bluuebunny/crossref_metadata_2025 huggingface dataset:
Tendon healing: a concise review on cellular and molecular mechanisms with a particular focus on the Achilles tendon
Authors: Schulze-Tanzil Gundula G. , Delgado Cáceres Manuel , Stange Richard , Wildemann Britt , Docheva Denitsa
Published: August 2022

Tendon is a bradytrophic and hypovascular tissue, hence, healing remains a major challenge. The molecular key events involved in successful repair have to be unravelled to develop novel strategies that reduce the risk of unfavourable outcomes such as non-healing, adhesion formation, and scarring. This review will consider the diverse pathophysiological features of tendon-derived cells that lead to failed healing, including misrouted differentiation (e.g. de- or transdifferentiation) and premature cell senescence, as well as the loss of functional progenitors. Many of these features can be attributed to disturbed cell-extracellular matrix (ECM) or unbalanced soluble mediators involving not only resident tendon cells, but also the cross-talk with immigrating immune cell populations. Unrestrained post-traumatic inflammation could hinder successful healing. Pro-angiogenic mediators trigger hypervascularization and lead to persistence of an immature repair tissue, which does not provide sufficient mechano-competence. Tendon repair tissue needs to achieve an ECM composition, structure, strength, and stiffness that resembles the undamaged highly hierarchically ordered tendon ECM. Adequate mechano-sensation and -transduction by tendon cells orchestrate ECM synthesis, stabilization by cross-linking, and remodelling as a prerequisite for the adaptation to the increased mechanical challenges during healing. Lastly, this review will discuss, from the cell biological point of view, possible optimization strategies for augmenting Achilles tendon (AT) healing outcomes, including adapted mechanostimulation and novel approaches by restraining neoangiogenesis, modifying stem cell niche parameters, tissue engineering, the modulation of the inflammatory cells, and the application of stimulatory factors.

Cite this article: Bone Joint Res 2022;11(8):561–574.
Design of a compact off-axis freeform three-mirror system in a circular configuration
Authors: Zhu Deyan , Hu Zijia , Yan Junhua , Xu Zhenyu , Cao Anjie , Su Jingqin
Published: August 2022

A compact off-axis three-mirror system, especially with a wide field of view and small

f

-number, continues to present challenges in the optical design field. To design a compact off-axis three-mirror system based on a freeform surface, an optimization method with a circular configuration and four parameters is proposed. In the proposed method, the

f

-number and angles of mirrors are combined to optimize and achieve high-quality imaging, which means the modulation transfer function is close to the diffraction limit. To evaluate the performance of the proposed method, four design examples with different fields of view (

4

∘

×

4

∘

,

6

∘

×

6

∘

) and

f

-numbers (2, 1.75) were created. The results showed that the compact off-axis three-mirror system based on a freeform surface can be designed with a wide field of view, small

f

-number, and high-quality imaging using the proposed method. Unlike other design methods, the surface parameters of mirrors are obtained with only one calculation and are close to the final optimization results, which saves both time and resources for optimization. The findings indicate that the method is accurate and effective for designing compact off-axis three-mirror systems with freeform surfaces.
Secret sharing scheme based on spread spectrum ghost imaging
Authors: Liu Jinfen , Wang Le , Zhao Shengmei
Published: August 2022

(
n
,
n
)

secret sharing is a procedure for splitting the key into several pieces so that no subset is sufficient to read the encrypted message except the entire one. In this paper, we propose a novel, to the best of our knowledge, secret sharing scheme based on spread spectrum ghost imaging (SSGI). In the scheme, a dealer divides a secret key, which is obtained by a modulo 2 addition over

n

sequences from a Hadamard matrix, into

n

pieces to

n

participants, and then the dealer uses the secret key as a direct sequence code to encrypt an image using the SSGI method. The resultant bucket signal, as the ciphertext, is then shared with

n

participants, and the modulated speckle patterns in SSGI are also transmitted to

n

participants by private channels for preventing eavesdropping. An independent signal is used as a protective signal to prevent the information leakage in SSGI. In the decryption process, only if all participants are honest and cooperative, the secret key can be obtained; thus, the ciphertext can be decrypted to the correct image using the second-order correlation algorithm. Otherwise, the image information cannot be extracted. The theoretical analysis shows that the probability of finding out others’ pieces for successfully reconstructing the image for one dishonest participant is

(

1

/

2
N

)

n
−
1

, where

N

is the length of the secret key, and

n

is the number of participants. The simulation and experimental results demonstrate that the proposed scheme has a stronger data security capacity in optical information encryption.
Broadband devices for a polarization converter based on optical metasurfaces
Authors: Wu Zhixiang , Zou Yiyang , Deng Hu , Xiong Liang , Liu Quancheng , Shang Liping
Published: August 2022

Devices employed for optical polarization conversion are widely used in the areas of optical focusing, optical imaging, and microscopy. To circumvent the problems of traditional optical polarization conversion devices, such as a narrow bandwidth, bulky size, and integration difficulties, a linear–radial polarization converter (LRPC) method based on optical metasurfaces is proposed. For a visible wavelength, i.e., 

λ
=

632.8

n
m

, an all-dielectric half-wave plate and a LRPC with a size of

40

λ

(25.312 µm) are designed. The simulated results demonstrate that the LRPC creates a radially polarized wave from a linearly polarized wave in the wavelength range of 620–680 nm. In addition, a cylindrical vectorial wave with different polarizations can be generated via an adjustment of the polarization direction of the incident wave. These types of polarization converters have the important advantage of high transmittance, while also being ultra-thin and easy to integrate. They are expected to be suitable for miniaturized and integrated optical devices.
Real-time pose estimation for an underwater object combined with deep learning and prior information
Authors: Ge Xianwei , Chi Shukai , Jia Wei , Jiang Ke
Published: August 2022

At present, the underwater autonomous operation based on monocular vision has poor accuracy and low intelligence, due mainly to the low accuracy of pose estimation. To solve this problem, we propose a real-time pose estimation method for underwater cylinders and cuboids. The first challenge in processing underwater images is image degradation, which is overcome by using a scale-optimized dark channel prior dehazing algorithm. The lightweight improved You Only Look Once v5 is used to obtain the pixel information of the four control points and obtain the bounding box close to the edge of the object, which makes the pose estimation more accurate. We then propose an underwater optical imaging model that overcomes the challenges posed by refraction. Finally, the improved algorithm based on the perspective-n-point problem is used to estimate the pose of the object in real time. We deployed the algorithm in the edge computing device NVIDIA Jetson TX2 and achieved excellent performance. The experimental results show that our method can achieve high-precision monocular pose estimation without producing a large-scale pose dataset, and can be used to provide reliable information for underwater autonomous operation tasks.
High range resolution wideband terahertz FMCW radar with a large depth of field
Authors: Hu Weidong , Xu Zhihao , Jiang Huanyu , Liu Yang , Yao Zhiyu , Zhang Kaiqi , Ligthart Leo P.
Published: August 2022

Terahertz frequency modulation continuous wave (THz FMCW) imaging technology has been widely used in non-destructive testing (NDT) applications of non-metallic materials. However, THz FMCW real-aperture radar usually has a narrow bandwidth and small depth of field, thus restricting the application of THz FMCW NDT. In this paper, a wideband THz signal (220–500 GHz) generation method is proposed by time-division multiplexing. Moreover, a dual-band quasi-optical design with a large depth of field is proposed based on the THz Bessel beam, and a high-quality range profile is obtained. Especially, a signal fusion extended Fourier analysis algorithm without prior knowledge is proposed to further enhance the range profile accuracy, which improves the range resolution to 0.28 mm (

λ

/

3

, center frequency 360 GHz). The effectiveness and advantages of the proposed system are verified by artificially constructing composite materials.
Fast algorithms for nonlinear and constrained phase retrieval in near-field X-ray holography based on Tikhonov regularization
Authors: Huhn Simon , Lohse Leon Merten , Lucht Jens , Salditt Tim
Published: August 2022

Based on phase retrieval, lensless coherent imaging and in particular holography offers quantitative phase and amplitude images. This is of particular importance for spectral ranges where suitable lenses are challenging, such as for hard x-rays. Here, we propose a phase retrieval approach for inline x-ray holography based on Tikhonov regularization applied to the full nonlinear forward model of image formation. The approach can be seen as a nonlinear generalization of the well-established contrast transfer function (CTF) reconstruction method. While similar methods have been proposed before, the current work achieves nonlinear, constrained phase retrieval at competitive computation times. We thus enable high-throughput imaging of optically strong objects beyond the scope of CTF. Using different examples of inline holograms obtained from illumination by a x-ray waveguide-source, we demonstrate superior image quality even for samples which do not obey the assumption of a weakly varying phase. Since the presented approach does not rely on linearization, we expect it to be well suited also for other probes such as visible light or electrons, which often exhibit strong phase interaction.
Compact double-pass Echelle spectrometer employing a crossed diffraction grating
Authors: Kraus Matthias , Hönle Tobias , Förster Erik , Sadlowski Patrick , Stumpf Daniela , Schöneberg Anja , Laue Benjamin , Brüning Robert , Hillmer Hartmut , Brunner Robert
Published: August 2022

This contribution presents the design and implementation of a compact and robust Echelle-inspired cross-grating spectrometer which is arranged as a double pass setup. This allows use of the employed refractive elements for collimation of the incoming light and, after diffraction at the reflective crossed diffraction grating, for imaging the diffracted light onto the detector. The crossed diffraction grating combines the two dispersive functionalities of a classical Echelle spectrometer in a single element and is therefore formed by a superposition of two blazed linear gratings which are oriented perpendicularly. The refractive elements and the plane grating are arranged in a rigid objective group which is beneficial in terms of stability and robustness. The experimental tests prove that the designed resolving power of more than 300 is achieved for the addressed spectrum ranging from 400 nm to 1100 nm by using an entrance pinhole diameter of 105 µm. The utilization of a single mode fiber increases the resolving power to more than 1000, but leads to longer acquisition times.
Thermal evaporated group IV Ge(Sn)-on-Si terahertz photoconductive antenna
Authors: Chen Wang-Chien , Yang Shang-Hua
Published: August 2022

We have experimentally demonstrated thermal evaporated group IV Ge1-xSnx-on-Si terahertz (THz) photoconductive antennas (PCA) pumped by an Er-doped femtosecond laser for broadband THz generation. The Ge1-xSnx THz PCAs, free from material epitaxial growth methods, can offer comparable material properties in photocarrier generation, transportation, recombination, and the collection as group III-V THz PCAs. At the optical pumping power of 90 mW and a bias voltage of 40V, the Ge1-xSnx THz PCAs have achieved a broadband spectrum over 1.5 THz with a 40 dB signal-to-noise ratio (SNR). This CMOS-compatible group IV THz source can be monolithically integrated on the Si photonic platform, paving the way toward THz system-on-chip (SoC) for many on-site applications in the non-destructive evaluation, biomedical imaging, and industrial inspections.
Experimental demonstration of synchronous privacy enhanced chaotic temporal phase en/decryption for high speed secure optical communication
Authors: Gao Zhensen , Wu Qiongqiong , Liao Lei , Su Biao , Gao Xulin , Fu Songnian , Li Zhaohui , Wang Yuncai , Qin Yuwen
Published: August 2022

Protecting confidential high speed optical signal transmission at the lowest physical layer is a critical challenge for modern fiber-optic communication systems. In this paper, we experimentally demonstrate a novel synchronous privacy enhanced chaotic temporal phase en/decryption scheme for high-speed physical layer secure optical communication. A remote chaos synchronization architecture relying on common source signal driving and private response hardware modules comprising of dispersive components and slave lasers is employed to generate synchronized private chaotic en/decryption signals, and simultaneously suppress residual driving-response correlation for enhancing the security. A proof-of-principle demonstration by secure transmission of a 28 Gb/s on-off-keying modulated confidential signal over 100 km single mode fiber link based on the private chaotic temporal phase en/decryption scheme is successfully achieved. The demonstrated hardware optical en/decryption approach may provide a promising way towards future ultra-high speed physical layer secure optical communication systems.
Background-penalty-free waveguide enhancement of CARS signal in air-filled anti-resonance hollow-core fiber
Authors: Bahari Aysan , Sower Kyle , Wang Kai , Han Zehua , Florence James , Wang Yingying , Gao Shoufei , Howard Lee Ho Wai , Scully Marlan , Zheltikov Aleksei , Sokolov Alexei
Published: August 2022

We study coherent anti-Stokes Raman spectroscopy in air-filled anti-resonance hollow-core photonic crystal fiber, otherwise known as “revolver” fiber. We compare the vibrational coherent anti-Stokes Raman signal of N2, at ∼2331 cm−1, generated in ambient air (no fiber present), with the one generated in a 2.96 cm of a revolver fiber. We show a ∼170 times enhancement for the signal produced in the fiber, due to an increased interaction path. Remarkably, the N2 signal obtained in the revolver fiber shows near-zero non-resonant background, due to near-zero overlap between the laser field and the fiber cladding. Through our study, we find that the revolver fiber properties make it an ideal candidate for the coherent Raman spectroscopy signal enhancement.
Quadraxial metamaterial
Authors: Sakhno D. , Koreshin E. , Belov P.
Published: August 2022

We study the dispersion of electromagnetic waves in a spatially dispersive metamaterial with Lorentz-like dependence of principal permittivity tensor components on the respective components of the wave vector performing the analysis of isofrequency contours. The considered permittivity tensor describes a triple non-connected wire medium. It is demonstrated that the metamaterial has four optic axes in the frequency range below the artificial plasma frequency. The directions of the optical axes do not depend on frequency and coincide with the diagonals of quadrants. The conical refraction effect is observed for all four optic axes.
Over-20-octaves-bandwidth ultralow-intensity-noise 1064-nm single-frequency fiber laser based on a comprehensive all-optical technique
Authors: Sun Yuxin , Zhao Qilai , Wang Changhe , Zeng Chun , Lin Wei , Yang Changsheng , Feng Zhouming , Zhang Qinyuan , Yang Zhongmin , Xu Shanhui
Published: August 2022

An over-20-octaves-bandwidth ultralow-intensity-noise 1064-nm single-frequency fiber laser (SFFL) is demonstrated based on a comprehensive all-optical technique. With a joint action of booster optical amplifier (BOA) and reflective Yb-doped fiber amplifier (RYDFA), two-fold optical gain saturation effects, respectively occurring in the media of semiconductor and fiber, have been synthetically leveraged. Benefiting from the gain dynamics in complementary time scales, i.e., nanosecond-order carrier lifetime in BOA and millisecond-order upper-level lifetime in RYDFA, the relative intensity noise (RIN) is reduced to −150 dB/Hz from 0.2 kHz to 350 MHz, which exceeds 20-octaves bandwidth. Remarkably, a maximum suppressing ratio of >54 dB is obtained, and the RIN in the range of 0.09–10 GHz reaches −161 dB/Hz which is only 2.3 dB above the shot-noise limit. This broad-bandwidth ultralow-intensity-noise SFFL can serve as an important building block for squeezed light generation, space laser communication, space gravitational wave detection, etc.
Silicon oxynitride platform for linear and nonlinear photonics at NIR wavelengths
Authors: Piccoli Gioele , Sanna Matteo , Borghi Massimo , Pavesi Lorenzo , Ghulinyan Mher
Published: August 2022

The development of versatile and novel material platforms for integrated photonics is of prime importance in the perspective of future applications of photonic integrated circuits for quantum information and sensing. Here we present a low-loss material platform based on high-refractive index silicon oxynitride (SiON), which offers significant characteristics for linear and non-linear optics applications in a wide range of red/near-infrared wavelengths. The demonstrated propagation loss <1.5 dB/cm for visible wavelengths enables the realization of long and intricate circuitry for photon manipulations, as well as the realization of high quality factor resonators. In addition, the proposed SiON shows a high nonlinear index of 10−19 m2/W, improving the strength of nonlinear effects exploitable for on-chip photon generation schemes.
Laser damage mechanism and threshold improvement of nonlinear optical La3Ga5.5Nb0.5O14 crystal for a mid-infrared high-intensity laser
Authors: Wang Yuzhou , Liang Fei , Lu Dazhi , Wang Shuxian , Wang Jiyang , Yu Haohai , Zhang Huaijin
Published: August 2022

Laser damage threshold (LDT) is critical for optical devices in high-intensity laser applications. Understanding the influence mechanism of a high-intensity laser on optical materials is principal for improving the materials’ LDTs. Here, the LDT of La3Ga5.5Nb0.5O14 (LGN) crystals, the most promising nonlinear optical material for mid-infrared optical parametric chirped-pulse amplification (OPCPA), were studied, and its laser damage mechanism was elucidated. Oxygen vacancies in different ligands have important and distinct effects on LDTs and introduce defect levels, playing primary roles in the reduction of LDTs by the absorption of electrons in the conduction bands. The formation of F-centers also decreases LDTs via two-photon absorption. In addition, the linear absorption of free electrons in the conduction bands contributes more than the two-photon absorption, induced by the defect level, in the nanosecond laser damage process. By annealing in optimized conditions, the 0% laser damage probability of the LGN crystals was measured up to 13.1 J/cm2, which is a 24% improvement compared with that of the as-grown sample, and the highest of the mid-infrared nonlinear optical crystals. The results can not only lead to further improvements in the laser amplification properties in OPCPA systems but also inspire further studies on the application of optical materials in high-intensity lasers.
Comprehensive analysis of the circadian nuclear and cytoplasmic transcriptome in mouse liver
Authors: Hurni Clémence , Weger Benjamin D. , Gobet Cédric , Naef Felix
Published: August 2022

In eukaryotes, RNA is synthesised in the nucleus, spliced, and exported to the cytoplasm where it is translated and finally degraded. Any of these steps could be subject to temporal regulation during the circadian cycle, resulting in daily fluctuations of RNA accumulation and affecting the distribution of transcripts in different subcellular compartments. Our study analysed the nuclear and cytoplasmic, poly(A) and total transcriptomes of mouse livers collected over the course of a day. These data provide a genome-wide temporal inventory of enrichment in subcellular RNA, and revealed specific signatures of splicing, nuclear export and cytoplasmic mRNA stability related to transcript and gene lengths. Combined with a mathematical model describing rhythmic RNA profiles, we could test the rhythmicity of export rates and cytoplasmic degradation rates of approximately 1400 genes. With nuclear export times usually much shorter than cytoplasmic half-lives, we found that nuclear export contributes to the modulation and generation of rhythmic profiles of 10% of the cycling nuclear mRNAs. This study contributes to a better understanding of the dynamic regulation of the transcriptome during the day-night cycle.
A controlled study to assess the effects of a Fast Track (FT) service delivery model among stable HIV patients in Lusaka Zambia
Authors: Bolton Moore Carolyn , Pry Jake M. , Mukumbwa-Mwenechanya Mpande , Eshun-Wilson Ingrid , Topp Stephanie , Mwamba Chanda , Roy Monika , Sohn Hojoon , Dowdy David W. , Padian Nancy , Holmes Charles B. , Geng Elvin H. , Sikazwe Izukanji
Published: August 2022

Fast Track models—in which patients coming to facility to pick up medications minimize waiting times through foregoing clinical review and collecting pre-packaged medications—present a potential strategy to reduce the burden of treatment. We examine effects of a Fast Track model (FT) in a real-world clinical HIV treatment program on retention to care comparing two clinics initiating FT care to five similar (in size and health care level), standard of care clinics in Zambia. Within each clinic, we selected a systematic sample of patients meeting FT eligibility to follow prospectively for retention using both electronic medical records as well as targeted chart review. We used a variety of methods including Kaplan Meier (KM) stratified by FT, to compare time to first late pick up, exploring late thresholds at >7, >14 and >28 days, Cox proportional hazards to describe associations between FT and late pick up, and linear mixed effects regression to assess the association of FT with medication possession ratio. A total of 905 participants were enrolled with a median age of 40 years (interquartile range [IQR]: 34–46 years), 67.1% were female, median CD4 count was 499 cells/mm3 (IQR: 354–691), and median time on ART was 5 years (IQR: 3–7). During the one-year follow-up period FT participants had a significantly reduced cumulative incidence of being >7 days late for ART pick-up (0.36, 95% confidence interval [CI]: 0.31–0.41) compared to control participants (0.66; 95% CI: 0.57–0.65). This trend held for >28 days late for ART pick-up appointments, at 23% (95% CI: 18%-28%) among intervention participants and 54% (95% CI: 47%-61%) among control participants. FT models significantly improved timely ART pick up among study participants. The apparent synergistic relationship between refill time and other elements of the FT suggest that FT may enhance the effects of extending visit spacing/multi-month scripting alone. ClinicalTrials.gov Identifier: NCT02776254 https://clinicaltrials.gov/ct2/show/NCT02776254.
Development and design of the first structured clinic-based program in lower resource settings to transition emerging adults with type 1 diabetes from pediatric to adult care
Authors: Cristello Sarteau Angelica , Peerzada Ariba , Goyal Alpesh , Praveen Pradeep A. , Tandon Nikhil
Published: August 2022

Introduction

Type 1 diabetes (T1D) is increasing in young people worldwide and more children in resource limited settings are living into adulthood. There is a need for rigorous testing and reporting of evidence-based and stakeholder-informed strategies that transition individuals with T1D from pediatric to adult care. We present the development of and design of the first structured transition program in Delhi, India, to inform similar efforts in India and resource limited settings.

Methods

The intervention development team included clinicians and researchers with expertise in T1D and the implementation context. To select intervention outcomes, establish intervention targets, and design session modules, we drew upon formative research conducted at prospective intervention implementation sites, consensus guidelines, and previous care transition and behavior change research conducted in developed settings. We used the Template for Intervention Description and Replication and GUIDance for the rEporting of intervention Development checklists to report the intervention and development process.

Results

The 15-month program (“PATHWAY”) includes five quarterly ~30 minute sessions delivered predominantly by diabetes educators at pediatric and adult clinics, which coincide with routine care visits. Primary program components include educational and behavioral sessions that address psychosocial drivers of clinic attendance and self-management, diabetes educators as transition coordinators and counselors, and a one-year “overlap period” of alternating visits between pediatric and adult providers.

Conclusions

We followed a systematic and transparent process to develop PATHWAY, which facilitated rich description of intervention context, guiding principles, targets, and components. Dependence on previously published program examples to design PATHWAY may have introduced challenges for program feasibility and effectiveness, underscoring the importance of input gathering from prospective intervention actors at multiple points in the development process. This detailed report in combination with future evaluations of PATHWAY support efforts to increase rigorous development and testing of strategies to improve outcomes among emerging adults with T1D.
Prevalence of bovine tuberculosis and characterization of the members of the Mycobacterium tuberculosis complex from slaughtered cattle in Rwanda
Authors: Ntivuguruzwa Jean Bosco , Michel Anita L. , Kolo Francis Babaman , Mwikarago Ivan Emil , Ngabonziza Jean Claude Semuto , van Heerden Henriette
Published: August 2022

Background

Bovine tuberculosis (bTB) is an endemic disease in Rwanda, but little is known about its prevalence and causative mycobacterial species. The disease causes tremendous losses in livestock and wildlife and remains a significant threat to public health.

Materials and methods

A cross-sectional study employing a systematic random sampling of cattle (n = 300) with the collection of retropharyngeal lymph nodes and tonsils (n = 300) irrespective of granulomatous lesions was carried out in six abattoirs to investigate the prevalence and identify mycobacterial species using culture, acid-fast bacteria staining, polymerase chain reaction, and GeneXpert assay. Individual risk factors and the origin of samples were analysed for association with the prevalence.

Findings

Of the 300 sample pools, six were collected with visible TB-like lesions. Our findings demonstrated the presence ofMycobacterium tuberculosiscomplex (MTBC) in 1.7% (5/300) of sampled slaughtered cattle.Mycobacterium boviswas isolated from 1.3% (4/300) animals while one case was caused by a rifampicin-resistant (RR)M.tuberculosis. Non-tuberculous mycobacteria were identified in 12.0% (36/300) of the sampled cattle. There were no significant associations between the prevalence and abattoir category, age, sex, and breeds of slaughtered cattle.

Conclusions

This study is the first in Rwanda to isolate bothM.bovisand RRM.tuberculosisin slaughtered cattle indicating that bTB is present in Rwanda with a low prevalence. The isolation of RRM.tuberculosisfrom cattle indicates possible zooanthroponotic transmission ofM.tuberculosisand close human-cattle contact. To protect humans against occupational zoonotic diseases, it is essential to control bTB in cattle and raise the awareness among all occupational groups as well as reinforce biosafety at the farm level and in the abattoirs.
Experiences and challenges of parents caring for children with attention-deficit hyperactivity disorder: A qualitative study in Dar es salaam, Tanzania
Authors: Ching’oma Charles Daud , Mkoka Dickson Ally , Ambikile Joel Seme , Iseselo Masunga Kidula
Published: August 2022

Background

Attention-deficit hyperactivity disorder (ADHD) is the most common neurobehavioral childhood disorder. Children with ADHD are difficult to handle due to the symptoms causing great impairments such as inattention, hyperactivity compared to other childhood mental disorders. Having a child with ADHD is a stressful situation as it impacts the whole family. However, little is known about the experiences and challenges of parents caring for children with ADHD in low and middle-income countries such as Tanzania. Thus, this study explored the experiences and challenges of parents caring for children with ADHD in Dar es Salaam, Tanzania.

Methods

We conducted a qualitative descriptive study involving 16 parents of children with ADHD at Muhimbili National Hospital (MNH). We used the purposive sampling technique to obtain the participants. In-depth interviews, using a semi-structured interview guide, were used to collect data. Audio-recorded data were transcribed, translated, and analysed using qualitative content analysis.

Results

Parents experienced difficulties in handling the children whose level of functioning was impaired due to abnormal and disruptive behaviour such as not being able to follow parental instructions. Psychological problems were also experienced due to caring demands exacerbated by lack of support and stigma from the community. Moreover, there were disruptions in family functioning and social interactions among family members due to the children’s behaviour. Lastly, too much time and family resources spent to fulfil the needs of these children culminated into disruption in economic activities that negatively affected everyday life.

Conclusion

Parents struggle to meet and cope with care demands posed by children with ADHD. The disruptive nature of ADHD symptoms presents a unique caring challenge different from those experienced with other childhood mental illnesses. To address these challenges, a collaborative approach among key stakeholders such as the government, health care professionals, and non-governmental organizations, is needed.
Structural equation model of the relationship between functional ability, mental health, and quality of life in older adults living alone
Authors: Yi YuMi , Park Yeon-Hwan
Published: August 2022

Aims

Living alone, a reality in an increasing number of older adults recently, is a risk factor for low quality of life. This study identified the predictors of quality of life in older adults living alone based on mental health and the International Classification of Functioning, Disability, and Health.

Methods

This secondary data analysis used information from the 2018 Assessing the Requirements of Customized Health Care and Daily Living Support Services survey (N = 1,022), collected from adults aged ≥ 65 living alone in Siheung City, South Korea, from August to October 2018. The exogenous variables were body functions (hand grip strength, timed “up and go” test score, and body mass index), daily living activities (Korean Instrumental Activities of the Daily Living Scale), social activity participation (social activity engagement, neighbor contacts, and family contacts), and participation in economic activity (frequency). The endogenous variables were mental health (Geriatric Depression Scale Short Form—Korean Version and UCLA Loneliness Scale) and quality of life (EuroQoL-5 Dimension-3 Level and EuroQoL-Visual Analog Scale).

Results

After modifying the hypothetical model, which had failed to satisfy the recommended fitness level, the (modified) model had good fitness indices Q (CMIN / df) 2.90, GFI 1, AGFI 1, RMSEA 0.04, CFI 0.90 and PCFI 0.53. Of the nine pathways of the modified model, five were statistically significant. Quality of life was affected by body functions, daily living activities, social activity participation, and mental health. These variables explained 68.2% of the factors affecting quality of life.

Conclusions

By highlighting the role of mental health, this model provides a useful framework for improving the quality of life of older adults who live alone and function at various levels in the community. Focusing on advancing mental health through body functions, daily living activities, and social activity participation can improve quality of life.
Structural elucidation of substrate-bound aminoglycoside acetyltransferase (3)-IIIa
Authors: Zieliński Michał , Blanchet Jonathan , Hailemariam Sophia , Berghuis Albert M.
Published: August 2022

Canonical aminoglycosides are a large group of antibiotics, where the part of chemical diversity stems from the substitution of the neamine ring system on positions 5 and 6. Certain aminoglycoside modifying enzymes can modify a broad range of 4,5- and 4,6-disubstituted aminoglycosides, with some as many as 15. This study presents the structural and kinetic results describing a promiscuous aminoglycoside acetyltransferase AAC(3)-IIIa. This enzyme has been crystallized in ternary complex with coenzyme A and 4,5- and 4,6-disubstituted aminoglycosides. We have followed up this work with kinetic characterization utilizing a panel of diverse aminoglycosides, including a next-generation aminoglycoside, plazomicin. Lastly, we observed an alternative binding mode of gentamicin in the aminoglycoside binding site, which was proven to be a crystallographic artifact based on mutagenesis.
Creeping disaster along the U.S. coastline: Understanding exposure to sea level rise and hurricanes through historical development
Authors: Braswell Anna E. , Leyk Stefan , Connor Dylan S. , Uhl Johannes H.
Published: August 2022

Current estimates of U.S. property at risk of coastal hazards and sea level rise (SLR) are staggering—evaluated at over a trillion U.S. dollars. Despite being enormous in the aggregate, potential losses due to SLR depend on mitigation, adaptation, and exposure and are highly uneven in their distribution across coastal cities. We provide the first analysis of how changes in exposure (howandwhen) have unfolded over more than a century of coastal urban development in the United States. We do so by leveraging new historical settlement layers from the Historical Settlement Data Compilation for the U.S. (HISDAC-US) to examine building patterns within and between the SLR zones of the conterminous United States since the early twentieth century. Our analysis reveals that SLR zones developed faster and continue to have higher structure density than non-coastal, urban, and inland areas. These patterns are particularly prominent in locations affected by hurricanes. However, density levels in historically less-developed coastal areas are now quickly converging on early settled SLR zones, many of which have reached building saturation. These “saturation effects” suggest that adaptation polices targeting existing buildings and developed areas are likely to grow in importance relative to the protection of previously undeveloped land.
Correlative tomography and authentication features of a shrunken head (tsantsa)
Authors: Poeta Lauren September , Ordóñez Maria Patricia , Fournier Eric , Nelson Andrew John
Published: August 2022

Museum personnel and the general public have become quite familiar with the presence of shrunken heads in museum collections, but the procedures to authenticate the history and origin of these unique cultural items are not yet reliable. These shrunken heads, calledtsantsas, are meant to be the cultural material remains of ceremonies conducted by the Shuar and Achuar Peoples of South America. This project seeks to integrate the use of micro-computed tomography (micro-CT) scanning with methods used in previous studies (clinical computed tomography (CT) and visual inspections) to examine authentication procedures of shrunken heads (tsantsas) held in contemporary museum collections. We use a correlative tomographic approach using several scans at successively higher resolutions to determine whether atsantsawas created from human remains, and if so, what key features can best contribute to its authentication. Conclusively, our correlative tomographic approaches provide new insights into the determination process of whether atsantsawas created from real human remains or not. Also, this study questions whether the previously conceptualized dichotomy of ceremonial or commercial might be better thought of as a continuum of practice. Investigating and redefining the examination and authentication procedures oftsantsasis crucial for future ethical curation, management, and repatriation efforts of this unique cultural material of the Shuar and Achuar Peoples.
Respiratory pathogens during the COVID-19 pandemic: Alterations in detection and seasonality in Nashville, Tennessee
Authors: Haddadin Zaid , Spieker Andrew J. , Rahman Herdi , Rankin Danielle A. , Talj Rana , Yanis Ahmad , Amarin Justin Z. , Schmitz Jonathan , Chappell James , Halasa Natasha B.
Published: August 2022

Shortly after the implementation of community mitigation measures in response to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), sharp declines in respiratory syncytial virus and influenza circulation were noted; post-mitigation circulation of other respiratory pathogens has gone unexplored. We retrospectively analyzed all records of a provider-ordered multiplex test between April 1, 2018, and July 31, 2021, in Nashville, Tennessee, and we noted disrupted historical seasonal patterns for common respiratory pathogens during the SARS-CoV-2 pandemic.
Developing players for athlete leadership groups in professional football teams: Qualitative insights from head coaches and athlete leaders
Authors: Haddad Gina , O’Connor Donna
Published: August 2022

Athlete leadership groups (ALGs) are a widely used yet under researched approach to leadership in professional sports teams. Athlete Leadership Groups (ALGs) represent a shared athlete leadership model whereby a small group of players are selected as athlete leaders and appointed to a formal ‘leadership group’ (i.e., an ALG) that shares team leadership responsibilities with the coach. Although athlete leadership has been linked to improved team outcomes, inadequately trained athlete leaders can have a detrimental effect on team functioning and performance. The aim of this study was to provide coach and athlete leader’s perceptions of the development opportunities that have been afforded to players to prepare them for their role in an ALG. Semi-structured interviews were conducted with 16 head coaches and 14 players from leadership groups drawn from 17 teams across four professional football leagues (i.e., Super Rugby, National Rugby League, A League and Australian Football League) in Australia and New Zealand. Results illustrate that athlete leaders benefit from developing enhanced understanding of leadership as a multidimensional relational process, recognising various leadership styles, preferences, and how to leverage their influence with teammates. However, it is evident this theoretical knowledge alone is insufficient to equip players for a professional team ALG role. Players need opportunities to practice their developing leadership skills in authentic and appropriately challenging situations with support and facilitation. Findings point to the importance of systematic, individually tailored leadership development that includes scaffolded, structured experiential learning and meaningful interactions with other successful high-performance leaders. Further, this study reinforces the value of guided reflective practice in leadership development and how this process can enhance learning and transfer from leadership development initiatives. Finally, this study adds weight to calls from other researchers for coaches to be consistently intentional in employing leadership development strategies.
Human iPSC-derived astrocytes generated from donors with globoid cell leukodystrophy display phenotypes associated with disease
Authors: Lieberman Richard , Cortes Leslie K. , Gao Grace , Park Hyejung , Wang Bing , Jones Patrick L. , Hunter R. Bridge , Leonard John P. , Barker Robert H.
Published: August 2022

Globoid cell leukodystrophy (Krabbe disease) is a fatal neurodegenerative, demyelinating disease caused by dysfunctional activity of galactosylceramidase (GALC), leading to the accumulation of glycosphingolipids including psychosine. While oligodendrocytes have been extensively studied due to their high levels of GALC, the contribution of astrocytes to disease pathogenesis remains to be fully elucidated. In the current study, we generated induced pluripotent stem cells (iPSCs) from two donors with infantile onset Krabbe disease and differentiated them into cultures of astrocytes. Krabbe astrocytes recapitulated many key findings observed in humans and rodent models of the disease, including the accumulation of psychosine and elevated expression of the pro-inflammatory cytokine IL-6. Unexpectedly, Krabbe astrocytes had higher levels of glucosylceramide and ceramide, and displayed compensatory changes in genes encoding glycosphingolipid biosynthetic enzymes, suggesting a shunting away from the galactosylceramide and psychosine pathway. In co-culture, Krabbe astrocytes negatively impacted the survival of iPSC-derived human neurons while enhancing survival of iPSC-derived human microglia. Substrate reduction approaches targeting either glucosylceramide synthase or serine palmitoyltransferase to reduce the sphingolipids elevated in Krabbe astrocytes failed to rescue their detrimental impact on neuron survival. Our results suggest that astrocytes may contribute to the progression of Krabbe disease and warrant further exploration into their role as therapeutic targets.
TRANSALUD: A qualitative study of the healthcare experiences of transgender people in Barcelona (Spain)
Authors: Santander-Morillas Kevin , Leyva-Moral Juan M. , Villar-Salgueiro Marta , Aguayo-González Mariela , Téllez-Velasco David , Granel-Giménez Nina , Gómez-Ibáñez Rebeca
Published: August 2022

Transgender identities are still considered a psychiatric pathology in many countries according to the prevailing biomedical model. However, in recent years, this pathologizing vision has begun to shift towards a perspective that focuses on the diversity of transgender peoples’ experiences. However, some transgender people still face denial of services, discrimination, harassment, and even violence by healthcare professionals, causing them to avoid seeking ongoing or preventive healthcare. This article describes the health experiences of transgender people in Barcelona regarding their access and use of non-specialized health services. Semi-structured interviews were conducted using a descriptive phenomenological approach with sixteen transgender people between December 2018 and July 2019. The data were analyzed descriptively and thematically following the method proposed by Colaizzi with the help of the Atlas.ti8 software. Transgender people care experiences were divided into three categories: overcoming obstacles, training queries, and coping strategies. Participants identified negative experiences and difficulties with the health system due to healthcare providers’ lack of competence. Discriminatory, authoritarian, and paternalist behaviors are still present and hinder the therapeutic relationship, care, and access to healthcare services. There is a fundamental need for the depathologization of transgender reality and training for healthcare professionals in the field of sexual diversity. Training in sexual and gender diversity must be included in the curricula of university courses in the health sciences.
A feather hydrogen (δ2H) isoscape for Brazil
Authors: Alquezar Renata D. , Costa Fabio J. V. , Sena-Souza João Paulo , Nardoto Gabriela B. , Hobson Keith A.
Published: August 2022

Spatial patterns of stable isotopes in animal tissues or “isoscapes” can be used to investigate animal origins in a range of ecological and forensic investigations. Here, we developed a feather hydrogen isotope (δ2Hf) isoscape for Brazil based on 192 samples of feathers from the family Thraupidae from scientific collections. Raw values of δ2Hf ranged from -107.3 to +5.0‰, with higher values at the Caatinga biome (northeast Brazil) and lower values at the Amazon and Pantanal. A Random Forest (RF) method was used to model the spatial surface, using a range of environmental data as auxiliary variables. The RF model indicated a negative relationship between δ2Hf and Mean Annual Precipitation, Precipitation in the Warmest Quarter, and Annual Temperature Range and positive relationships for amount-weighted February-April precipitation δ2H (δ2Hp(Feb-April)) and Mean Annual Solar Radiation. Modelled δ2Hf values ranged from -85.7 to -13.6‰. Ours is the first δ2Hf isoscape for Brazil that can greatly assist our understanding of both ecological and biogeochemical processes controlling spatial variation in δ2H for this region. This isoscape can be used with caution, due to its poor predictive power (as found in other tropical regions) and can benefit from new sample input, new GNIP data, ecological and physiological studies, and keratin standard material better encompassing the range in feather samples from Brazil. So, we encourage new attempts to build more precise feather H isoscapes, as well as isoscapes based on other elements.
Prolactin at moderately increased levels confers a neuroprotective effect in non-secreting pituitary macroadenomas
Authors: Paul David A. , Rodrigue Alejandra , Contento Nicholas , Haber Sam , Hoang Ricky , Rahmani Redi , Hirad Adnan , Shafiq Ismat , Williams Zoë , Vates G. Edward
Published: August 2022

Context

Prolactin, a hormone synthesized by the anterior pituitary gland demonstrates promise as a neuroprotective agent, however, its role in humans and in vivo during injury is not fully understood.

Objective

To investigate whether elevated levels of prolactin attenuate injury to the retinal nerve fiber layer (RNFL) following compression of the optic chiasm in patients with a prolactin secreting pituitary macroadenoma (i.e., prolactinoma).

Design setting and participants

A retrospective cross-sectional study of all pituitary macroadenoma patients treated at a single institution between 2009 and 2019.

Main outcome measure(s)

Primary outcome measures included RNFL thickness, mean deviation, and prolactin levels for both prolactin-secreting and non-secreting pituitary macroadenoma patients.

Results

Sixty-six patients met inclusion criteria for this study (14 prolactin-secreting and 52 non-secreting macroadenoma patients). Of 52 non-secreting macroadenoma patients, 12 had moderate elevation of prolactin secondary to stalk effect. Patients with moderate elevation in prolactin demonstrated increased RNFL thickness compared to patients with normal prolactin levels (p < 0.01). Additionally, a significant positive relation between increasing levels of prolactin and RNFL thickness was identified in patients with moderate prolactin elevation (R = 0.51, p-value = 0.035). No significant difference was identified between prolactinoma patients and those with normal prolactin levels.

Conclusions

Moderately increased serum prolactin is associated with increased RNFL thickness when compared to controls. These associations are lost when serum prolactin is < 30 ng/ml or elevated in prolactinomas. This suggests a neuroprotective effect of prolactin at moderately increased levels in preserving retinal function during optic chiasm compression.