bluuebunny/crossref_metadata_2025 huggingface dataset:
SARS-CoV-2 and the role of fomite transmission: a systematic review
Authors: Onakpoya Igho J. , Heneghan Carl J. , Spencer Elizabeth A. , Brassey Jon , Plüddemann Annette , Evans David H. , Conly John M. , Jefferson Tom
Published: May 2021

Background:SARS-CoV-2 RNA has been detected in fomites which suggests the virus could be transmitted via inanimate objects. However, there is uncertainty about the mechanistic pathway for such transmissions. Our objective was to identify, appraise and summarise the evidence from primary studies and systematic reviews assessing the role of fomites in transmission. 

Methods:This review is part of an Open Evidence Review on Transmission Dynamics of SARS-CoV-2. We conduct ongoing searches using WHO Covid-19 Database, LitCovid, medRxiv, and Google Scholar; assess study quality based on five criteria and report important findings on an ongoing basis.

Results:We found 64 studies: 63 primary studies and one systematic review (n=35). The settings for primary studies were predominantly in hospitals (69.8%) including general wards, ICU and SARS-CoV-2 isolation wards. There were variations in the study designs including timing of sample collection, hygiene procedures, ventilation settings and cycle threshold. The overall quality of reporting was low to moderate. The frequency of positive SARS-CoV-2 tests across 51 studies (using RT-PCR) ranged from 0.5% to 75%. Cycle threshold values ranged from 20.8 to 44.1. Viral concentrations were reported in 17 studies; however, discrepancies in the methods for estimation prevented comparison. Eleven studies (17.5%) attempted viral culture, but none found a cytopathic effect. Results of the systematic review showed that healthcare settings were most frequently tested (25/35, 71.4%), but laboratories reported the highest frequency of contaminated surfaces (20.5%, 17/83). 

Conclusions:The majority of studies report identification of SARS-CoV-2 RNA on inanimate surfaces; however, there is a lack of evidence demonstrating the recovery of viable virus. Lack of positive viral cultures suggests that the risk of transmission of SARS-CoV-2 through fomites is low. Heterogeneity in study designs and methodology prevents comparisons of findings across studies. Standardized guidelines for conducting and reporting research on fomite transmission is warranted.
Health-Related Quality Of Life, Uncertainty, ‎and Anxiety among Patients with Chronic Obstructive Pulmonary Disease
Authors: Abu Tabar Nazih , Al Qadire Mohammad , Thultheen Imad , Alshraideh Jafar
Published: May 2021

Patients’ with Chronic Obstructive Pulmonary Disease suffer from serious respiratory symptoms that increase anxiety, stress, and uncertainty, and affect quality of life. The aim of this study was to assess level of anxiety, uncertainty, and health related quality of life (HRQoL) among COPD patients in Jordan. Correlational cross-sectional survey design was used to collect data from 153 COPD patients. ‎The study was conducted at pulmonary clinics in three major referral hospitals in Jordan that provide care for COPD patients from different parts of the country. To assess HRQoL, St. George ‎Respiratory Questionnaire‎ was completed. Uncertainty and anxiety level was measured by Mishel's uncertainty of illness scale and state anxiety inventory respectively. The mean age of participants was 66.8 (SD= 10.3) and most participants were males (94.1%) with. The mean score of HRQoL was 57.9 (SD = 20.5). The mean score of participants’ level of anxiety was 38.1 (SD = 11.1). The mean score of uncertainty was 66.1 (SD= 11.1). There is a statistically significant positive relationship between HRQoL and anxiety (r =.433, p< .01), and uncertainty (r=.483, p<.01). Increased anxiety and uncertainty among COPD patients was associated with low HRQoL. Health care providers need to pay attention the effect of anxiety and uncertainty on COPD patients’ quality of life and institute appropriate management.
Building long-term vision for rural areas through multi-actor platforms: a preliminary study in the Emilia-Romagna region
Authors: Pellegrini Emilia , Raggi Meri , Viaggi Davide , Targetti Stefano
Published: May 2021

Developing long-term visions through participatory approaches can be very useful to explore different possible scenarios and pathways to reach desirable futures. This brief report describes a participatory process carried out in the Emilia-Romagna region (Italy) to develop a long-term vision for rural areas by 2040. This approach consisted of: (i) interviews and a focus group carried out with a multi-actor platform (MAP) composed of experts from science-society-policy sectors, and (ii) an on-line questionnaire addressing a larger number of rural stakeholders of the region. Mixing expert-based consultation through the MAP with a more inclusive consultation approach resulted in an effective method to build long-term visions in the very heterogeneous rural context of the Emilia-Romagna. However, this study only constitutes a preliminary step into a more elaborated backcasting approach.
Molecular characterization of Plasmodium falciparum PHISTb proteins as potential targets of naturally-acquired immunity against malaria
Authors: Isebe Tony I. , Bargul Joel L. , Gichuki Bonface M. , Njunge James M. , Tuju James , Rono Martin K.
Published: May 2021

Background: Plasmodium falciparum causes the deadliest form of malaria in humans. Upon infection, the host’s infected red blood cells (iRBCs) are remodelled by exported parasite proteins to provide a niche for parasite development and maturation.

Methods: Here we analysed the role of three PHISTb proteins Pf3D7_0532400, Pf3D7_1401600, and Pf3D7_1102500 by expressing recombinant proteins and evaluated antibody responses against these proteins using immune sera from malaria-exposed individuals from Kenya and The Gambia in Africa.

Results: Children and adults from malaria-endemic regions recognized the three PHISTb proteins. Responses against PHISTb proteins varied with malaria transmission intensity in three different geographical sites in Kenya (Siaya and Takaungu) and The Gambia (Sukuta). Antibody responses against PHISTb antigens Pf3D7_1102500 and Pf3D7_1401600 were higher in Sukuta, a low transmission region in Gambia, compared to Siaya, a high transmission region in western Kenya, unlike Pf3D7_0532400. Anti-PHIST responses indicate negative correlation between antibody levels and malaria transmission intensity for Pf3D7_1102500 and Pf3D7_1401600. We report a correlation in antibody responses between schizont and gametocyte extract, but this is not statistically significant (cor=0.102, p=0.2851, CI=95%) and, Pf3D7_0532400 (cor=0.11, p=0.249, CI=95%) and Pf3D7_1401600 (cor=0.02, p=0.7968, CI=95%). We report a negative correlation in antibody responses between schizont and Pf3D7_1102500 (cor=-0.008, p=0.9348, CI=95%). There is a correlation between gametocyte extract and Pf3D7_1401600 (cor=-0.0402, p=0.6735, CI=95%), Pf3D7_1102500 (cor=0.0758, p=0.4271, CI=95%) and Pf3D7_0532400 (cor=0.155, p=0.1028, CI=95%). Acquisition of anti-PHIST antibodies correlates with exposure to malaria for Pf3D7_0532400 (p=0.009) but not Pf3D7_1102500 and Pf3D7_1401600 (p=0.507 and p=0.15, respectively, CI=95%). Children aged below 2 years had the lowest antibody levels which do not correlate with age differences.

Conclusions: Collectively, these findings provide evidence of natural immunity against PHISTb antigens that varies with level of malaria exposure and underscore their potential as possible serological markers to P. falciparum infection aimed at contributing to malaria control through vaccine development.
‘Capacity for what? Capacity for whom?’ A decolonial deconstruction of research capacity development practices in the Global South and a proposal for a value-centred approach
Authors: Mormina Maru , Istratii Romina
Published: May 2021

Whilst North to South knowledge transfer patterns have been extensively problematised by Southern and decolonial perspectives, there is very little reflection on the practice of research capacity development (RCD), still strongly focused on technoscientific solutionism, yet largely uncritical of its underlying normative directions and power asymmetries. Without making transparent these normative and epistemological dimensions, RCD practices will continue to perpetuate approaches that are likely to be narrow, technocratic and unreflexive of colonial legacies, thus failing to achieve the aims of RCD, namely, the equitable and development-oriented production of knowledge in low- and middle-income societies. Informed by the authors’ direct experience of RCD approaches and combining insights from decolonial works and other perspectives from the margins with Science and Technology Studies, the paper undertakes a normative and epistemological deconstruction of RCD mainstream practice. Highlighting asymmetries of power and material resources in knowledge production, the paper’s decolonial lens seeks to aid the planning, implementation and evaluation of RCD interventions. Principles of cognitive justice and epistemic pluralism, accessibility enabled by systems thinking and sustainability grounded on localisation are suggested as the building blocks for more reflexive and equitable policies that promote research capacityforthe purpose of creating social value and not solely for the sake of perpetuating technoscience.
Radiation Contribution Assessment to Development of Multiple Oncological Diseases in the Late Period of Acute Radiation Disease
Authors: Galstyan I. , Konchalovsky M. , Kozlova M. , Nugis V.
Published: May 2021

Purpose: On clinical examples to estimate a probable contribution of the postponed earlier external radiation of all body in the doses exceeding 1 Gy at development of multiple malignant neoplasms of different localization and a leukaemia.

Material and methods: At 8 of 164 patients, it is long observed after the postponed acute radiation syndrome (ARS), multiple oncological diseases are revealed. Dynamics of consecutive forming of solid tumors at 2 patients and also malignant neoplasms and a myelodysplastic syndrome (MDS) with transformation in an acute leukamia at 1 patient is tracked. Observation duration – 31 years, 43 years and 32 years.

Results: Availability of medical care to the patients who transferred ARS and high quality of its rendering at all stages (out-patient, stationary) allowed to reveal malignant neoplasms at early stages of development and to achieve an absolute recovery. However eventually at these patients development and other oncological diseases was observed. The given clinical observations allow to assume that at presented cases radiation acted on various stages of carcinogenesis, and its contribution to development of different oncological diseases in all patients was not identical.

Conclusion: The analysis of clinical observations allows to assume that radiation contribution to genesis of various oncological diseases at the persons which underwent radiation in the doses causing development of ARS is various. Now in our country there are no approaches to quantitative assessment of a contribution of radiation effects to development of malignant neoplasms in each case. The patients who underwent acute single exposition in doses over 1 Gy have to be considered as having predisposition to development of multiple tumors in the remote terms. In this regard they for life need medical follow up for the purpose of early diagnostics and adequate treatment of the developing malignant neoplasms.
Free Vascularized Medial Femoral Condyle Bone Graft for Scaphoid Nonunion with Poor Prognosis Factors
Authors: Park Sam-Guk , Shim Bum-Jin , Seok Hyun-Gyu
Published: May 2021

Purpose: Authors attempt to evaluate the clinical and radiographic results of the treatment of scaphoid nonunion with poor prognostic factors with the free vascularized medial femoral condyle bone graft. Methods: We operated on eight patients with avascular necrosis or prolonged nonunion of the scaphoid between January 2016 and July 2019. Wrist motion in terms of flexion, extension, and ulnar and radial deviation, a visual analogue scale (VAS), the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, the modified Mayo wrist score, scapholunate angle, and carpal height index were collected in the clinic setting preoperatively and at the latest follow-up in all patients Results: Eight patients with union achieved correction and maintenance of both scapholunate angle and carpal height index. The VAS pain scores significantly improved from 5.1 preoperatively to 3.3 postoperatively. There was a statistically significant improvement in the average DASH score at the final follow-up. Scapholunate relationships in the reconstructed wrists remained almost unchanged, with average scapholunate angles of 49.7° before surgery and 47.0° at the latest postoperative follow-up. There was no statistical significance between the number of poor prognosis factors and the time to union, but there was a positive correlation.Conclusion: It could help surgeons manage the scaphoid nonunion associated with poor prognostic factors such as avascular necrosis, carpal collapse (posttraumatic arthritis), prolonged nonunion, and failed prior scaphoid nonunion surgery.
Demonstration of high-efficiency photonic lantern couplers for PolyOculus
Authors: Moraitis Christina D. , Alvarado-Zacarias Juan Carlos , Amezcua-Correa Rodrigo , Jeram Sarik , Eikenberry Stephen S.
Published: May 2021

The PolyOculus technology produces large-area-equivalent telescopes by
using fiber optics to link modules of multiple semi-autonomous, small,
inexpensive, commercial-off-the-shelf telescopes. Crucially, this
scalable design has construction costs that are

>

10
×

lower than equivalent traditional
large-area telescopes. We have developed a novel, to the best of our
knowledge, photonic lantern approach for the PolyOculus fiber optic
linkages that potentially offers substantial advantages over
previously considered free-space optical linkages, including much
higher coupling efficiencies. We have carried out the first laboratory
tests of a photonic lantern prototype developed for PolyOculus, and
demonstrated broadband efficiencies of

∼

91
%

, confirming the outstanding
performance of this technology.
Spectroradiometer spectral calibration, ISRF shapes, and related uncertainties
Authors: Trim Simon A. , Mason Kimberley , Hueni Andreas
Published: May 2021

A key characteristic of a spectroradiometer is the instrumental
spectral response function (ISRF) that is determined during spectral
characterization and calibration. The response shape of the ISRF is
commonly assumed to be Gaussian, though this is known to not always be
the best description. We show that in the context of laboratory
calibration, the largest source of uncertainty lies in the ISRF
assumption. We perform the spectral calibration of laboratory
measurements obtained with four analytical spectral device field
spectroradiometers using several different ISRF “modes” to investigate
their respective fitting performance, and examine the impact of
choosing an ISRF that differs from a Gaussian when calibrating a
MODTRAN6 spectrum. Finally, we conduct the uncertainty analysis of our
calibration by propagating uncertainty via a Monte Carlo method.
Theoretically comparative study of spectrally selective solar absorbers
in concentrated solar-thermoelectric generators working at high
temperature
Authors: Tapsanit Piyawath
Published: May 2021

A spectrally selective solar absorber (SSA) made from alternating tungsten and

S
i
O

2

layers is an important component in a
concentrated solar-thermoelectric generator (CSTEG). However, the
highly efficient SSA consisting of a high number of tungsten and

S
i
O

2

layers may require complicated
fabrication procedures, thereby raising the overall cost of the CSTEG.
In this study, we have theoretically optimized SSAs consisting of a
different number of layers, and the performances of CSTEGs installed
with different optimized SSAs and thermoelectric materials (

S
i

80

G
e

20

alloys, SnSe crystals) are
theoretically investigated. It is found that two SSAs, one with only
one layer of

S
i
O

2

glass (88 nm) coated on a tungsten
reflective plane, and the other with three alternating layers of

S
i
O

2

(

92

n
m

)

/

t
u
n
g
s
t
e
n

(

7

n
m

)

/

S
i
O

2

(

78

n
m

)

coated on a tungsten reflective
plane, have the highest average solar absorptance equal to 0.7050 and
0.9999, respectively. To reach the same steady-state temperature (

T
h

), the one-layer SSA requires higher
optical concentrations (

C

o
p
t

) than the three-layer SSA. The CSTEG
with

S
i

80

G
e

20

alloys requires much higher optical

C

o
p
t

than the CSTEG with SnSe crystals in
order to reach the same

T
h

because of much a higher rate of heat
flux. At

T
h

=

800

deg
⁡

C

, the CSTEG with

S
i

80

G
e

20

alloys have the output electrical
power per unit cross-sectional area of TEG about 6 times higher than
that of the CSTEG with SnSe crystals. The net efficiency of CSTEG with
SnSe crystals could reach 25.6% if the electrical conductivity of its
p-type thermoelectric leg could be enhanced to be comparable to the
electrical conductivity of its n-type thermoelectric leg.
Simulation of anisoplanatic lucky look imaging and statistics through optical turbulence using numerical wave propagation
Authors: Rucci Michael A. , Hardie Russell C. , Martin Richard K.
Published: May 2021

This paper investigates anisoplanatic numerical wave simulation in the
context of lucky look imaging. We demonstrate that numerical wave
propagation can produce root mean square (RMS) wavefront distributions
and probability of lucky look (PLL) statistics that are consistent
with Kolmogorov theory. However, the simulated RMS statistics are
sensitive to the sampling parameters used in the propagation window.
To address this, we propose and validate a new sample spacing rule
based on the point source bandwidth used in the propagation and the
level of atmospheric turbulence. We use the tuned simulator to
parameterize the wavefront RMS probability density function as a
function of turbulence strength. The fully parameterized RMS
distribution model is used to provide a way to accurately predict the
PLL for a range of turbulence strengths. We also propose and validate
a new parametric average lucky look optical transfer function (OTF)
model that could be used to aid in image restoration. Our OTF model
blends the theoretical diffraction-limited OTF and the average
turbulence short exposure OTF. Finally, we show simulated images for
several anisoplanatic imaging scenarios that reveal the spatially
varying nature of the RMS values impacting local image quality.
C+L-band upgrade strategies to sustain traffic growth in optical backbone networks
Authors: Ahmed Tanjila , Mitra Abhijit , Rahman Sabidur , Tornatore Massimo , Lord Andrew , Mukherjee Biswanath
Published: May 2021

We investigate cost-efficient upgrade strategies for capacity
enhancement in optical backbone networks enabled by C+L-band optical
line systems. A multi-period strategy for upgrading network links from
the C band to the C+L band is proposed, ensuring physical-layer
awareness, cost effectiveness, and less than 0.1% blocking. Results
indicate that the performance of an upgrade strategy depends on
efficient selection of the sequence of links to be upgraded and on the
time instant to upgrade, which are either topology or traffic
dependent. Given a network topology, a set of traffic demands, and
growth projections, our illustrative numerical results show that a
well-devised upgrade strategy can achieve superior cost efficiency
during the capacity upgrade to C+L enhancement.
Three-term conjugate gradient method for X-ray luminescence computed tomography
Authors: Hou Yuqing , Tang Zijian , Yi Huangjian , Guo Hongbo , Yu Jingjing , He Xiaowei
Published: May 2021

X-ray luminescence computed tomography (XLCT) has become an emerging hybrid molecular imaging technology with high detection sensitivity and low cost. However, the inverse problem of reconstruction has severe ill-posed consequences. The original regularization algorithm needs to take much time to solve the problem. To reduce the cost of time, a three-term conjugate gradient (TTCG) algorithm is proposed for XLCT. Useful truncation information is added to the descent direction to find the optimal solution quickly in our proposed algorithm. Both numerical simulation experiments and real experiments are carried out to verify the performance of the algorithm. Experimental results show that the presented algorithm can effectively speed up the reconstruction process.
Broadband transistor-injected dual doping quantum cascade laser
Authors: Lin Zhiyuan , Wang Zhuoran , Yuan Guohui , Leburton Jean-Pierre
Published: May 2021

A novel design-friendly device called the transistor-injected dual doping quantum cascade laser (

T
I

-

D

2

Q
C
L

) with two different dopings in each stack of a homogeneous superlattice is proposed. By adjusting the base–emitter bias

V

be

of the bipolar transistor to supply electrons in the dual doping regions, charge quasi-neutrality can be achieved to generate different optical transitions in each cascading superlattice stack. These transitions are then stacked and amplified to contribute to a broad flat gain spectrum. Model calculations of a designed

T
I

-

D

2

Q
C
L

show that a broad flat gain spectrum ranging from 9.41 µm to 12.01 µm with a relative bandwidth of 0.24 can be obtained, indicating that the

T
I

-

D

2

Q
C
L

with dual doping pattern may open a new pathway to the appealing applications in both mid-infrared and terahertz frequency ranges, from wideband optical generations to advanced frequency comb technologies.
Diffraction based single pulse measurement of air ionization dynamics induced by femtosecond laser
Authors: Zhang Lin , Liu Jiamin , Gong Wenqi , Jiang Hao , Liu Shiyuan
Published: May 2021

A single pulse diffraction method to probe the plasma column evolution of the air ionization induced by the femtosecond laser pulse has been proposed. By utilizing a linearly chirped pulse as the probe light, the spatiotemporal evolution spectrum of the plasma column can be acquired in a single measurement. A method based on the Fresnel diffraction integral is proposed to extract the evolution of the phase shift after the probe light is crossing through the plasma column. Results show that the plasma expands rapidly within 7 ps due to the ionization, and then reaches a steady state with a diameter of about 80 μm with the pump pulse energy of 1 mJ. Furtherly, the temporal profile of the free electron density and the refractive index in the plasma region were determined using the corresponding physical models. The single-shot method can be expected to broaden the way for detecting the dynamics of the femtosecond laser-induced plasma.
2000 PPI silicon-based AlGaInP red micro-LED arrays fabricated via wafer bonding and epilayer lift-off
Authors: Zhao Yongzhou , Liang Jingqiu , Zeng Qinghui , Li Yang , Li Panyuan , Fan Kaili , Sun Wenchao , Lv Jinguang , Qin Yuxin , Wang Qiang , Tao Jin , Wang Weibiao
Published: May 2021

In this article, 2000 PPI red silicon-based AlGaInP micro-LED arrays were fabricated and investigated. The AlGaInP epilayer was transferred onto the silicon substrate via the In-Ag bonding technique and an epilayer lift-off process. The silicon substrate with a high thermal conductivity could provide satisfactory heat dissipation, leading to micro-LED arrays that had a stable emission spectrum with increasing current density from 20 to 420 A/cm2 along with a red-shift of the peak position from 624.69 to 627.12 nm (

Δ

λ

 = 2.43 nm). Additionally, increasing the injection current density had little effect on the CIE (x, y) of the micro-LED arrays. Further, the I-V characteristics and light output power of micro-LED arrays with different pixel sizes demonstrated that the AlGaInP red micro-LED array on a silicon substrate had excellent electrical stability and optical output.
Pre-compensation of thermally induced refractive index changes in a depressed core fully aperiodic large-pitch fiber for high average power operation
Authors: Malleville Marie-Alicia , Leconte Baptiste , Dauliat Romain , Jamier Raphaël , Schwuchow Anka , Wondraczek Katrin , Roy Philippe
Published: May 2021

To prevent the thermally induced spatial beam degradation occurring in high-power fiber lasers and amplifiers, index-depressed core “fully aperiodic large-pitch fibers” (FA-LPFs) have been designed and fabricated. In contrast to previous experimental works performed on FA-LPFs, in which the active core and the surrounding cladding material are quasi-index-matched, the core refractive index is in slight depression compared to the surrounding material (

Δ
n
≈
−

3

×

10

−
5

). Thus, the index-depressed fiber core tends first to behave as an anti-guide, preventing light from being properly guided into it. However, by increasing the absorbed pump power, the thermal load induces a parabolic refractive index change sufficient to compensate for the

−
3

×

10

−
5

index depression in the core, enabling a robust single-mode amplification at high average power. As a proof of concept, using a 110 µm depressed core FA-LPF,

M
2

values of 1.3 were demonstrated in amplifier configuration from 60 W to a maximal value of 170 W of emitted average power only limited by the available pump power.
Spectrally pure photon pair generation in asymmetric heterogeneously coupled waveguides
Authors: Ding Xiangyan , Ma Jing , Tan Liying , Helmy Amr S. , Kang Dongpeng
Published: May 2021

In this work, we develop a design methodology to generate spectrally pure photon pairs in asymmetric heterogeneously coupled waveguides by spontaneous parametric down conversion. Mode coupling in a system of waveguides is used to directly tailor the group velocity of a supermode to achieve group velocity matching that is otherwise not allowed by material dispersion. Design examples based on thin film lithium niobate waveguides are provided, demonstrating high spectral purity and temperature tunability. This approach is a versatile strategy applicable to waveguides of different materials and structures, allowing more versatility in single-photon source designs.
MXene and PtSe2 saturable absorbers for all-fibre ultrafast mid-infrared lasers
Authors: Bharathan Gayathri , Xu Luyi , Jiang Xiantao , Zhang Han , Li Ziqi , Chen Feng , Fuerbach Alex
Published: May 2021

We report on the feasibility of MXene and platinum diselenide (PtSe2) as novel saturable absorbers for the development of wavelength stabilized passively mode-locked mid-infrared fibre laser systems. After evaluating the performance of individual absorbers in a test cavity, we demonstrate a linear all-fibre laser cavity that utilizes a high reflective chirped fibre Bragg grating for wavelength selective feedback. The observed mode-locked pulse train from this Er3+:ZBLAN fibre laser has a 37 MHz repetition rate with an average power of 603 mW and a spectral width of 721 pm. Our results show that MXene and PtSe2 are promising nonlinear materials for all-integrated ultrafast fibre laser cavities for the important mid-infrared spectral region.
RHEB/mTOR hyperactivity causes cortical malformations and epileptic seizures through increased axonal connectivity
Authors: Proietti Onori Martina , Koene Linda M. C. , Schäfer Carmen B. , Nellist Mark , de Brito van Velze Marcel , Gao Zhenyu , Elgersma Ype , van Woerden Geeske M.
Published: May 2021

Hyperactivation of the mammalian target of rapamycin (mTOR) pathway can cause malformation of cortical development (MCD) with associated epilepsy and intellectual disability (ID) through a yet unknown mechanism. Here, we made use of the recently identified dominant-active mutation inRas Homolog Enriched in Brain 1(RHEB), RHEBp.P37L, to gain insight in the mechanism underlying the epilepsy caused by hyperactivation of the mTOR pathway. Focal expression of RHEBp.P37L in mouse somatosensory cortex (SScx) results in an MCD-like phenotype, with increased mTOR signaling, ectopic localization of neurons, and reliable generalized seizures. We show that in this model, the mTOR-dependent seizures are caused by enhanced axonal connectivity, causing hyperexcitability of distally connected neurons. Indeed, blocking axonal vesicle release from the RHEBp.P37L neurons alone completely stopped the seizures and normalized the hyperexcitability of the distally connected neurons. These results provide new evidence of the extent of anatomical and physiological abnormalities caused by mTOR hyperactivity, beyond local malformations, which can lead to generalized epilepsy.
Deep amplicon sequencing highlights low intra-host genetic variability of Echinococcus multilocularis and high prevalence of the European-type haplotypes in coyotes and red foxes in Alberta, Canada
Authors: Santa Maria A. , Rezansoff Andrew M. , Chen Rebecca , Gilleard John S. , Musiani Marco , Ruckstuhl Kathreen E. , Massolo Alessandro
Published: May 2021

Echinococcus multilocularis (Em) is a zoonotic parasite considered a global emergent pathogen. Recent findings indicate that the parasite is expanding its range in North America and that European-type haplotypes are circulating in western Canada. However, genetic analyses are usually conducted only on a few parasites out of thousands of individuals within each definitive host, likely underestimating the prevalence of less common haplotypes. Moreover, mixed infections with several mtDNA haplotypes in the same host have been reported, but their relative abundance within the host was never estimated. We aimed to 1) estimate the frequency of co-infections of different Em haplotypes in coyotes (Canis latrans) and red foxes (Vulpes vulpes) from western Canada and their relative abundance within the definitive hosts, 2) detect less prevalent haplotypes by sampling a larger proportion of the parasite subpopulation per host, and 3) investigate differences in the distribution of Em haplotypes in these main definitive hosts; foxes and coyotes. We extracted DNA from ~10% of the worm subpopulation per host (20 foxes and 47 coyotes) and used deep amplicon sequencing (NGS technology) on four loci, targeting the most polymorphic regions from the mitochondrial genes cox1 (814 bp), nad1 (344 bp), and cob (387 bp). We detected the presence of mixed infections with multiple Em haplotypes and with different Echinococcus species including Em and E. granulosus s.l. genotypes G8/G10, low intraspecific diversity of Em, and a higher abundance of the European-type haplotypes in both hosts. Our results suggest a population expansion of the European over the North American strain in Alberta and a limited distribution of some European-type haplotypes. Our findings indicate that deep amplicon sequencing represents a valuable tool to characterize Em in multiple hosts, to assess the current distribution and possible origins of the European strain in North America. The potential use of next-generation sequencing technologies is particularly important to understand the patterns of geographic expansion of this parasite.
Decreased dengue cases attributable to the effect of COVID-19 in Guangzhou in 2020
Authors: Jiang Liyun , Liu Yuan , Su Wenzhe , Liu Wenhui , Yang Zhicong
Published: May 2021

The dengue fever epidemic in Guangzhou may have been affected by the Coronavirus Disease 2019 (COVID-19) pandemic. The number of dengue cases dropped drastically in 2020, and there have been only 2 local cases, suggesting that dengue has not become endemic in Guangzhou.
Genomic GC content drifts downward in most bacterial genomes
Authors: Ely Bert
Published: May 2021

In every kingdom of life, GC->AT transitions occur more frequently than any other type of mutation due to the spontaneous deamination of cytidine. In eukaryotic genomes, this slow loss of GC base pairs is counteracted by biased gene conversion which increases genomic GC content as part of the recombination process. However, this type of biased gene conversion has not been observed in bacterial genomes, so we hypothesized that GC->AT transitions cause a reduction of genomic GC content in prokaryotic genomes on an evolutionary time scale. To test this hypothesis, we used a phylogenetic approach to analyze triplets of closely related genomes representing a wide range of the bacterial kingdom. The resulting data indicate that genomic GC content is drifting downward in bacterial genomes where GC base pairs comprise 40% or more of the total genome. In contrast, genomes containing less than 40% GC base pairs have fewer opportunities for GC->AT transitions to occur so genomic GC content is relatively stable or actually increasing. It should be noted that this observed change in genomic GC content is the net change in shared parts of the genome and does not apply to parts of the genome that have been lost or acquired since the genomes being compared shared common ancestor. However, a more detailed analysis of two Caulobacter genomes revealed that the acquisition of mobile elements by the two genomes actually reduced the total genomic GC content as well.
Ecological impacts of the LED-streetlight retrofit on insectivorous bats in Singapore
Authors: Lee Kenneth Ee Meng , Lum W. H. Deon , Coleman Joanna L.
Published: May 2021

Cities around the world are transitioning to more efficient lighting schemes, especially retrofitting traditional, high-pressure sodium (HPS) streetlights with light-emitting diode (LED) lights. Although these initiatives aim to address the problems of urban sustainability and save money, the ecological impacts of these retrofits remain poorly understood, especially in brightly lit cities and in the tropics, where urbanisation is most rapid. We performed an experimental study of the retrofit in Singapore–focusing on insectivorous bats, whose activity we monitored acoustically along paired control (HPS-lit) and treatment (LED-lit) streets. We recorded seven species along these streets, but only obtained enough recordings to measure the effect of light type for three of them–all of which can reasonably be described as urban adapters. The strongest predictor of bat activity (an index of habitat use) was rainfall–it has a positive effect. Light type did not influence bat activity or species composition of the bat assemblage along these streets, though it did interact with the effects of rainfall and traffic noise for one bat species. Ultimately, the retrofit may be ecologically meaningless to urban-adapted, tropical insectivores that already experience high levels of light pollution as they do in Singapore. However, while our findings may appear reassuring to those concerned with such retrofits in other tropical and/or brightly-lit cities, they also highlight the contextual nature of ecological impacts. We point out that they should not be prematurely generalised to other locales and systems. In particular, they do not imply no impact on species that are less urban-adapted, and there is a clear need for further studies, for example, on responses of other foraging guilds and of bats (and insects) throughout the tropics.
Two new Nothophytophthora species from streams in Ireland and Northern Ireland: Nothophytophthora irlandica and N. lirii sp. nov.
Authors: O’Hanlon Richard , Destefanis Maria , Milenković Ivan , Tomšovský Michal , Janoušek Josef , Bellgard Stanley E. , Weir Bevan S. , Kudláček Tomáš , Horta Jung Marilia , Jung Thomas
Published: May 2021

Slow growing oomycete isolates with morphological resemblance toPhytophthorawere obtained from forest streams during routine monitoring for the EU quarantine forest pathogenPhytophthora ramorumin Ireland and Northern Ireland. Internal Transcribed Spacer (ITS) sequence analysis indicated that they belonged to two previously unknown species ofNothophytophthora, a recently erected sister genus ofPhytophthora. Morphological and temperature-growth studies were carried out to characterise both new species. In addition, Bayesian and Maximum-Likelihood analyses of nuclear 5-loci and mitochondrial 3-loci datasets were performed to resolve the phylogenetic positions of the two new species. Both species were sterile, formed chlamydospores and partially caducous nonpapillate sporangia, and showed slower growth than any of the six knownNothophytophthoraspecies. In all phylogenetic analyses both species formed distinct, strongly supported clades, closely related toN.chlamydosporaandN.valdivianafrom Chile. Based on their unique combination of morphological and physiological characters and their distinct phylogenetic positions the two new species are described asNothophytophthora irlandicasp. nov. andN.liriisp. nov. Their potential lifestyle and geographic origin are discussed.
“I’m not gonna be able to do anything about it, then what’s the point?”: A broad group of stakeholders identify barriers and facilitators to HCV testing in a Massachusetts jail
Authors: Wurcel Alysse G. , Reyes Jessica , Zubiago Julia , Koutoujian Peter J. , Burke Deirdre , Knox Tamsin A. , Concannon Thomas , Lemon Stephenie C. , Wong John B. , Freund Karen M. , Beckwith Curt G. , LeClair Amy M.
Published: May 2021

Background

Despite national guidelines promoting hepatitis C virus (HCV) testing in prisons, there is substantial heterogeneity on the implementation of HCV testing in jails. We sought to better understand barriers and opportunities for HCV testing by interviewing a broad group of stakeholders involved in HCV testing and treatment policies and procedures in Massachusetts jails.

Methods

We conducted semi-structured interviews with people incarcerated in Middlesex County Jail (North Billerica, MA), clinicians working in jail and community settings, corrections administrators, and representatives from public health, government, and industry between November 2018—April 2019.

Results

51/120 (42%) of people agreed to be interviewed including 21 incarcerated men (mean age 32 [IQR 25, 39], 60% non-White). Themes that emerged from these interviews included gaps in knowledge about HCV testing and treatment opportunities in jail, the impact of captivity and transience, and interest in improving linkage to HCV care after release. Many stakeholders discussed stigma around HCV infection as a factor in reluctance to provide HCV testing or treatment in the jail setting. Some stakeholders expressed that stigma often led decisionmakers to estimate a lower “worth” of incarcerated individuals living with HCV and therefore to decide against paying for HCV testing.”.

Conclusion

All stakeholders agreed that HCV in the jail setting is a public health issue that needs to be addressed. Exploring stakeholders’ many ideas about how HCV testing and treatment can be approached is the first step in developing feasible and acceptable strategies.
Launching a saliva-based SARS-CoV-2 surveillance testing program on a university campus
Authors: Ehrenberg Alexander J. , Moehle Erica A. , Brook Cara E. , Doudna Cate Andrew H. , Witkowsky Lea B. , Sachdeva Rohan , Hirsh Ariana , Barry Kerrie , Hamilton Jennifer R. , Lin-Shiao Enrique , McDevitt Shana , Valentin-Alvarado Luis , Letourneau Kaitlyn N. , Hunter Lauren , Keller Amanda , Pestal Kathleen , Frankino Phillip A. , Murley Andrew , Nandakumar Divya , Stahl Elizabeth C. , Tsuchida Connor A. , Gildea Holly K. , Murdock Andrew G. , Hochstrasser Megan L. , O’Brien Elizabeth , Ciling Alison , Tsitsiklis Alexandra , Worden Kurtresha , Dugast-Darzacq Claire , Hays Stephanie G. , Barber Colin C. , McGarrigle Riley , Lam Emily K. , Ensminger David C. , Bardet Lucie , Sherry Carolyn , Harte Anna , Nicolette Guy , Giannikopoulos Petros , Hockemeyer Dirk , Petersen Maya , Urnov Fyodor D. , Ringeisen Bradley R. , Boots Mike , Doudna Jennifer A. ,   on behalf of the IGI SARS-CoV-2 Testing Consortium
Published: May 2021

Regular surveillance testing of asymptomatic individuals for SARS-CoV-2 has been center to SARS-CoV-2 outbreak prevention on college and university campuses. Here we describe the voluntary saliva testing program instituted at the University of California, Berkeley during an early period of the SARS-CoV-2 pandemic in 2020. The program was administered as a research study ahead of clinical implementation, enabling us to launch surveillance testing while continuing to optimize the assay. Results of both the testing protocol itself and the study participants’ experience show how the program succeeded in providing routine, robust testing capable of contributing to outbreak prevention within a campus community and offer strategies for encouraging participation and a sense of civic responsibility.
Dog visits in nursing homes – increase complexity or keep it simple? A randomised controlled study
Authors: Thodberg Karen , Videbech Poul B. , Hansen Tia G. B. , Pedersen Anne Bak , Christensen Janne W.
Published: May 2021

Objective

To compare the immediate response of nursing home residents to dog visits with or without an activity, and the impact of cognitive ability.

Methods

In a randomly controlled trial, 174 nursing home residents were allocated to 12 bi-weekly 10-minute visits: either ordinary dog visits (D, n = 57, 49 analysed), dog visits with an activity (DA, n = 56, 48 analysed), or visits with activity but no dog (A, n = 61, 54 analysed). We recorded frequency and duration of residents’ verbal and physical interactions with the dog and persons. Data were analysed in three periods of four visits (period 1–3) as binomial variables (generalised linear models) or durations (non-parametric statistics).

Results

Both visit type and impairment level affected the likelihood of interacting with the dog (D and DA). In some periods increased cognitive impairment lowered odds of touching the dog in DA visits (period 1: F1,85 = 5.17, P < 0.05) and talking to it directly (period 1: F1,90 = 4.60, P < 0.05; period 3: F1,87 = 5.34, P < 0.05). Throughout, residents talked less to persons during DA visits compared to D and A (P = 0.01–0.05), and level of cognitive impairment correlated negatively with talk duration (P < 0.001). Generally, high cognitive impairment level lowered odds of interacting with (period 1: F1,89 = 7.89, P < 0.01; period 2: F1,97 = 6.76, P = 0.01; period 3: F1,92 = 13.57, P < 0.001) and talking about the activities (period 1: F1,89 = 13.78, P <0.001; period 2: F1,88 = 3.27, P = 0.07; period 3: F1,86 = 3.88, P = 0.05).

Conclusion

Visits without specific activities stimulated residents to interact with the dog, whereas increasing the complexity of dog visits by adding activities resulted in less interaction with the dog for severely impaired residents. The optimal dog visit for the less cognitively impaired residents could include activities and thereby a possibility to interact with the dog in different ways, whereas for severely impaired residents, just being with the dog seems more appropriate.
Effects of combined training performed two or four times per week on 24-h blood pressure, glycosylated hemoglobin and other health-related outcomes in aging individuals with hypertension: Rationale and study protocol of a randomized clinical trial
Authors: Ferrari Rodrigo , Domingues Lucas Betti , Carpes Leandro de Oliveira , Frank Paula de Azevedo , Schneider Vinícius Mallmann , Fuchs Sandra C. ,   the GET Study Group
Published: May 2021

Background

Acute blood pressure lowering after exercise seems to predict the extent of blood pressure reduction after chronic exercise training interventions. Based on that, the same weekly amount of exercise performed more frequently could be more beneficial for controlling blood pressure.

Purpose

To compare the effects of a combined training program (resistance plus aerobic exercise) performed four or two times per week on 24-h ambulatory blood pressure and other health-related outcomes in middle-aged and older individuals with hypertension.

Methods

This study will be a randomized, parallel group, two-arm, superiority trial. Ninety-eight participants aged 50–80 years with a previous physician diagnosis of hypertension will be randomized to perform two or four sessions per week of combined training using the same total weekly overload. Primary outcomes will be 24-h ambulatory blood pressure and glycosylated hemoglobin; secondary outcomes will be endothelial function, physical fitness and quality of life. The outcomes will be assessed at baseline and at the end of 12 weeks period.

Results

Our conceptual hypothesis is that a combined exercise program performed four or two times per week with equalized weekly volume/overload will improve all outcomes in comparison to the baseline values, and that reductions in 24-h blood pressure and glycosylated hemoglobin will be more pronounced in the group that trained four times a week than twice. The results of this trial are expected to provide evidences to support that higher weekly frequency of combined training should be emphasized in aging adults with hypertension.
Hurricanes and hashtags: Characterizing online collective attention for natural disasters
Authors: Arnold Michael V. , Dewhurst David Rushing , Alshaabi Thayer , Minot Joshua R. , Adams Jane L. , Danforth Christopher M. , Dodds Peter Sheridan
Published: May 2021

We study collective attention paid towards hurricanes through the lens ofn-grams on Twitter, a social media platform with global reach. Using hurricane name mentions as a proxy for awareness, we find that the exogenous temporal dynamics are remarkably similar across storms, but that overall collective attention varies widely even among storms causing comparable deaths and damage. We construct ‘hurricane attention maps’ and observe that hurricanes causing deaths on (or economic damage to) the continental United States generate substantially more attention in English language tweets than those that do not. We find that a hurricane’s Saffir-Simpson wind scale category assignment is strongly associated with the amount of attention it receives. Higher category storms receive higher proportional increases of attention per proportional increases in number of deaths or dollars of damage, than lower category storms. The most damaging and deadly storms of the 2010s, Hurricanes Harvey and Maria, generated the most attention and were remembered the longest, respectively. On average, a category 5 storm receives 4.6 times more attention than a category 1 storm causing the same number of deaths and economic damage.
Identifying the chloroperoxyl radical in acidified sodium chlorite solution
Authors: Kawata Hiroyuki , Kohno Masahiro , Nukina Kohei , Horiuchi Isanori , Goda Hisataka , Kuwahara Tomomi , Yoshimori Kosei , Miyaji Akimitsu , Kamachi Toshiaki , Yoshikawa Toshikazu
Published: May 2021

The present study identified the active radical species in acidic sodium chlorite and investigated the feasibility of quantifying these species with the diethylphenylenediamine (DPD) method. Electron spin resonance (ESR) spectroscopy was used to identify the active species generated in solutions containing sodium chlorite (NaClO2). The ESR signal was directly observed in an acidified sodium chlorite (ASC) aqueous solution at room temperature. This ESR signal was very long-lived, indicating that the radical was thermodynamically stable. The ESR parameters of this signal did not coincide with previously reported values of the chlorine radical (Cl●) or chlorine dioxide radical (O = Cl●-O and O = Cl-O●). We refer to this signal as being from the chloroperoxyl radical (Cl-O-O●). Quantum chemical calculations revealed that the optimal structure of the chloroperoxyl radical is much more thermodynamically stable than that of the chlorine dioxide radical. The UV-visible spectrum of the chloroperoxyl radical showed maximum absorbance at 354 nm. This absorbance had a linear relationship with the chloroperoxyl radical ESR signal intensity. Quantifying the free chlorine concentration by the DPD method also revealed a linear relationship with the maximum absorbance at 354 nm, which in turn showed a linear relationship with the chloroperoxyl radical ESR signal intensity. These linear relationships suggest that the DPD method can quantify chloroperoxyl radicals, which this study considers to be the active species in ASC aqueous solution.