bluuebunny/crossref_metadata_2025 huggingface dataset:
Synchrony between daily rhythms of malaria parasites and hosts is driven by an essential amino acid
Authors: Prior Kimberley F. , Middleton Benita , Owolabi Alíz T.Y. , Westwood Mary L. , Holland Jacob , O'Donnell Aidan J. , Blackman Michael J. , Skene Debra J. , Reece Sarah E.
Published: July 2021

Background: Rapid asexual replication of blood stage malaria parasites is responsible for the severity of disease symptoms and fuels the production of transmission forms. Here, we demonstrate that the Plasmodium chabaudi’s schedule for asexual replication can be orchestrated by isoleucine, a metabolite provided to the parasite in periodic manner due to the host’s rhythmic intake of food.

Methods: We infect female C57BL/6 and Per1/2-null TTFL clock-disrupted mice with 1×105 red blood cells containing P. chabaudi (DK genotype). We perturb the timing of rhythms in asexual replication and host feeding-fasting cycles to identify nutrients with rhythms that match all combinations of host and parasite rhythms. We then test whether perturbing the availability of the best candidate nutrient in vitro elicits changes their schedule for asexual development.

Results: Our large-scale metabolomics experiment and follow up experiments reveal that only one metabolite - the amino acid isoleucine – fits criteria for a time-of-day cue used by parasites to set the schedule for replication. The response to isoleucine is a parasite strategy rather than solely the consequences of a constraint imposed by host rhythms, because unlike when parasites are deprived of other essential nutrients, they suffer no apparent costs from isoleucine withdrawal.

Conclusions: Overall, our data suggest parasites can use the daily rhythmicity of blood-isoleucine concentration to synchronise asexual development with the availability of isoleucine, and potentially other resources, that arrive in the blood in a periodic manner due to the host’s daily feeding-fasting cycle. Identifying both how and why parasites keep time opens avenues for interventions; interfering with the parasite’s time-keeping mechanism may stall replication, increasing the efficacy of drugs and immune responses, and could also prevent parasites from entering dormancy to tolerate drugs.
Maternal postnatal depression and offspring depression at age 24 years in a UK-birth cohort: the mediating role of maternal nurturing behaviours concerning feeding, crying and sleeping
Authors: Culpin Iryna , Hammerton Gemma , Bornstein Marc H. , Heron Jon , Evans Jonathan , Cadman Tim , Sallis Hannah M. , Tilling Kate , Stein Alan , Kwong Alex S.F. , Pearson Rebecca M.
Published: July 2021

Background: Maternal postnatal depression (PND) is a risk factor for offspring depression in adulthood. However, few longitudinal studies have examined the role of maternal nurturing parenting behaviours in the association between maternal PND and offspring depression in adulthood.

Methods: We examined pathways from maternal PND measured using self-reported Edinburgh Postnatal Depression Scale at 8 weeks to offspring ICD-10 depression diagnosed using the Clinical Interview Schedule-Revised computerised assessment at 24 years through maternal-reported nurturing behaviours concerning feeding, sleeping and crying measured from pregnancy to age 3 years 6 months in 5,881 members of the UK-based birth cohort study, the Avon Longitudinal Study of Parents and Children.  

Results: The fully adjusted model revealed an indirect effect from PND to adult offspring depression through the combination of all parenting factors (probit regression coefficient [B]=0.038, 95% confidence interval [CI] 0.005, 0.071); however, there was no evidence of a direct effect from early maternal PND to offspring depression once the indirect effect via parenting factors was accounted for (B=0.009, 95%CI -0.075, 0.093). Specificity analyses revealed indirect effects through maternal worries about feeding (B=0.019, 95%CI 0.003, 0.035, p=0.010) and maternal perceptions and responses to crying (B=0.018, 95%CI 0.004, 0.032, p=0.012).

Conclusions: The adverse impact of maternal PND on offspring depression in early adulthood was explained by maternal nurturing behaviours concerning feeding, crying and sleeping in early childhood. Residual confounding and measurement error likely limit reliable conclusions. If found causal, interventions providing support to reduce worries around maternal nurturing behaviours and treating depression could reduce adverse outcomes in adult offspring of depressed mothers.
Regulation of the Islamic Accounting Model in the Context of Russian Reality
Authors: Umarov Kh.
Published: July 2021

The article examines the economic model for the implementation of accounting standards in accordance with the religious beliefs of Islam, the activities of organizations involved in the implementation of Islamic principles of economics and their difficulties along the way. As well as, the possibility of implementing legislative initiatives and regulatory documents of the Islamic economy in the Russian financial market is being considered.
Intersection Operation on a Complex Plane
Authors: Girsh A.
Published: July 2021

Two plane algebraic curves intersect at the actual intersection points of these curves’ graphs. In addition to real intersection points, algebraic curves can also have imaginary intersection points. The total number of curves intersection points is equal to the product of their orders mn. The number of imaginary intersection points can be equal to or part of mn. The position of the actual intersection points is determined by the graphs of the curves, but the imaginary intersection points do not lie on the graphs of these curves, and their position on the plane remains unclear. This work aims to determine the geometry of imaginary intersection points, introduces into consideration the concept of imaginary complement for these algebraic curves in the intersection operation, determines the form of imaginary complements, which intersect at imaginary points. The visualization of imaginary complements clarifies the curves intersection picture, and the position of the imaginary intersection points becomes expected.
Education, recognition, support and collaboration
Authors: Marshall Sarah
Published: July 2021

Sarah Marshall introduces the virtual events, nursing award, member assistance programme and European collaborations offered to members of the British Society of Gastroenterology Nurses' Association
Clinicians' and nurses' documentation practices in palliative and hospice care
Authors: Natuhwera Germans , Rabwoni Martha , Ellis Peter , Merriman Anne
Published: July 2021

Background:

Health workers are likely to document patients' care inaccurately, especially when using new and revised case tools, and this could negatively impact patient care.

Aim:

To assess nurses' and clinicians' documentation practices when using a new patients' continuation case sheet (PCCS) and explore nurses' and clinicians' experiences regarding the documentation of patients' information in the new PCCS. The purpose of introducing the PCCS was to improve the continuity of care for patients attending clinics at which they were unlikely to consistently see the same clinician or nurse.

Method:

This was a mixed-methods study. The cross-sectional inquiry retrospectively reviewed 100 case notes of active patients in a hospice and palliative care programme. Data were collected using a structured questionnaire with constructs formulated from the new PCCS under study. The qualitative element was face-to-face, audio-recorded, open-ended interviews with a purposive sample of one palliative care clinician and four palliative care nurse specialists. Thematic analysis was used.

Results:

Patients' biogeographic information was missing in 5% to 10% case notes. Spiritual and psychosocial issues were not documented in 42.6% of patients' case notes and vital signs, in 49.2%. The poorest documentation practices were observed in the past medical history part of the PCCS, noted in 40%–63% of the 100 case notes included in this study. Four themes emerged from interviews with clinicians and nurses: (1) what remains unclear and challenges; (2) comparing the past with the present; (3) experiential thoughts, and; (4) transition and adapting to change.

Conclusion:

The PCCS seems to be a comprehensive and simple tool that can be used to document patients' information at subsequent visits. To increase its reliability and validity, clinicians and nurses need training on how to use it. Clinicians and nurses need to prioritise accurate and complete documentation of patient care in the PCCS to ensure quality care provision. This study should be extended to other sites using similar tools to ensure representative and generalisable findings.
Perception of spiritual care among palliative care nurses: cross-sectional study in eastern Turkey
Authors: Cengiz Zeliha , Olmaz Dilek , Turan Mensure
Published: July 2021

Background:

Spiritual care is an integral part of palliative care. A nurse's perception of spiritual care is an effective factor for giving spiritual care.

Aim:

To determine the perception of spiritual care and the variables that might affect the perception of spiritual care among palliative care nurses.

Methods:

This cross-sectional study included 51 nurses working in the palliative care units. Perceptions of spiritual care was measured with the Spiritual Support Perception Scale.

Findings:

The mean score of the perception of the spiritual care of the nurses was found to be 64.22±9.25. A negative correlation was found between the nurses' mean score of the perception of spiritual care and the number of patients to whom those nurses provided daily care.

Conclusion:

This study has found that palliative care nurses had a high level of perception of spiritual care. Based on the study results, it was determined that the number of patients receiving daily care was a predictor for the perception of spiritual care.
Effects of Sunlamp-Based Lighting Mode on Growth Performance, Survival Rate, Stress Response, and Oxidative Stress of Juvenile Chinese Soft-Shelled Turtles (Pelodiscus sinensis)in a Greenhouse
Authors: Li Haijun , Zhao Jian , Ji Baimin , Ye Zhangying , Zhu Songming , Zhou Caiping
Published: July 2021

Highlights

Sunlamps with UV and visible light were used in large-scale farming of Chinese soft-shelled turtles in a greenhouse.

The effects of lighting mode on the growth performance, survival rate, stress response, and oxidative stress of juvenile Chinese soft-shelled turtles were studied.

Lighting mode had significant impacts on survival rate, stress, and oxidative stress of Chinese soft-shelled turtles.

Lighting the basking area only was the optimal lighting mode and caused less stress for Chinese soft-shelled turtles.

Abstract. To investigate the effects of sunlamp-based lighting mode on the growth performance, survival rate, stress response, and oxidative stress of juvenile soft-shelled turtles in a greenhouse, four lighting modes with three replicates were used in this study: lighting the basking area and water simultaneously (LBW), lighting the water only (LW), lighting the basking area only (LB), and no light (NL). Results showed that the final weight, weight gain rate, and specific growth rate had no significant differences among treatments. The survival rate was significantly lower in LBW than in NL, while no significant differences were observed among NL, LB, and LW. On the physiological level, serum cortisol level was significantly lower in LB compared to the other two treatments with light, and glucose level was significantly lower in LB than in LW and NL. With regard to oxidative stress, indexes indicated that the turtles suffered less oxidative stress in LB. Glutathione peroxidase (GSH-PX) was significantly lower in LB compared to the other three treatments. Total antioxidant capacity (T-AOC) was significantly lower in LB, as well as in LW and NL, than in LBW, and no significant differences were found among LB, LW, and NL. Additionally, complement 3 (C3) was significantly higher in LB than in NL, which indicated that the turtles had higher immune-related protein in LB. On the whole, the results demonstrated that lighting mode had significant impacts on survival rate, stress response, and oxidative stress. It can be concluded that lighting the basking area only is the optimal lighting mode for soft-shelled turtles in a greenhouse. From the perspective of breeding welfare, soft-shelled turtles are suggested to be provided with a separate area for basking when cultured in a greenhouse. Keywords: Chinese soft-shelled turtle, Lighting mode, Oxidative stress, Stress response, Survival rate.
Performance and limitation estimation of a three-tap gated imaging sensor in wide field time-gated fluorescence lifetime imaging systems
Authors: Chang Yun-Tzu , Van Sieleghem Edward , Lee Jiwon , Van Dorpe Pol , Van Hoof Chris
Published: July 2021

In this paper, a computational performance analysis is presented of a wide-field time-gated fluorescence lifetime imaging microscope (FLIM) using practically realizable properties of the laser, sample, and a three-tap time-gated CMOS image sensor. The impact of these component-level properties on the accuracy and the precision of the measurement results are estimated and discussed based on Monte Carlo simulations. The correlation between the detector speed and the accuracy of the extracted fluorescence lifetime is studied, and the minimum required incident photoelectron number of each pixel is estimated for different detector speeds and different fluorescence lifetime measurements. In addition, the detection limits due to the dark current and the parasitic light sensitivity of the detector are also investigated. This work gives an overview of the required fluorescence emission condition as well as the required detector properties for a three-tap time-gated image sensor to achieve good FLIM data in biological applications.
Enlightening Arago–Poisson spot using structured light
Authors: Harland Matthew , Khonina Svetlana N. , Golub Ilya
Published: July 2021

We show that structured light can amplify the intensity of an Arago–Poisson bright spot, the cornerstone proof of the wave nature of light, by several orders of magnitude. Specifically, we use a thin annular beam produced by either an axicon–lens combination or two axicons to illuminate an opaque circular obstacle. Experimental results confirm the numerical calculations. By judiciously choosing our scheme’s parameters, the bright spot intensity can be higher than that of the original beam, meaning that structured light facilitates “focusing” of light behind an obstacle. This amplification, in addition to didactic elucidation of this classical effect, can find use in optical alignment/metrology, lithography, aberration measurements, as well as in basic science studies of the Arago–Poisson spot in matter waves.
Terahertz dielectric spectroscopy and solid immersion microscopy of ex vivo glioma model 101.8: brain tissue heterogeneity
Authors: Kucheryavenko A. S. , Chernomyrdin N. V. , Gavdush A. A. , Alekseeva A. I. , Nikitin P. V. , Dolganova I. N. , Karalkin P. A. , Khalansky A. S. , Spektor I. E. , Skorobogatiy M. , Tuchin V. V. , Zaytsev K. I.
Published: July 2021

Terahertz (THz) technology holds strong potential for the intraoperative label-free diagnosis of brain gliomas, aimed at ensuring their gross-total resection. Nevertheless, it is still far from clinical applications due to the limited knowledge about the THz-wave–brain tissue interactions. In this work, rat glioma model 101.8 was studied ex vivo using both the THz pulsed spectroscopy and the 0.15λ-resolution THz solid immersion microscopy (λ is a free-space wavelength). The considered homograft model mimics glioblastoma, possesses heterogeneous character, unclear margins, and microvascularity. Using the THz spectroscopy, effective THz optical properties of brain tissues were studied, as averaged within the diffraction-limited beam spot. Thus measured THz optical properties revealed a persistent difference between intact tissues and a tumor, along with fluctuations of the tissue response over the rat brain. The observed THz microscopic images showed heterogeneous character of brain tissues at the scale posed by the THz wavelengths, which is due to the distinct response of white and gray matters, the presence of different neurovascular structures, as well as due to the necrotic debris and hemorrhage in a tumor. Such heterogeneities might significantly complicate delineation of tumor margins during the intraoperative THz neurodiagnosis. The presented results for the first time pose the problem of studying the inhomogeneity of brain tissues that causes scattering of THz waves, as well as the urgent need to use the radiation transfer theory for describing the THz-wave — tissue interactions.
Waveguide-lattice-based architecture for multichannel optical transformations
Authors: Skryabin N. N. , Dyakonov I. V. , Saygin M. Yu. , Kulik S. P.
Published: July 2021

We consider waveguide lattices as the architecture to implement a wide range of multiport transformations. In this architecture, a particular transfer matrix is obtained by setting step-wise profiles of propagation constants experienced by a field evolving in a lattice. To investigate the capabilities of this architecture, we numerically study the implementation of random transfer matrices as well as several notable cases, such as the discrete Fourier transform, the Hadamard, and permutation matrices. We show that waveguide lattice schemes are more compact than their traditional lumped-parameter counterparts, thus the proposed architecture may be beneficial for photonic information processing systems of the future.
Polymer transfer technique for strain-activated emission in hexagonal boron nitride
Authors: Scheuer K. G. , Hornig G. J. , DeCorby R. G.
Published: July 2021

We present a hexagonal boron nitride (hBN) polymer-assisted transfer technique and discuss subtleties about the process. We then demonstrate localized emission from strained regions of the film draped over features on a prepatterned substrate. Notably, we provide insight into the brightness distribution of these emitters and show that the brightest emission is clearly localized to the underlyin­g substrate features rather than unintentional wrinkles present in the hBN film. Our results aide in the current discussion surrounding scalability of single photon emitter arrays.
Active meta-device for angular dispersion elimination of dual-polarized transmission windows
Authors: Bai Hui , Yan Mingbao , Wang He , Wang Jiafu , Zheng Lin , Li Chenchen , Qu Shaobo
Published: July 2021

Metasurface-based strategy of tailoring electromagnetic waves has aroused huge attention in both academic and engineering communities owing to great potential in a large portfolio of applications. Commonly, however, the artificially designed metasurfaces are sensitive to the oblique incident waves which results in the angular dispersion and inevitably deteriorates the performances. Here, we propose a paradigm of an active meta-device to effectively eliminate the angular dispersion in two orthogonal polarization states of transmission waves. By loading varactor diodes into a transmissive meta-atom, the transmission responses for traverse electric (TE) and traverse magnetic (TM) waves are actively tunable by a voltage-driven manner. Accordingly, the blue shifts of transmission windows can be ingeniously compensated via tailoring the corresponding dispersion characteristics of varactor diodes. A triple-layer meta-atom loaded with varactor diodes is designed as a dual-polarization proof-of-principle, in which the varactor diodes can be applied to independently control two polarization states. The numerical simulations and experimental verification are in good agreement, indicating the proposed paradigm possesses the potential in versatile applications, including radome, wireless communications, and other dispersionless systems.
Stable high power deep-uv enhancement cavity in ultra-high vacuum with fluoride coatings
Authors: Burkley Zakary , de Sousa Borges Lucas , Ohayon Ben , Golovizin Artem , Zhang Jesse , Crivelli Paolo
Published: July 2021

We demonstrate the superior performance of dielectric fluoride coatings versus oxide coatings in long term vacuum operation of a high power deep-ultraviolet enhancement cavity. In ultra-high vacuum (10−8 mbar), the fluoride optics can maintain up to 10 W of stable intracavity power on one hour time scales, a record-high at these vacuum levels, whereas for the oxide optics, we observe rapid degradation at lower intracavity powers with a rate that increases with power. After observing degradation in high vacuum, we can recover the fluoride and oxide optics with oxygen; however, this recovery process becomes ineffective after several applications. For the fluoride optics, we see that initial UV conditioning in an oxygen environment helps to improve the performances of the optics. In oxygen-rich environments from ∼10−4 mbar, the fluoride optics can stably maintain up to 20 W of intracavity power on several-hour time scales whereas for the oxide optics there is immediate degradation with a rate that increases with decreasing oxygen pressure.
Quantum interference control of perfect photon absorption in a three-level atom-cavity system
Authors: Guo Miaodi
Published: July 2021

We propose a scheme for controlling coherent photon absorption by electromagnetically induced transparency (EIT) in a three-level atom-cavity system. Coherent perfect absorption (CPA) occurs when time-reversed symmetry of lasing process is obtained with the destructive interference at the cavity interfaces. The frequency range of CPA is generally dependent on the decay rates of the cavity mirrors. The smaller decay rate of the cavity mirror causes the wider frequency range of CPA, and the needed intensity of the probe fields is larger to satisfy CPA condition for a given frequency. Although Rabi frequency of the control laser has little effect on the frequency range of CPA, with EIT-type quantum interference, the CPA mode is tunable by the control laser. In addition, with the relative phase, the probe fields can be perfectly transmitted and/or reflected. Therefore, the system can be used as a controllable coherent perfect absorber or transmitter (reflector), and our work may have practical applications in optical logic devices.
Polarization conversion in anisotropic dielectric metasurfaces originating from bound states in the continuum
Authors: Chen Xiaolin , Zhou Yong , Ma Xiaohui , Fang Wentan , Zhang Wei , Gao Weiqing
Published: July 2021

We use the semianalytical Cartesian multipole method to investigate the light transmission and reflection spectra of anisotropic dielectric metasurfaces, and extend the multipole decompositions method to account for cross-polarization conversion effects. We observe sharp high-

Q

resonances arising from a distortion of symmetry-protected bound states in the continuum in asymmetric dielectric metasurfaces, i.e., quasibound states in the continuum. In addition, by further introducing in-plane symmetric breaking perturbation, the polarization conversions of linearly polarized light can be achieved through quasibound states in the continuum. With the aid of temporal coupled-mode theory, we can obtain the limit of cross-conversion under single high-

Q

resonance, i.e., 0.25. Our work will help to design dielectric metasurfaces to control the polarization states of light.
Circularly polarized optical microscope using a low aberration liquid crystal lens
Authors: Chen Wei-Wei , Pan Jui-Wen , Jeng Shie-Chang
Published: July 2021

We demonstrate a circularly polarized optical microscope (POM) by incorporating a hole-patterned electrode (HPE) liquid crystal (LC) lens fabricated by photoalignment. The focal plane is controlled by voltages on the HPE LC lens with a tuning range of 2.2 mm without any mechanical movement. The diopter can be controlled from 0 to

−

5.0

D

, and the wavefront optical path difference is less than

0.25

λ

for our proposed HPE LC lens. Such a low aberration is obtained, because the LC directors are well aligned along with the axially symmetrical electrical field, and there is no observed twist deformation of the LC directors. Finally, we applied our circularly polarized POM to inspect the reflectance properties of several beetles, and we find that the “Chrysochroa toulgoeti” beetle exhibits right circularly polarized reflectance from some small areas on its wings.
High-performance 4096× ultra-high CPV module based on multiple concentrator units and optical guides
Authors: Ceballos María A. , Fernández Eduardo F. , Rodrigo Pedro M. , Valera Álvaro , Pérez-higueras Pedro J. , Almonacid Florencia
Published: July 2021

Ultra-high concentrator photovoltaic systems aim to enhance the conversion efficiency of sunlight and to reduce the cost of electricity. However, it is still necessary to develop optical systems with higher efficiencies and angular tolerances for them to become a reality. This Letter proposes a novel design that is able to achieve a geometric concentration of

4096

×

. The system consists of four concentrator units based on parabolic mirrors and optical guides that concentrate the sunlight onto a single cell. Additionally, a preliminary proof-of-concept module has been assembled for validation purposes. The novel design exceeds the optical efficiency of the existing systems,

≈

84

%

, and offers almost double acceptance angles,

≈

0.6

∘

.
Square-root topological state of coupled plasmonic nanoparticles in a decorated Su–Schrieffer–Heeger lattice
Authors: Wu Huizhou , Wei Guochao , Liu Zhenzhen , Xiao Jun-Jun
Published: July 2021

The square-root operation can generate systems with new (to the best of our knowledge) topological phases whose topological properties are inherited from the parent Hamiltonian. In this Letter, we introduce the concept of square-root topology in the two-dimensional (2D) Su–Schrieffer–Heeger (SSH) model and construct a square-root topological square nanoparticle lattice (SRTL) by inserting additional sites into the original 2D SSH model. We find that the topological states in the SRTL are intriguingly different from those in the corresponding SSH model (with on-site potential) due to the change in symmetrical characteristics. Plasmonic nanoparticle arrays are used to demonstrate this by including both nearest-neighbor and next-nearest-neighbor interactions within the dipole approximation. These unique topological states, such as the single corner mode and multiple topological edge modes, enrich the topological features produced by square-root operation and expand the scope to apply such topological features into photonic systems.
Non-Hermitian photonics for coherent perfect absorbtion, invisibility, and lasing with different orbital angular momenta: publisher’s note
Authors: Bai Ping , Luo Jie , Chu Hongchen , Lu Weixin , Lai Yun
Published: July 2021

This publisher’s note contains a correction to Opt. Lett. 45, 6635 (2020)OPLEDP0146-959210.1364/OL.409690.
Gate-free integrated-optic tunable filter for demultiplexing various capacity optical OFDM signals
Authors: Takiguchi Koichi , Masaki Hideaki
Published: July 2021

Spectrally efficient optical communication with flexible capacity is required in the prospective adaptive photonic network. Optical orthogonal frequency division multiplexing (OFDM) is one of candidates to contribute to this type of photonic network. Here we report on a gate-free integrated-optic tunable filter that can demultiplex optical OFDM signals with various number and symbol rate sub-carrier channels. The filter consists of tunable couplers, an array of delay lines, and a slab star coupler-type optical Fourier transformation circuit. We can tune the number and/or the symbol rate of demultiplexed optical OFDM channels by selecting the delay lines with the tunable couplers. Optical timing gates were normally attached to the filter output ports with a view to extracting the effective time of the filtered channels. In this investigation, we removed the optical gates and substituted a high-speed photodetector for the gate with a view to achieving completely passive demultiplexing of the various capacity optical OFDM signals. Various channel symbol rate and channel number OFDM signals (5 × 10 to 20 Gsymbol/s and 3 × 20 Gsymbol/s) were successfully demultiplexed with this gate-free tunable filter. Our star coupler-type tunable OFDM filter without the gates was used to demultiplex various channel symbol rate optical OFDM signals for the first time.
500  μm field-of-view probe-based confocal microendoscope for large-area visualization in the gastrointestinal tract
Authors: Li Hua , Hao Zhengyi , Huang Jiangfeng , Lu Tingting , Liu Qian , Fu Ling
Published: July 2021

Rapid large-area tissue imaging at the cellular resolution is important for clinical diagnosis. We present a probe-based confocal microendoscope (pCM) with a field-of-view (FOV) diameter over 500 μm, lateral resolution of 1.95 μm, and outer diameter of 2.6 mm, compatible with the biopsy channel of conventional gastroscopes. Compared to a conventional pCM, our system’s FOV increased by a factor of 4 while maintaining the probe size and cellular resolution—comparable to the FOV of Zeiss Axio Observer’s

20
×
/
0.8

numerical aperture objective lens. Ex vivo imaging of wide areas in healthy and diseased rat gastrointestinal tract tissues demonstrates the system’s practicality.
Fission yeast Rad8/HLTF facilitates Rad52-dependent chromosomal rearrangements through PCNA lysine 107 ubiquitination
Authors: Su Jie , Xu Ran , Mongia Piyusha , Toyofuku Naoko , Nakagawa Takuro
Published: July 2021

Gross chromosomal rearrangements (GCRs), including translocation, deletion, and inversion, can cause cell death and genetic diseases such as cancer in multicellular organisms. Rad51, a DNA strand exchange protein, suppresses GCRs by repairing spontaneous DNA damage through a conservative way of homologous recombination, gene conversion. On the other hand, Rad52 that catalyzes single-strand annealing (SSA) causes GCRs using homologous sequences. However, the detailed mechanism of Rad52-dependent GCRs remains unclear. Here, we provide genetic evidence that fission yeast Rad8/HLTF facilitates Rad52-dependent GCRs through the ubiquitination of lysine 107 (K107) of PCNA, a DNA sliding clamp. Inrad51Δcells, loss of Rad8 eliminated 75% of the isochromosomes resulting from centromere inverted repeat recombination, showing that Rad8 is essential for the formation of the majority of isochromosomes inrad51Δcells. Rad8 HIRAN and RING finger mutations reduced GCRs, suggesting that Rad8 facilitates GCRs through 3’ DNA-end binding and ubiquitin ligase activity. Mms2 and Ubc4 but not Ubc13 ubiquitin-conjugating enzymes were required for GCRs. Consistent with this, mutating PCNA K107 rather than the well-studied PCNA K164 reduced GCRs. Rad8-dependent PCNA K107 ubiquitination facilitates Rad52-dependent GCRs, as PCNA K107R,rad8, andrad52mutations epistatically reduced GCRs. In contrast to GCRs, PCNA K107R did not significantly change gene conversion rates, suggesting a specific role of PCNA K107 ubiquitination in GCRs. PCNA K107R enhanced temperature-sensitive growth defects of DNA ligase Icdc17-K42mutant, implying that PCNA K107 ubiquitination occurs when Okazaki fragment maturation fails. Remarkably, K107 is located at the interface between PCNA subunits, and an interface mutation D150E bypassed the requirement of PCNA K107 and Rad8 ubiquitin ligase for GCRs. These data suggest that Rad8-dependent PCNA K107 ubiquitination facilitates Rad52-dependent GCRs by changing the PCNA clamp structure.
Induction of a chromatin boundary in vivo upon insertion of a TAD border
Authors: Willemin Andréa , Lopez-Delisle Lucille , Bolt Christopher Chase , Gadolini Marie-Laure , Duboule Denis , Rodriguez-Carballo Eddie
Published: July 2021

Mammalian genomes are partitioned into sub-megabase to megabase-sized units of preferential interactions called topologically associating domains or TADs, which are likely important for the proper implementation of gene regulatory processes. These domains provide structural scaffolds for distant cis regulatory elements to interact with their target genes within the three-dimensional nuclear space and architectural proteins such as CTCF as well as the cohesin complex participate in the formation of the boundaries between them. However, the importance of the genomic context in providing a given DNA sequence the capacity to act as a boundary element remains to be fully investigated. To address this question, we randomly relocated a topological boundary functionally associated with the mouse HoxD gene cluster and show that it can indeed act similarly outside its initial genomic context. In particular, the relocated DNA segment recruited the required architectural proteins and induced a significant depletion of contacts between genomic regions located across the integration site. The host chromatin landscape was re-organized, with the splitting of the TAD wherein the boundary had integrated. These results provide evidence that topological boundaries can function independently of their site of origin, under physiological conditions during mouse development.
A review of the leishmanin skin test: A neglected test for a neglected disease
Authors: Carstens-Kass Jessica , Paulini Kayla , Lypaczewski Patrick , Matlashewski Greg
Published: July 2021

The leishmanin skin test (LST) has been used for decades to detect exposure and immunity to the parasiteLeishmania, the causative agent of the neglected tropical disease leishmaniasis. In the LST,Leishmaniaantigen (leishmanin) is intradermally injected into the forearm. In an individual who has been previously infected, a delayed-type hypersensitivity (DTH) reaction results in a measurable induration at the site of the injection, indicating that previous exposure toLeishmaniahas resulted in the development of cell-mediated immunity. LST positivity is associated with long-lasting protective immunity against reinfection, most notably as reported for visceral leishmaniasis (VL). Despite efforts over the past few decades, leishmanin antigen is no longer produced under good manufacturing practice (GMP) conditions anywhere in the world. Consequently, the use of the LST in epidemiological studies has declined in favor of serological and molecular tests. In this review, we provide a historical overview of the LST and justification for the reintroduction of leishmanin. A GMP-grade leishmanin can be used to detect immunity in vivo by the LST and can be investigated for use in an interferon-γ release assay (IGRA), which may serve as an in vitro version of the LST. The LST will be a valuable tool for surveillance and epidemiological studies in support of the VL elimination programs and as a surrogate marker of immunity in vaccine clinical trials.

Methods

A review of the literature was conducted using PubMed as the primary database, with MeSH terms “leishmanin skin test” OR “Montenegro test” OR “Montenegro skin test.” Articles written in English that describe the history or standardization of leishmanin, the use of leishmanin in an IGRA, or the use of the LST in epidemiological studies or vaccine trials were prioritized in our appraisal of the literature.
The effects of Cstb duplication on APP/amyloid-β pathology and cathepsin B activity in a mouse model
Authors: Wu Yixing , Whittaker Heather T. , Noy Suzanna , Cleverley Karen , Brault Veronique , Herault Yann , Fisher Elizabeth M. C. , Wiseman Frances K.
Published: July 2021

People with Down syndrome (DS), caused by trisomy of chromosome 21 have a greatly increased risk of developing Alzheimer’s disease (AD). This is in part because of triplication of a chromosome 21 gene, APP. This gene encodes amyloid precursor protein, which is cleaved to form amyloid-β that accumulates in the brains of people who have AD. Recent experimental results demonstrate that a gene or genes on chromosome 21, other than APP, when triplicated significantly accelerate amyloid-β pathology in a transgenic mouse model of amyloid-β deposition. Multiple lines of evidence indicate that cysteine cathepsin activity influences APP cleavage and amyloid-β accumulation. Located on human chromosome 21 (Hsa21) is an endogenous inhibitor of cathepsin proteases, CYSTATIN B (CSTB) which is proposed to regulate cysteine cathepsin activity in vivo. Here we determined if three copies of the mouse gene Cstb is sufficient to modulate amyloid-β accumulation and cathepsin activity in a transgenic APP mouse model. Duplication of Cstb resulted in an increase in transcriptional and translational levels of Cstb in the mouse cortex but had no effect on the deposition of insoluble amyloid-β plaques or the levels of soluble or insoluble amyloid-β42, amyloid-β40, or amyloid-β38 in 6-month old mice. In addition, the increased CSTB did not alter the activity of cathepsin B enzyme in the cortex of 3-month or 6-month old mice. These results indicate that the single-gene duplication of Cstb is insufficient to elicit a disease-modifying phenotype in the dupCstb x tgAPP mice, underscoring the complexity of the genetic basis of AD-DS and the importance of multiple gene interactions in disease.
Genome-wide survey of the F-box/Kelch (FBK) members and molecular identification of a novel FBK gene TaAFR in wheat
Authors: Wei Chunru , Zhao Weiquan , Fan Runqiao , Meng Yuyu , Yang Yiming , Wang Xiaodong , Foroud Nora A. , Liu Daqun , Yu Xiumei
Published: July 2021

F-box proteins play critical roles in plant responses to biotic/abiotic stresses. In the present study, a total of 68 wheat F-box/Kelch (TaFBK) genes, unevenly distributed across 21 chromosomes and encoding 74 proteins, were identified in EnsemblPlants. Protein sequences were compared with those of Arabidopsis and three cereal species by phylogenetic and domain analyses, where the wheat sequences were resolved into 6 clades. In silico analysis of a digital PCR dataset revealed that TaFBKs were expressed at multiple developmental stages and tissues, and in response to drought and/or heat stresses. The TaFBK19 gene, a homolog of the Attenuated Far-Red Response (AFR) genes in other plant species, and hence named TaAFR, was selected for further analysis. Reverse-transcription quantitative real-time PCR (RT-qPCR) was carried out to determine tissue-specific, hormone and stress (abiotic/biotic) responsive expression patterns. Of interest, TaAFR was expressed most abundantly in the leaves, and its expression in response to leaf rust variants suggests a potential role in compatible vs incompatible rust responses. The protein was predicted to localize in cytosol, but it was shown experimentally to localize in both the cytosol and the nucleus of tobacco. A series of protein interaction studies, starting with a yeast-2-hybrid (Y2H) library screen (wheat leaf infected with incompatible leaf rust pathogens), led to the identification of three TaAFR interacting proteins. Skp1/ASK1-like protein (Skp1) was found to interact with the F-box domain of TaAFR, while ADP-ribosylation factor 2-like isoform X1 (ARL2) and phenylalanine ammonia-lyase (PAL) were shown to interact with its Kelch domain. The data presented herein provides a solid foundation from which the function and metabolic network of TaAFR and other wheat FBKs can be further explored.
Spatially resolved analysis of Pseudomonas aeruginosa biofilm proteomes measured by laser ablation sample transfer
Authors: Pulukkody Aruni Chathurya , Yung Yeni P. , Donnarumma Fabrizio , Murray Kermit K. , Carlson Ross P. , Hanley Luke
Published: July 2021

Heterogeneity in the distribution of nutrients and oxygen gradients during biofilm growth gives rise to changes in phenotype. There has been long term interest in identifying spatial differences during biofilm development including clues that identify chemical heterogeneity. Laser ablation sample transfer (LAST) allows site-specific sampling combined with label free proteomics to distinguish radially and axially resolved proteomes for Pseudomonas aeruginosa biofilms. Specifically, differential protein abundances on oxic vs. anoxic regions of a biofilm were observed by combining LAST with bottom up proteomics. This study reveals a more active metabolism in the anoxic region of the biofilm with respect to the oxic region for this clinical strain of P. aeruginosa, despite this organism being considered an aerobe by nature. Protein abundance data related to cellular acclimations to chemical gradients include identification of glucose catabolizing proteins, high abundance of proteins from arginine and polyamine metabolism, and proteins that could also support virulence and environmental stress mediation in the anoxic region. Finally, the LAST methodology requires only a few mm2 of biofilm area to identify hundreds of proteins.
Ending the HIV epidemic using National HIV Behavioral Surveillance (NHBS): Recommendations based on DC model
Authors: Das Suparna , Medina Richard , Nicolosi Emily , Agopian Anya , Kuo Irene , Opoku Jenevieve , Allston Adam , Kharfen Michael
Published: July 2021

Introduction

Social network strategies have been used by health departments to identify undiagnosed cases of HIV. Heterosexual cycle (HET4) of National HIV Behavioral Surveillance (NHBS) is a social network strategy implemented in jurisdictions. The main objectives of this research are to 1) evaluate the utility of the NHBS HET cycle data for network analysis; 2) to apply statistical analysis in support of previous HIV research, as well as to develop new research results focused on demographic variables and prevention/intervention with respect to heterosexual HIV risk; and 3) to employ NHBS data to inform policy with respect to the EHE plan.

Method

We used data from the 2016 NHBS HET4 (DC). A total of 747 surveys were collected. We used the free social-network analysis package, GEPHI, for all network visualization using adjacency matrix representation. We additionally conducted logistic regression analysis to examine the association of selected variables with HIV status in three models representing 1) demographic and economic effects, 2) behavioral effects, and 3) prevention-intervention effects.

Results

The results showed 3% were tested positive. Seed 1 initiated the largest networks with 426 nodes (15 positives); seed 4 with 273 nodes (6 positives). Seed 3 had 35 nodes (2 positives). All 23 HIV diagnoses were recruited from 4 zip-codes across DC. The risk of testing positive was higher among people high-school dropouts (Relative Risk (RR) (25.645); 95 CI% 5.699, 115.987), unemployed ((4.267); 1.295, 14.064), returning citizens ((14.319); 4.593, 44.645). We also found in the final model higher association of pre-exposure prophylaxis (PrEP) awareness among those tested negative ((4.783); 1.042, 21.944) and HIV intervention in the past 12 months with those tested positive ((17.887); 2.350,136.135).

Conclusion

The network visualization was used to address the primary aim of the analysis-evaluate the success of the implementation of the NHBS as a social network strategy to find new diagnoses. NHBS remains one of the strongest behavioral supplements for DC’s HIV planning activities. As part of the evaluation process our analysis helps to understand the impact of demographic, behavioral, and prevention efforts on peoples’ HIV status. We strongly recommend other jurisdictions use network visualizations to evaluate the efficacy in reaching hidden populations.
The influence of propofol-based total intravenous anesthesia on postoperative outcomes in end-stage renal disease patients: A retrospective observation study
Authors: Cho Ho Bum , Kim Mun Gyu , Park Sun Young , Song Sanghoon , Jang Youn Sil , Park Suyeon , Lee Hyun Keun , Yoo Jae Hwa , Chung Ji Won , Kim Sang Ho
Published: July 2021

Background

To determine whether the anesthetic method of propofol total intravenous anesthesia (TIVA) is associated with postoperative outcome in ESRD patients, we evaluated the incidence of postoperative major adverse cardiac events (MACE), comparing propofol TIVA versus anesthesia with volatile anesthesia in ESRD patients.

Methods

Retrospectively, we identified cases with ESRD patients who underwent surgery under general anesthesia. Patients were divided into those who received only volatile anesthesia (volatile group) and those who received only propofol TIVA (TIVA group). The incidence of MACE and potential confounding variables were compared separately in a univariate logistic model and subsequently by multivariate logistic regression.

Results

Among the 2576 cases in ESRD patients, 1374 were in the TIVA group and 1202 were in the volatile group. The multivariate analysis included 12 factors, including the anesthesia method, of which five factors were significant. Factors that were associated with a significantly lower MACE risk included preoperative chloride concentration (OR: 0.96; 95% CI, 0.92–0.99), baseline SBP (OR: 0.98; 95% CI, 0.98–0.99), and propofol TIVA (OR: 0.37; 95% CI, 0.22–0.60).

Conclusions

We inferred that the anesthetic method associated with the postoperative outcome in patients with ESRD.
Divergent long-term impacts of lethally toxic cane toads (Rhinella marina) on two species of apex predators (monitor lizards, Varanus spp.)
Authors: Pettit Lachlan , Crowther Mathew S. , Ward-Fear Georgia , Shine Richard
Published: July 2021

Biological invasions can massively disrupt ecosystems, but evolutionary and ecological adjustments may modify the magnitude of that impact through time. Such post-colonisation shifts can change priorities for management. We quantified the abundance of two species of giant monitor lizards, and of the availability of their mammalian prey, across 45 sites distributed across the entire invasion trajectory of the cane toad (Rhinella marina) in Australia. One varanid species (Varanus panoptes from tropical Australia) showed dramatic population collapse with toad invasion, with no sign of recovery at most (but not all) sites that toads had occupied for up to 80 years. In contrast, abundance of the other species (Varanus varius from eastern-coastal Australia) was largely unaffected by toad invasion. That difference might reflect availability of alternative food sources in eastern-coastal areas, perhaps exacerbated by the widespread prior collapse of populations of small mammals across tropical (but not eastern) Australia. According to this hypothesis, the impact of cane toads on apex predators has been exacerbated and prolonged by a scarcity of alternative prey. More generally, multiple anthropogenically-induced changes to natural ecosystems may have synergistic effects, intensifying the impacts beyond that expected from either threat in isolation.