and Embase databases. We included studies that assessed the prevalence of hypertension in altitude populations (>1500 m.a.s.l.) and these were meta-analyzed using a random-effects model. To assess the sources of heterogeneity, we performed subgroup and meta-regression analyses.

Results

Thirty cross-sectional studies (117 406 participants) met the inclusion criteria. Studies used different cut-off points. The prevalence of hypertension in the studies that considered the cut-off point of ≥ 140/90 mmHg in the general population was 19.1%, ≥ 130/85 mmHg was 13.1%, and ≥ 130/80 mmHg was 43.4%. There was a tendency for the prevalence of hypertension to be higher in men. In meta-regression analyses, no association was found between altitude, mean age, year of publication, risk of bias and prevalence of hypertension.

Conclusion

The prevalence of hypertension in the altitude population of Latin America and the Caribbean is lower than that reported in populations living at sea level and lower than other altitude populations such as Tibetans.

PROSPERO

CRD42021275229.
A study of the effect of population aggregation on common prosperity: Evidence from 283 Chinese cities
Authors: Chen Jia , Ping Ying , Jia Jiefei , Li Guangliang
Published: October 2023

More than 40 years of urbanization in China has brought rapid economic growth, but the uneven development of region and how to achieve common prosperity through urbanization remain a serious concern. This paper analyzes the effect of the urbanization mode of population aggregation in central cities on common prosperity in China. Using panel data of 283 cities from 2004 to 2019, the study constructs a common prosperity index based on the coupling coordination degree of economy, ecology, and society. The Spatial Durbin Model is used to analyze the influence of population aggregation in central cities on common prosperity and the moderating effect of financial self-sufficiency rate. The results show that population aggregation in central cities has a positive effect on common prosperity. There is also a spatial spillover effect, but the impact exhibits an inverted U-shaped characteristic. Moreover, the fiscal self-sufficiency rate has a negative moderating impact on the effect of population aggregation on common prosperity in the early stage, but a positive moderating impact in the later period. This paper concludes by suggesting that the government should promote urbanization, control the size of large cities, accelerate the reform of household registration, and pay attention to the coordinated development of economy, society, and ecology to promote the realization of common prosperity.
Association between malaria and undernutrition among pregnant women at presentation for antenatal care in health facilities in the Mount Cameroon region
Authors: Jugha Vanessa Tita , Anchang Juliana Adjem , Taiwe Germain Sotoing , Kimbi Helen Kuokuo , Anchang-Kimbi Judith Kuoh
Published: October 2023

In resource limited settings, malaria and undernutrition are major public health problems in pregnancy. Therefore, this study assessed the association between malaria infection and undernutrition among pregnant women in the Mount Cameroon area. This cross-sectional study enrolled 1,014 pregnant women consecutively over a year. A structured questionnaire was used to collect socio-demographic information and clinical data. Maternal nutrition was assessed using dietary diversity (DD). Peripheral blood samples collected were used for the diagnosis of malaria parasitaemia by microscopy whereas haemoglobin (Hb) levels were determined using an Hb meter. Logistic regression was used to determine factors associated with malaria and dietary diversity. The prevalence of malaria infection and undernutrition was 17.8% and 89.6% respectively. In addition, of those infected with malaria, geometric mean parasite density was 301/μL of blood (range: 40–9280) while mean DD score was 3.57±0.82 (range: 1–7). The odds of being infected with malaria parasitaemia was highest among women enrolled in the rainy season (OR = 1.58, P = 0.043), who were farmers (OR = 2.3, P = 0.030), had a household size of < 4 individuals (OR = 1.48, P = 0.026) and who were febrile (OR = 1.87, P < 0.001). Also, attending clinic visits in Mutengene Medical Centre (OR = 2.0, P = 0.012) or Buea Integrated Health Centre (OR = 2.9, P = < 0.001), being < 25 years (OR = 2.4, P = 0.002) and a farmer (OR = 10.6, P = 0.024) as well as < 4 clinic visits (OR = 1.62, P = 0.039) were identified as predictors of undernutrition. Furthermore, the association between malaria and DD was statistically significant (P = 0.015). In this study, undernutrition was highly frequent than malaria infection. Thus, there is an urgent need to improve maternal awareness through nutritional counselling and health campaigns on the benefits of consuming at least five food groups. Besides, improved maternal dietary nutrient intake is likely to have impact on the burden of malaria parasite infection.
The usefulness of a complete blood count in the prediction of the first episode of schizophrenia diagnosis and its relationship with oxidative stress
Authors: Juchnowicz Dariusz , Dzikowski Michał , Rog Joanna , Waszkiewicz Napoleon , Karakuła Kaja Hanna , Zalewska Anna , Maciejczyk Mateusz , Karakula-Juchnowicz Hanna
Published: October 2023

A complete blood count (CBC) is a routinely performed blood examination. Only a few studies assess the relationship between CBC and oxidative stress (OS) in schizophrenia (SZ). The aim of the study was to assess the utility of CBC in the prediction of SZ diagnosis, and the relationship between CBC and OS. The study included: 47 individuals with the first episode of psychosis (26 drug-naive: FEP-nt; 21 patients under antipsychotic treatment: FEP-t) and 30 healthy persons (control group, HC). CBC and oxidative stress-related parameters were assessed in blood samples. The FEP group had higher levels of WBC, MCHC, NEU, MONO, EOZ, BASO, and %EOZ compared to HC (p<0.05). Various relationships between OS and CBC were found, and this connection was significantly different between healthy individuals and patients. The most promising C&RT model for discriminating FEP from HC was combining monocytes, eosinophils, and neutrophils (accuracy: 77%, 95%CI = 0.67–0.87). The analysis singled out WBC and HT (accuracy: 74%, 95%CI = 0.64–0.90) as the most promising to distinguish FEP-nt from HC; WBC and %Neu to allocate to FEP-t or HC group (accuracy: 87%, 95%CI = 0.64–0.90); RDW-SD and LYMPH (accuracy: 86%, 95% CI = 0.75–97) for distinguishing FEP-nt from FEP-t. CBC could be a promising, cheap tool to determine abnormalities related to schizophrenia. However, more studies with larger sample sizes are required.
Effect of pharmacist-led intervention protocol on preventing postoperative delirium after elective cardiovascular surgery
Authors: Asai Yuki , Yanagawa Tatsuki , Takahashi Masaaki
Published: October 2023

Postoperative delirium (PD) is an acute brain dysfunction, with a particularly high incidence after cardiovascular surgery. Pharmacist-led interventions show limited evidence in attenuating PD in cardiovascular surgery. In this retrospective cohort study, we aimed to clarify the risk factors of PD for cardiovascular surgery focused on pharmacotherapy and elucidate the effect of pharmacist-led intervention on the PD attenuation rate based on protocol-based pharmaceutical management (PBPM). This study included 142 adult patients who underwent elective valve replacement or valvuloplasty. The risk factors for PD were investigated using multivariate logistic regression analysis. Taking risk factors into consideration, a protocol was developed to discontinue benzodiazepines prescriptions by ward pharmacists, and replace with ramelteon and suvorexant if all the following factors apply: 1) number of medications ≥ 6 drugs, 2) number of doses to take ≥ 4 times, and 3) regular use of benzodiazepines or insomnia. Subsequently, the PD rate was compared during a period of two years and 6 months between the pre-PBPM (n = 39) and post-PBPM (n = 62). The PD rate for elective valve replacement or valvuloplasty was 25% (35/142). The adjusted odds ratio for polypharmacy was 3.3 (95% confidence interval: 1.2–8.9, p = 0.016), suggesting that preoperative risk assessment may be essential for patients with polypharmacy. The PD rate significantly decreased to 13% (8/62) in the post-PBPM group compared with 33% (13/39) in the pre-PBPM group (p = 0.014). There was a significant decrease in benzodiazepines use in post-PBPM compared with pre-PBPM (p = 0.026); however, the rate of ramelteon and orexin receptor antagonists use increased by PBPM introduction (p < 0.001). Although the present PBPM still requires further modification, it is simple and potentially useful for pharmacists to assess the risk of patients undergoing any elective cardiovascular surgery.
Experiences of university teachers with rotational blended learning during the COVID-19 pandemic: A qualitative case study
Authors: Alkaabi Ahmed , Qablan Ahmad , Alkatheeri Fatima , Alnaqbi Aisha , Alawlaki Maha , Alameri Latifa , Malhem Bushra
Published: October 2023

This qualitative case study examines the self-efficacy of university teachers during the COVID-19 pandemic as they struggle to incorporate new technology, teaching strategies, and curriculum delivery in the shift from total remote learning to biweekly rotation learning––two weeks of face-to-face learning and two weeks online. This study was conducted over one full semester among university teachers teaching undergraduate students with the rotation model at one federal university located in the United Arab Emirates. A case study design was used as a methodology to guide this research with a primary data collection method of semi-structured interviews of 11 teachers corroborated by both in-person and online classroom observations. Participating teachers were from various colleges within the university, including medicine, education, business, law, humanities, and science. The data from the interviews and observations were analyzed using thematic analysis, which yielded the following six themes: (1) continuously changing expectations, (2) mixed feelings regarding technology self-efficacy, (3) loss of learning among undergraduate students, (4) trial and error with teaching strategies, (5) the need to consult with students in the teaching and learning process, and (6) the shift from struggle to resilience. The results of the study indicated that having clearer expectations, proper technology training, and intradepartmental collaboration may help educators overcome the challenges associated with the hybrid rotation model. These results are expounded thoroughly along with relevant implications for robust leadership practices to enhance the quality of teaching and learning during potential future crises.
Measurement properties of cervical joint position error in people with and without chronic neck pain
Authors: AlDahas Ahmad , Devecchi Valter , Deane Janet A. , Falla Deborah
Published: October 2023

Background

People with chronic neck pain (CNP) often present with impaired neck proprioception. The most widely used clinical test for assessing neck proprioception is cervical joint position sense which measures joint position error (JPE). This clinical test is typically performed using a laser pointer to examine the accuracy of returning to a neutral head position (NHP) or target head position (THP) following active neck movements. The aim of this study was to determine the measurement properties of JPE using a laser pointer when tested in people with and without CNP under a variety of different testing conditions (i.e., different movement directions, sitting versus standing, NHP versus THP).

Methods

Forty-three participants (23 asymptomatic and 20 with CNP) underwent neck proprioception testing, returning to a NHP and THP in both sitting and standing positions (six trials for each test). A laser pointer was secured on the participant’s forehead and inertial measurement unit (IMU) sensors were placed beneath the laser pointer and at the level of the spinous process of the seventh cervical vertebra. Both the absolute and the constant JPE were assessed.

Findings

For the asymptomatic participants, good reliability (ICC: 0.79) was found only for right rotation of the THP task in sitting. In standing, good reliability (ICC: 0.77) was only found in flexion for the THP task. In standing, good reliability (ICC: 0.77) was only found for right rotation of the THP for the absolute JPE and left rotation (ICC: 0.85) for the constant error of the NHP task. In those with CNP, when tested in sitting, good reliability was found for flexion (ICC: 0.8) for the absolute JPE and good reliability (ICC range: 0.8–0.84) was found for flexion, extension, and right rotation for the constant JPE. In standing, good reliability (ICC range: 0.81–0.88) was found for flexion, and rotation for the absolute JPE. The constant JPE showed good reliability (ICC: 0.85) for right rotation and excellent reliability (ICC: 0.93) for flexion. Validity was weak to strong (r range: 0.26–0.83) and moderate to very strong (r range: 0.47–0.93) for absolute and constant error respectively, when tested in sitting. In standing, the validity was weak to very strong (0.38–0.96) for the absolute JPE and moderate to very strong (r range: 0.54–0.92) for the constant JPE.

Conclusion

The reliability of the measure of JPE when tested in sitting and standing in both groups showed good reliability, but not for all movements. The results of the current study also showed that the laser pointer correlated well with the Noraxon IMUs, but not for all movements. The results of the current study support the use of the JPE using a laser pointer in clinical and research settings.
Evaluation of stretch reflex synergies in the upper limb using principal component analysis (PCA)
Authors: Torell Frida
Published: October 2023

The dynamic nature of movement and muscle activation emphasizes the importance of a sound experimental design. To ensure that an experiment determines what we intend, the design must be carefully evaluated. Before analyzing data, it is imperative to limit the number of outliers, biases, and skewness. In the present study, a simple center-out experiment was performed by 16 healthy volunteers. The experiment included three load conditions, two preparatory delays, two perturbations, and four targets placed along a diagonal path on a 2D plane. While the participants performed the tasks, the activity of seven arm muscles were monitored using surface electromyography (EMG). Principal component analysis (PCA) was used to evaluate the study design, identify muscle synergies, and assess the effects of individual quirks. With PCA, we can identify the trials that trigger stretch reflexes and pinpoint muscle synergies. The posterior deltoid, triceps long head, and brachioradialis were engaged when targets were in the direction of muscle shortening and the perturbation was applied in the opposite direction. Similarly, the pectoralis and anterior deltoid were engaged when the targets were in the direction of muscle shortening and the perturbation was applied in the opposite direction. The stretch reflexes were not triggered when the perturbation brought the hand in the direction of, or into the target, except if the muscle was pre-loaded. The use of PCA was also proven valuable when evaluating participant performance. While individual quirks are to be expected, failure to perform trials as expected can adversely affect the study results.
The relationship between hemoglobin and V˙O2max: A systematic review and meta-analysis
Authors: Webb Kevin L. , Gorman Ellen K. , Morkeberg Olaf H. , Klassen Stephen A. , Regimbal Riley J. , Wiggins Chad C. , Joyner Michael J. , Hammer Shane M. , Senefeld Jonathon W.
Published: October 2023

Objective

There is widespread agreement about the key role of hemoglobin for oxygen transport. Both observational and interventional studies have examined the relationship between hemoglobin levels and maximal oxygen uptake (V˙O2max) in humans. However, there exists considerable variability in the scientific literature regarding the potential relationship between hemoglobin andV˙O2max. Thus, we aimed to provide a comprehensive analysis of the diverse literature and examine the relationship between hemoglobin levels (hemoglobin concentration and mass) andV˙O2max(absolute and relativeV˙O2max) among both observational and interventional studies.

Methods

A systematic search was performed on December 6th, 2021. The study procedures and reporting of findings followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Article selection and data abstraction were performed in duplicate by two independent reviewers. Primary outcomes were hemoglobin levels andV˙O2maxvalues (absolute and relative). For observational studies, meta-regression models were performed to examine the relationship between hemoglobin levels andV˙O2maxvalues. For interventional studies, meta-analysis models were performed to determine the change inV˙O2maxvalues (standard paired difference) associated with interventions designed to modify hemoglobin levels orV˙O2max. Meta-regression models were then performed to determine the relationship between a change in hemoglobin levels and the change inV˙O2maxvalues.

Results

Data from 384 studies (226 observational studies and 158 interventional studies) were examined. For observational data, there was a positive association between absoluteV˙O2maxand hemoglobin levels (hemoglobin concentration, hemoglobin mass, and hematocrit (P<0.001 for all)). Prespecified subgroup analyses demonstrated no apparent sex-related differences among these relationships. For interventional data, there was a positive association between the change of absoluteV˙O2max(standard paired difference) and the change in hemoglobin levels (hemoglobin concentration (P<0.0001) and hemoglobin mass (P= 0.006)).

Conclusion

These findings suggest thatV˙O2maxvalues are closely associated with hemoglobin levels among both observational and interventional studies. Although our findings suggest a lack of sex differences in these relationships, there were limited studies incorporating females or stratifying results by biological sex.
Confidence does not mediate a relationship between owner experience and likelihood of using weight management approaches for native ponies
Authors: Ward Ashley B. , Harris Patricia A. , Argo Caroline McG. , Watson Christine A. , Burns Neil M. , Neacsu Madalina , Russell Wendy R. , Grove-White Dai , Morrison Philippa K.
Published: October 2023

Native ponies are at increased risk of obesity and metabolic perturbations, such as insulin dysregulation (ID), a key risk factor for endocrinopathic laminitis. Management and feeding practices can be adapted to maintain healthy body condition and support metabolic health, but owners may inadvertently provide their ponies with inappropriate management leading to obesity and exacerbating risk of metabolic disease. Adoption of preventative weight management approaches (WMAs), including regular monitoring of body condition, providing appropriate preserved forage, promoting seasonal weight loss, and using exercise accordingly, are key in supporting native ponies’ metabolic health. The factors influencing the adoption of WMAs, such as owners’ experience and confidence, require exploration. The aim of the current study was to understand factors influencing owners’ likelihood to undertake certain WMAs, to develop our understanding of suitable intervention targets. A total of 571 responses to an online cross-sectional questionnaire were analysed. Mediation analysis revealed that whilst long term (≥20 years) experience caring for native ponies was associated with owners increased, self-reported confidence in identifying disease and managing their native ponies, this did not translate to an increased likelihood of implementing WMAs. Conversely, respondents who managed ponies with dietary requirements related to obesity, laminitis, or equine metabolic syndrome were more likely to use WMAs related to feeding, seasonal weight management and exercise. Owner confidence was assessed and rejected as a mediator of the relationship between experience and WMA use. These results highlight the need for further work that elucidates the pathways leading owners to undertake action against obesity without the need for ponies to develop overt disease, as well as suggesting a need for long term managers of native ponies to update management practices with preventative care as the focus.