bluuebunny/crossref_metadata_2025 huggingface dataset:
Monte-Carlo wavefunction approach for the spin dynamics of recombining radicals
Authors: Keens Robert H , Kattnig Daniel R
Published: July 2020

We adapt the Monte-Carlo wavefunction (MCWF) approach to treat the open-system spin dynamics of radical pairs subject to spin-selective recombination reactions. For these systems, non-Lindbladian master equations are widely employed, which account for recombination via the non trace-preserving Haberkorn superoperator in combination with reaction-dependent exchange and singlet–triplet dephasing terms. We show that this type of master equation can be accommodated in the MCWF approach, by introducing a second type of quantum jump that accounts for the reaction simply by suitably terminating the propagation. In this way, we are able to evaluate approximate solutions to the time-dependent radical pair survival probability for systems that have been considered untreatable with the master equation approach until now. We explicate the suggested approach with calculations for radical pair reactions that have been suggested to be relevant for the quantum compass of birds and related phenomena.
Topological superconductivity facilitated by exchange interaction on the surface of FeTe0.5Se0.5
Authors: Yang Chih-Kai , Lee Chi-Hsuan
Published: July 2020

FeTe1−x
Se
x
is a family of iron-based superconductors with a well-known critical temperature (T
c) of 14.5 K for x = 0.45. Also well-established is the presence of topological surface states of FeTe0.55Se0.45 in which topological superconductivity sets in. By using density functional calculations and the Bardeen–Cooper–Schrieffer (BCS) theory for traditional superconductors we calculated the T
c of the surface layers of FeTe0.5Se0.5 with the exchange interaction as the source of attractive force to form the Cooper pairs. The estimated T
c is in reasonable agreement with the experimental value and suggests that the exchange interaction is behind the topological superconductivity on the surface of FeTe0.55Se0.45.
Possibility of observation of hidden-bottom pentaquark resonances in bottomonium photoproduction on protons and nuclei near threshold
Authors: Paryev E. Ya.
Published: July 2020

We study the

meson photoproduction on protons and nuclei at near-threshold center-of-mass energies below 11.4 GeV (or at the corresponding photon laboratory energies

below 68.8 GeV). We calculate the absolute excitation functions for the nonresonant and resonant photoproduction of

mesons off protons at incident photon laboratory energies of 63-68 GeV by considering direct (

) and two-step (

,

,

)

production channels within different scenarios for the nonresonant total cross section of the elementary reaction

and for branching ratios of the decays

,

, and

. We also calculate an analogous function for the photoproduction of

mesons on the 12C and 208Pb target nuclei in the near-threshold center-of-mass beam energy region of 9.0-11.4 GeV by considering the respective incoherent direct (

) and two-step (

,

,

and

,

,

)

) production processes using a nuclear spectral function approach. We demonstrate that a detailed scan of the

total photoproduction cross section on proton and nuclear targets in the near-threshold energy region in future high-precision experiments at the proposed high-luminosity electron-ion colliders EIC and EicC in the US and China should provide a definite result for or against the existence of the nonstrange hidden-bottom pentaquark states

and

(

=1, 2, 3) as well as clarify their decay rates.
Glial cell responses on tetrapod-shaped graphene oxide and reduced graphene oxide 3D scaffolds in brain in vitro and ex vivo models of indirect contact
Authors: Schmitt Christina , Rasch Florian , Cossais François , Held-Feindt Janka , Lucius Ralph , Vázquez Adrian Romani , Nia Ali Shaygan , Lohe Martin R , Feng Xinliang , Mishra Yogendra K , Adelung Rainer , Schütt Fabian , Hattermann Kirsten
Published: July 2020

Brain implants are promising instruments for a broad variety of nervous tissue diseases with a wide range of applications, e.g. for stimulation, signal recording or local drug delivery. Recently, graphene-based scaffold materials have emerged as attractive candidates as neural interfaces, 3D scaffolds, or drug delivery systems due to their excellent properties like flexibility, high surface area, conductivity, and lightweight. To date, however, there is a lack of appropriate studies of the foreign body response, especially by glial cells, towards graphene-based materials. In this work, we investigated the effects of macroscopic, highly porous (>99.9%) graphene oxide (GO) and reduced graphene oxide (rGO) (conductivity ∼1 S m−1) scaffolds with tailorable macro- and microstructure on human astrocyte and microglial cell viability and proliferation as well as expression of neuroinflammation and astrogliosis associated genes in an indirect contact approach. In this in vitro model, as well as ex vivo in organotypic murine brain slices, we could demonstrate that both GO and rGO based 3D scaffolds exert slight effects on the glial cell populations which are the key players of glial scar formation. These effects were in most cases completely abolished by curcumin, a known anti-inflammatory and anti-fibrotic drug that could in perspective be applied to brain implants as a protectant.
US students hit by extra demands
Authors: Gwynne Peter
Published: July 2020

Graduate students under COVID-19 lockdown complain they are being unfairly asked to carry out more tasks such as online teaching, as Peter Gwynne reports
From inflation to science policy
Authors: Sato Katsuhiko
Published: July 2020

Physicist Katsuhiko Sato from the University of Tokyo talks to Graham Jones about his work on inflation and the future of physics in Japan
Kicking the habit
Authors: McKenzie James
Published: July 2020

We all knew that we should have travelled less and video conferenced more. But with COVID-19, we have no other choice says James McKenzie
Sea-power success
Authors: Ranson John
Published: July 2020

In response to Stephen Ornes’ feature “Turning water into watts” (March pp31–34) in which he explores the research and business ventures looking into wave energy, and harnessing the vast power of the world’s oceans.
Viscosity doesn’t get any less than this
Authors: Cartlidge Edwin
Published: July 2020

Physicists claim to have deduced the minimum viscosity of any fluid that takes into account the quantum-mechanical nature of molecular interactions, as Edwin Cartlidge reports
Ground states of strontium and bromine isotopes violate mirror-symmetry
Authors: Jarman Sam
Published: July 2020

Physicists in the US have made the surprising discovery that two nuclear isotopes with exactly mirrored numbers of protons and neutrons have different ground states.
Shiitake happens! Fungi grow faster when lightning strikes
Authors: Cockbill Louisa
Published: July 2020

Japanese researchers are closing in on understanding why electrical storms have a positive influence on the growth of some fungi.
Power supply efficiency in dual magnetron large area sputter coatings
Authors: Heintze Moritz , Swiatnicki Jakub
Published: July 2020

In large area sputter coating of glass, the consumption of electric power is one of the major cost drivers. This applies especially to dielectric transparent coatings which are relatively thick and for which sputter yields and rates can be rather low. These materials are usually sputtered from dual magnetrons using medium frequency (sine wave) or bipolar (square wave) power supplies at frequencies up to 100 kHz. Frequencies at 50 kHz or higher are beneficial for suppressing arcing on the target surface, and the power required to achieve viable sputter rates is often high, making the power consumption a significant cost contribution. In this study we look at the effect of the power supply technology and frequency on the sputter rate and the sputtered layer thickness per electrical energy input. The tests were carried out with aluminum dual planar targets and with TiOx dual rotary targets. At low frequencies around 20 kHz, the bipolar generator can yield about 10% higher sputtering rates at the same input power. At about 40 kHz, which is often chosen to minimize arcing, the rates from the two power supplies are about equal.
What Makes Opportunistic GP Interventions Effective? An Analysis of Behavior Change Techniques Used in 237 GP-Delivered Brief Interventions for Weight Loss
Authors: Bourhill Jana , Lee Joseph J , Frie Kerstin , Aveyard Paul , Albury Charlotte
Published: July 2020

Background

Evidence shows that clinician-delivered brief opportunistic interventions are effective in obesity, and guidelines promote their use. However, there is no evidence on how clinicians should do this, and guidelines are not based on clinical evidence.

Purpose

A trial (Brief Interventions for Weight Loss [BWeL]) showed that brief opportunistic interventions on obesity that endorsed, offered, and facilitated referral to community weight management service (CWMS) led to 77% agreeing to attend, and 40% attending CWMS, as well as significantly greater weight loss than control at 12 months. We assessed which behavior change techniques (BCTs) doctors used that were associated with CWMS attendance.

Methods

We coded 237 recorded BWeL interventions using the behavioral change techniques version one taxonomy. We also coded the BWeL training video to examine delivery of recommended BCTs. Mixed effects logistic regression assessed the association between each BCT, the total number of BCTs, and delivery of recommended BCTs, with patient’s agreement to attend and actual CWMS attendance.

Results

Of 237 patients, 133 (56%) agreed to attend and 109 (46%) attended. Thirteen BCTs were used more than eight times but none of the 13 were associated with increased attendance. One, “practical social support,” was significantly associated with increased patient agreement (odds ratio [OR] = 4.80, 95% confidence interval [CI] = 1.15, 20.13). Delivery of recommended BCTs and the total number of BCTs used were both associated with increased agreement (OR = 1.56, 95% CI = 1.09, 2.23 and OR = 1.34, 95% CI = 1.03, 1.75, respectively), but not attendance at CWMS (OR = 1.20, 95% CI = 0.98–1.47 and OR = 1.08, 95% CI = 0.94–1.24, respectively).

Conclusions

There is no evidence that particular BCT can increase the effectiveness of brief opportunistic interventions for obesity in adults. However, using more BCTs and delivery of recommended BCTs may increase agreement to attend community weight management services.
“This place means freedom to me”: needs-based engagement with marginalized migrant Muslim women in London
Authors: Thompson Naomi , Nasimi Rabia
Published: July 2020

This paper draws on a case study of a community-based organization working with marginalized Muslim women in London from refugee and migrant backgrounds. The organization delivers a model of practice that involves English for Speakers of Other Languages (ESOL) classes, practical/informative workshops, and social integration in a women-only community space rather than these elements being accessed separately in often formal spaces. The article draws on data collected as part of the first year of an evaluation of a three-year funded project to engage the women. The data include registration information about the participant group, a bespoke workshop evaluation form completed by the women each month, and interviews with beneficiaries, volunteers, and staff. Our research finds that an integrated, bottom-up approach is successful in engaging isolated women and impacts on their lives through increased well-being, knowledge and skills, empowerment, and freedom. Whilst asset-focused interventions have become dominant in community development, there is a danger that a deliberate focus away from the needs of vulnerable groups may cement rather than tackle inequalities, and collude with a political and neoliberal agenda that promotes individualism and austerity. We argue it is necessary to develop interventions that respond to the needs of marginalized groups before building on people’s strengths to address them. Our case study offers evidence for this.
Potential Influence of Menstrual Status and Sex Hormones on Female Severe Acute Respiratory Syndrome Coronavirus 2 Infection: A Cross-sectional Multicenter Study in Wuhan, China
Authors: Ding Ting , Zhang Jinjin , Wang Tian , Cui Pengfei , Chen Zhe , Jiang Jingjing , Zhou Su , Dai Jun , Wang Bo , Yuan Suzhen , Ma Wenqing , Ma Lingwei , Rong Yueguang , Chang Jiang , Miao Xiaoping , Ma Xiangyi , Wang Shixuan
Published: July 2020

Background

Recent studies have indicated that females with coronavirus disease 2019 (COVID-19) have a lower morbidity, severe case rate, and mortality and better outcome than those of male individuals. However, the reasons remained to be addressed.

Methods

To find the factors that potentially protect females from COVID-19, we recruited all confirmed patients hospitalized at 3 branches of Tongji Hospital (N = 1902), and analyzed the correlation between menstrual status (n = 509, including 68 from Mobile Cabin Hospital), female hormones (n = 78), and cytokines related to immunity and inflammation (n = 263), and the severity/clinical outcomes in female patients <60 years of age.

Results

Nonmenopausal female patients had milder severity and better outcome compared with age-matched men (P < .01 for both). Menopausal patients had longer hospitalization times than nonmenopausal patients (hazard ratio [HR], 1.91 [95% confidence interval {CI}, 1.06–3.46]; P = .033). Both anti-Müllerian hormone (AMH) and estradiol (E2) showed a negative correlation with severity of infection (adjusted HR, 0.146 [95% CI, .026–.824], P = .029 and 0.304 [95% CI, .092–1.001], P = .05, respectively). E2 levels were negatively correlated with interleukin (IL) 2R, IL-6, IL-8, and tumor necrosis factor alpha in the luteal phase (P = .033, P = .048, P = .054, and P = .023) and C3 in the follicular phase (P = .030).

Conclusions

Menopause is an independent risk factor for female COVID-19 patients. AMH and E2 are potential protective factors, negatively correlated with COVID-19 severity, among which E2 is attributed to its regulation of cytokines related to immunity and inflammation.
The Meaning of Freedom: Slave Self-Purchase and the Making of Free Labour in Martinique
Authors: Heath Elizabeth A
Published: July 2020

This article examines the introduction of legalized slave savings and compulsory slave self-purchase—the pécule légal and rachat forcé—by the Mackau Laws in the French colony of Martinique in the last years of the July Monarchy. Drawing on official correspondence, political debates, published pamphlets and individual cases of slave self-purchase, it examines official efforts to replace a system of bondage rooted in direct, personal domination and explicit violence with a system of colonial labour based on free labour and impersonal social controls. Their efforts were profoundly shaped by two sets of actors: members of the pro-slavery lobby and the enslaved. Together these two groups defined a minimal standard of free labour that would have far-reaching impact on colonial labour policy in the post-emancipation period.
Bone density, microarchitecture and tissue quality after 1 year of treatment with dolutegravir/abacavir/lamivudine
Authors: Soldado-Folgado Jade , Lerma-Chippirraz Elisabeth , Arrieta-Aldea Itziar , Bujosa Daniel , García-Giralt Natalia , Pineda-Moncusi Marta , Trenchs-Rodríguez Marta , Villar-García Judit , González-Mena Alicia , Díez-Pérez Adolfo , Brown Todd T , Knobel Hernando , Güerri-Fernández Robert
Published: July 2020

Background

Bone mineral density (BMD) decreases with ART initiation with a tenofovir disoproxil fumarate-containing regimen, although bone tissue quality increases. The impact of dolutegravir (DTG)/abacavir (ABC)/lamivudine (3TC)-based ART initiation on bone health parameters is not clear.

Objectives

To study the impact of DTG/ABC/3TC-based therapy on bone health parameters in ART-naive individuals with HIV after 48 weeks of treatment.

Methods

An observational, prospective and analytical study of treatment-naive patients with HIV undergoing a DTG/ABC/3TC-based regimen at 48 week follow-up. Changes in bone strength parameters (BMD, bone microarchitecture and bone tissue quality) were assessed with non-parametric methods.

Results

Sixteen HIV-infected ART-naive patients starting DTG/ABC/3TC were included. BMD in the lumbar spine showed a significant decrease of −2.25% (P = 0.007) and −4.1% in the femoral neck (P = 0.007). Bone microarchitecture, as measured by trabecular bone score, also decreased significantly by −2.5% (P = 0.03). In contrast, bone quality [bone material strength index (BMi)], as measured by microindentation, significantly increased with respect to baseline after 48 weeks of treatment, showing better bone properties of +6.53% (P < 0.001). No significant changes were found in bone turnover markers. In addition, a positive significant correlation between the CD4/CD8 cell count ratio at baseline and changes in BMSi after 48 weeks of treatment was observed (Spearman’s rho = 0.4974; P = 0.04).

Conclusions

After a 48 week treatment with DTG/ABC/3TC-based ART, BMD and trabecular bone score decreased while bone tissue quality, as measured by microindentation, improved significantly. The state of the immune system at ART initiation is related to bone quality recovery. An overarching approach to assess bone toxicity in ART-treated patients is needed.
Ruminal cellulolytic bacteria abundance leads to the variation in fatty acids in the rumen digesta and meat of fattening lambs
Authors: Zhang Zhian , Niu Xiaolin , Li Fei , Li Fadi , Guo Long
Published: July 2020

Ruminal cellulolytic bacteria could be a diagnostic tool for determining the subacute rumen acidosis (SARA) risk in individual ruminants; however, a limited number of studies have investigated the effects of the abundance of ruminal cellulolytic bacteria on the fatty acid (FA) composition of the rumen digesta and the muscle of sheep. Thus, the objective of this study was to evaluate the effect of the variation of rumen cellulolytic bacteria on the rumen fermentation, rumen digesta, and muscle FA composition of fattening lambs fed an identical diet. Forty-eight lambs were reared in individual units and fed a high-concentrate diet consisting of 20% forage and 80% concentrate. All lambs were adapted to diets and facilities for 14 d, and sampling was for 63 d. At the end of the experiment, the rumen fluid, rumen digesta, and longissimus dorsi were collected after slaughter for the measurement of volatile fatty acids, ruminal bacterial DNA, rumen digesta, and muscle FAs. The lambs were classified into the lower cellulolytic bacteria (LCB, n = 10) group and the higher cellulolytic bacteria (HCB, n = 10) group according to the abundance of pH-sensitive cellulolytic bacteria (Ruminococcus albus, Ruminococcus flavefaciens, Fibrobacter succinogenes, and Butyrivibrio fibrisolvens) in the rumen. Ruminal acetate concentration was positively correlated with the number of R. flavefaciens, F. Succinogenes, and B. fibrisolvens (P < 0.05, r > 0.296), whereas propionate and valerate concentrations were negatively correlated with the amount of F. succinogenes and B. fibrisolvens (P < 0.05, r > 0.348). Compared with the LCB group, the acetate (P = 0.018) as well as acetate to propionate ratio (P = 0.012) in the HCB group was higher, but the valerate ratio was lower (P = 0.002). The proportions of even-chain FAs and odd- and branched-chain fatty acid in the rumen digesta of lambs with the HCB were higher (P < 0.05), while the polyunsaturated fatty acids decreased than those in the LCB lambs (P < 0.05), but those FA proportions in the meat were similar between the two groups. The proportion of C17:0 in the meat of lambs in the HCB group was lower than that of lambs in the LCB group (P = 0.033). The proportions of conjugated linoleic acid in rumen digesta and meat were both higher in the HCB group than that in the LCB group (P = 0.046). These results indicated that the ruminal cellulolytic bacteria can alter the FA compositions in rumen digesta and further influenced the FA compositions in the meat of sheep.
Xylanase increased the energetic contribution of fiber and improved the oxidative status, gut barrier integrity, and growth performance of growing pigs fed insoluble corn-based fiber
Authors: Petry Amy L , Huntley Nichole F , Bedford Michael R , Patience John F
Published: July 2020

The experimental objective was to investigate the impact of xylanase on the bioavailability of energy, oxidative status, and gut function of growing pigs fed a diet high in insoluble fiber and given a longer adaptation time than typically reported. Three replicates of 20 gilts with an initial body weight (BW) of 25.43 ± 0.88 kg were blocked by BW, individually housed, and randomly assigned to one of four dietary treatments: a low-fiber control (LF) with 7.5% neutral detergent fiber (NDF), a 30% corn bran without solubles high-fiber control (HF; 21.9% NDF), HF + 100 mg/kg xylanase (HF + XY; Econase XT 25P), and HF + 50 mg/kg arabinoxylan-oligosaccharide (HF + AX). Gilts were fed ad libitum for 36 d across two dietary phases. Pigs and feeders were weighed on days 0, 14, 27, and 36. On day 36, pigs were housed in metabolism crates for a 10-d period, limit fed (80% of average ad libitum intake), and feces and urine were collected the last 72 h to determine the digestible energy (DE) and metabolizable energy (ME). On day 46, serum and ileal and colonic tissue were collected. Data were analyzed as a linear mixed model with block and replication as random effects, and treatment, time, and treatment × time as fixed effects. There was a significant treatment × time interaction for BW, average daily gain (ADG), and gain to feed (G:F; P < 0.001). By design, BW at day 0 did not differ; at day 14, pigs fed LF were 3.5% heavier, and pigs fed HF + XY, when compared with HF, were 4% and 4.2% heavier at days 27 and 36, respectively (P < 0.001). From day 14 to 27 and day 27 to 36, when compared with HF, HF + XY improved ADG by 12.4% and 10.7% and G:F by 13.8% and 8.8%, respectively (P < 0.05). Compared with LF, HF decreased DE and ME by 0.51 and 0.42 Mcal/kg, respectively, but xylanase partially mitigated that effect by increasing DE and ME by 0.15 and 0.12 Mcal/kg, over HF, respectively (P < 0.05). Pigs fed HF + XY had increased total antioxidant capacity in the serum and ileum (P < 0.05) and tended to have less circulating malondialdehyde (P = 0.098). Pigs fed LF had increased ileal villus height, and HF + XY and HF + AX had shallower intestinal crypts (P < 0.001). Pigs fed HF + XY had increased ileal messenger ribonucleic acid abundance of claudin 4 and occludin (P < 0.05). Xylanase, but not AX, improved the growth performance of pigs fed insoluble corn-based fiber. This was likely a result of the observed increase in ME, improved antioxidant capacity, and enhanced gut barrier integrity, but it may require increased adaptation time to elicit this response.
Multiple Coexisting Species and the First Known Case of a Cheater in Epicephala (Gracillariidae) Associated with a Species of Glochidion (Phyllanthaceae) in Tropical Asia
Authors: Wang Zhibo , Yang Xiaofei , Zhang Zhenguo , Shi Fuchen , Li Houhun
Published: July 2020

Glochidion plants and Epicephala moths played different roles and kept the balance in the mutualism. We studied the four coexisting Epicephala species on Glochidion sphaerogynum in detail and reconstructed the phylogenic tree of 40 Gracillariidae species. The results showed that one of them (Epicephala impolliniferens) did not pollinate G. sphaerogynum, because of lacking the specialized structure of carrying pollen. These results suggested that E. impolliniferens acted as a ‘cheater’ in the system. The phylogenetic analyses suggested that E. impolliniferens derived from a pollinating species, and had secondarily gave up the ability to pollinate. This is a typical phenomenon of mutualism reversal. The phenomenon exhibits the co-evolutionary diversification under selection pressures.
Shielding effect of radiation dose reduction fiber during the use of C-arm fluoroscopy: a phantom study
Authors: Cha Hyemi , Lee Kisung , Park Moon Seok , Lee Kyoung Min , Cho Kyeyoung , Sung Ki Hyuk
Published: July 2020

This study evaluated the shielding effect of a newly developed dose-reduction fiber (DRF) made from barium sulfate, in terms of radiation doses delivered to patients’ radiosensitive organs and operator during C-arm fluoroscopy and its impact on the quality of images. A C-arm fluoroscopy unit was placed beside a whole-body phantom. Radiophotoluminescent glass dosimeters were attached to the back and front of the whole-body phantom at 20 cm intervals. Radiation doses were measured without DRF and with it applied to the back (position 1), front (position 2) or both sides (position 3) of the phantom. To investigate the impact of DRF on the quality of fluoroscopic images, step-wedge and modulation transfer function phantoms were used. The absorbed radiation doses to the back of the phantom significantly decreased by 25.3–88.8% after applying DRF to positions 1 and 3. The absorbed radiation doses to the front of the phantom significantly decreased by 55.3–93.6% after applying DRF to positions 2 and 3. The contrast resolution values for each adjacent step area fell in the range 0.0119–0.0209, 0.0128–0.0271, 0.0135–0.0339 and 0.0152–0.0339 without and with DRF applied to positions 1, 2 and 3, respectively. The investigated DRF effectively reduces absorbed radiation doses to patients and operators without decreasing the quality of C-arm fluoroscopic images. Therefore, routine clinical use of the DRF is recommended during the use of C-arm fluoroscopy.
Factors associated with the intention to participate in activities during a nuclear disaster situation among firefighters
Authors: Iyama Keita , Takano Yoshinori , Takahashi Tsukasa , Hasegawa Arifumi
Published: July 2020

Willingness to participate in activities during a nuclear disaster situation among firefighters is low. Thus, we aimed to identify the factors affecting the intention to participate in nuclear disaster activities. A questionnaire survey was conducted among firefighter training students (n = 186) and firefighters (n = 410), and a multivariate logistic regression analysis was performed to identify factors affecting the intention to participate in nuclear disaster activities. The percentage of students and firefighters who were willing to participate in nuclear disaster activities was 70.4% (n = 131) and 56.3% (n = 231) (P < 0.01), respectively. The factors affecting the students’ intention to participant were “wish to learn more information about radiation” and “firefighters should actively work in a nuclear disaster.” Meanwhile, the factors affecting the firefighters’ intention to work were “have self-confidence during nuclear disaster activities,” “participate if there is an incentive,” “unable to get a family member to understand the need to participate in a nuclear disaster activity,” and marital status. A student’s decision might be strongly connected to social norms about participating in nuclear disaster activities. The willingness to participate in nuclear disaster activities among firefighters might be improved by facilitating activities that can build their self-confidence, providing sufficient incentives, and helping their families understand their work. Therefore, not only direct education for responders but also educational activities for the general public and their families are essential.
Beaming as an explanation of the repetition/width relation in FRBs
Authors: Connor L , Miller M C , Gardenier D W
Published: July 2020

It is currently not known if repeating fast radio bursts (FRBs) are fundamentally different from those that have not been seen to repeat. One striking difference between repeaters and apparent non-repeaters in the Canadian Hydrogen Intensity Mapping Experiment sample is that the once-off events are typically shorter in duration than sources that have been detected two or more times. We offer a simple explanation for this discrepancy based on a selection effect due to beamed emission, in which highly beamed FRBs are less easily observed to repeat, but are abundant enough to detect often as once-off events. The explanation predicts that there is a continuous distribution of burst duration – not a static bimodal one – with a correlation between repetition rate and width. Pulse width and opening angle may be related by relativistic effects in shocks, where short-duration bursts have small solid angles due to a large common Lorentz factor. Alternatively, the relationship could be a geometric effect where narrow beams sweep past the observer more quickly, as with pulsars. Our model has implications for the FRB emission mechanism and energy scale, volumetric event rates, and the application of FRBs to cosmology.
Thermalization of large energy release in the early Universe
Authors: Chluba Jens , Ravenni Andrea , Acharya Sandeep Kumar
Published: July 2020

Spectral distortions of the cosmic microwave background (CMB) provide a unique tool for learning about the early phases of cosmic history, reaching deep into the primordial Universe. At redshifts z ≲ 106, thermalization processes become inefficient and existing limits from COBE/FIRAS imply that no more than Δρ/ρ ≲ 6 × 10−5 ($95{{\ \rm per\ cent}}$ c.l.) of energy could have been injected into the CMB. However, at higher redshifts, when thermalization is efficient, the constraint weakens and Δρ/ρ ≃ 0.01−0.1 could in principle have occurred. Existing computations for the evolution of distortions commonly assume Δρ/ρ ≪ 1 and thus become inaccurate in this case. Similarly, relativistic temperature corrections become relevant for large energy release, but have previously not been modelled as carefully. Here, we study the evolution of distortions and the thermalization process after single large energy release at z ≳ 105. We show that for large distortions the thermalization efficiency is significantly reduced and that the distortion visibility is sizeable to much earlier times. This tightens spectral distortions constraints on low-mass primordial black holes with masses $M_{\rm PBH}\lesssim 2 \times 10^{11}\, {\rm g}$. Similarly, distortion limits on the amplitude of the small-scale curvature power spectrum at wavenumbers $k\gtrsim 10^4\, {\rm Mpc}^{-1}$ and short-lived decaying particles with lifetimes $t_X\lesssim 10^7\, {\rm s}$ are tightened, however, these still require a more detailed time-dependent treatment. We also briefly discuss the constraints from measurements of the effective number of relativistic degrees of freedom and light element abundances and how these complement spectral distortion limits.
Management and Outcome of Left Ventricular Assist Device Infections in Patients Undergoing Cardiac Transplantation
Authors: Esquer Garrigos Zerelda , Castillo Almeida Natalia E , Gurram Pooja , Vijayvargiya Prakhar , Corsini Campioli Cristina G , Stulak John M , Rizza Stacey A , Baddour Larry M , Sohail M Rizwan
Published: July 2020

Background

Post-operative management of patients undergoing cardiac transplantation with an infected left ventricular assist device (LVAD) is unclear.

Methods

We retrospectively screened all adults with an LVAD who underwent cardiac transplantation at our institution from 2010 through 2018. We selected all cases of LVAD-specific and LVAD-related infections who were receiving antimicrobial therapy as initial treatment course or chronic suppression at the time of cardiac transplantation. Non-LVAD infections, superficial driveline-infection, or concurrent use of right ventricular assist device or extracorporeal membrane oxygenation device were excluded.

Results

A total of 54 cases met study criteria with 18/54 (33.6%) classified as LVAD- specific or related infections and 36/54 (66.6%) as non-infected. Cases of LVAD-infection had a higher median Charlson Comorbidity Index score at the time of transplantation compared to non-infected cases (P=.005). Of the 18 cases of infection, 13/18 (72.2%) were classified as LVAD-specific and 5/18 (27.8%) as LVAD-related. A total of 9/13 (69.2%) cases had proven LVAD-specific infections. Antimicrobial therapy was extended post-transplant to treat preceding LVAD-specific infection in all nine cases (9/13, 69.2%) with a median duration of 14 days (IQR 14-28). Following LVAD removal, antimicrobial treatment was not continued for preceding LVAD-related infections.

Conclusions

Patients with an LVAD-specific infection were treated with two weeks of pathogen-directed therapy post heart transplant without any relapses. For those without LVAD-specific infection or uncomplicated LVAD-related bacteremia who had completed antimicrobial therapy pre-transplant, antibiotics were discontinued after standard peri-operative prophylaxis and no relapses were observed.
Laser Interstitial Thermal Therapy in the Treatment of Thalamic Brain Tumors: A Case Series
Authors: Murayi Roger , Borghei-Razavi Hamid , Barnett Gene H , Mohammadi Alireza M
Published: July 2020

BACKGROUND

Surgical options for patients with thalamic brain tumors are limited. Traditional surgical resection is associated with a high degree of morbidity and mortality. Laser interstitial thermal therapy (LITT) utilizes a stereotactically placed laser probe to induce thermal damage to tumor tissue. LITT provides a surgical cytoreduction option for this challenging patient population. We present our experience treating thalamic brain tumors with LITT.

OBJECTIVE

To describe our experience and outcomes using LITT on patients with thalamic tumors.

METHODS

We analyzed 13 consecutive patients treated with LITT for thalamic tumors from 2012 to 2017. Radiographic, clinical characteristics, and outcome data were collected via review of electronic medical records

RESULTS

Thirteen patients with thalamic tumors were treated with LITT. Most had high-grade gliomas, including glioblastoma (n = 9) and anaplastic astrocytoma (n = 2). The average tumor volume was 12.0 cc and shrank by 42.9% at 3 mo. The average hospital stay was 3.0 d. Median ablation coverage as calculated by thermal damage threshold (TDT) lines was 98% and 95% for yellow (>43°C for >2 min) or blue (>10 min), respectively. Median disease-specific progression-free survival calculated for 8 patients in our cohort was 6.1 mo (range: 1.1-15.1 mo). There were 6 patients with perioperative morbidity and 2 perioperative deaths because of intracerebral hematoma.

CONCLUSION

LITT is a feasible treatment for patients with thalamic tumors. LITT offers a cytoreduction option in this challenging population. Patient selection is key. Close attention should be paid to lesion size to minimize morbidity. More studies comparing treatment modalities of thalamic tumors need to be performed.
Promoting Physical Activity via Telehealth in People With Parkinson Disease: The Path Forward After the COVID-19 Pandemic?
Authors: Quinn Lori , Macpherson Chelsea , Long Katrina , Shah Hiral
Published: July 2020

Objective

There is mounting evidence in support of exercise and physical activity as a first-line approach to managing symptoms and potentially altering disease progression in people with Parkinson disease (PD). For many patients, a critical gap is the need for expert guidance to overcome barriers, set realistic goals, and provide personalized advice to optimize exercise uptake and adherence. The purpose of this case report is to describe a physical activity coaching program (Engage-PD) for individuals newly diagnosed with PD and to highlight rapid modifications made to this program in response to the COVID-19 pandemic.

Methods (Case Description)

Engage-PD is a single cohort implementation study of a coaching intervention grounded in self-determination theory being conducted at Columbia University Parkinson’s Foundation Center of Excellence in New York City, NY (USA), the early epicenter of the COVID-19 pandemic in the United States. The project was uniquely positioned to be adapted to telehealth delivery and to address an immediate need for support and guidance in the home environment, including people with early-mid–stage PD. Participants completed baseline and follow-up (3 months) assessments and participated in up to 4 coaching sessions, all delivered via a telehealth platform. The intervention incorporated 1:1 coaching, goal-setting, physical activity monitoring, and use of a disease-specific workbook to promote and support safe exercise uptake.

Results

While the program is ongoing, 52 referrals were received and 27 individuals with PD enrolled in the first 2 months of the pandemic for a recruitment rate of 52%. Although direct comparisons with pre-coronavirus recruitment are difficult due to the recency of the Engage-PD implementation study, this recruitment rate was larger than expected, which may have been due to several factors (eg, most patients had limited, if any, access to in-person programs and therapy services during this time, so the Engage program filled an immediate need to provide exercise and activity guidance). There was a wide range of scores for both baseline physical activity and self-efficacy measures.

Conclusion

Remotely delivered interventions may serve as a sustainable platform for physical activity coaching programs for people with PD as well as other neurodegenerative diseases.

Impact

With the uncertainty brought about by the current pandemic, this case report highlights the opportunity to shift the current model of care for individuals with neurodegenerative diseases such as PD.
#GoingtotheFair: a social media listening analysis of agricultural fairs1
Authors: Mahoney Julie A , Widmar Nicole J O , Bir Courtney L
Published: July 2020

Agricultural fairs provide one of the last frontiers, and largest stages, for showcasing livestock agriculture to the public. However, public funding, attendance revenue, animal biosecurity, and public health concerns are all aspects worthy of conversation and increased research attention given the interaction between livestock animals and the general public in fair and festival settings. A prominent social media listening and data analytics platform was used to quantify online and social media chatter concerning agricultural fairs during a 27-mo period. A general search for online media referencing agricultural fair keywords was designed; social and online media mentions of agricultural fairs (n = 2,091,350 mentions) were further queried according to their reference to livestock, fair food, or the major agricultural product producing species of dairy and beef cattle (n = 68,900), poultry (n = 39,600), and swine (n = 31,250). Numbers of search results were found to be seasonal and Twitter was the single largest domain for all fair-related results; in contrast, the majority of livestock-related media was generated by news sources rather than from Twitter. On a weekly basis, the percentage of fair livestock mentions with species-specific reference was highly variable ranging from 0% to 86.8% for cattle, 0% to 85.7% for poultry, and 0% to 76.9% for swine. In addition to quantifying total search hits or mentions, the positivity/negativity of the search results was analyzed using natural language processing capabilities. The net sentiment quantified is the total percentage of positive posts minus the percentage of negative posts, which results in a necessarily bounded net sentiment between −100% and +100%. Overall net sentiment associated with mentions of agricultural fairs was positive; the topics garnering the highest positive sentiments were fair food and cattle (both 98% positive). Online discussion pertaining to agricultural fairs and swine was overall positive despite references to swine flu outbreaks. In conclusion, livestock and animal products had positive net sentiment over the time period studied, but there are multiple aspects of agricultural fairs worthy of further investigation and continued vigilance, including zoonotic disease risk and public perceptions of livestock industries.
Tree physiological monitoring of the 2018 larch budmoth outbreak: preference for leaf recovery and carbon storage over stem wood formation inLarix decidua
Authors: Peters Richard L , Miranda Jose Carlos , Schönbeck Leonie , Nievergelt Daniel , Fonti Marina V , Saurer Matthias , Stritih Ana , Fonti Patrick , Wermelinger Beat , von Arx Georg , Lehmann Marco M
Published: July 2020

Insect defoliation impacts forest productivity worldwide, highlighting the relevance of plant–insect interactions. The larch budmoth (Zeiraphera griseana Hübner) is one of the most extensively studied defoliators, where numerous tree ring-based analyses on its host (Larix decidua Mill.) have aided in identifying outbreak dynamics over the past millennia. Yet, outbreaks have been widely absent after the early 1980s, and little is known about the in situ tree physiological responses and the allocation of carbon resources during and after defoliation. In summer 2018, we tracked an ongoing larch budmoth outbreak in a well-studied larch forest in the Swiss Alps. We performed biweekly monitoring on an affected and unaffected site using a unique combination of xylogenesis observations, measurements of non-structural carbohydrates, isotopic analysis of needle assimilates and ground-based and remote-sensed leaf trait observations. The budmoth induced a defoliation that lasted 40 days and could be detected by satellite observations. Soluble sugars significantly decreased in needles and stem phloem of the defoliated trees, while starch levels remained stable in the stem and root xylem compared to the control. Carbon and oxygen isotope ratios in needle assimilates indicated that neither photosynthetic assimilation rates nor stomatal conductance was different between sites before, during and after the outbreak. Defoliated trees ceased cell wall thickening 17 days earlier than unaffected trees, showing the earliest halt of ring formation recorded from 2007 untill 2013 and causing significant thinner cell walls, particularly in the latewood. No significant differences were found for cell enlargement rates and ring width. Our study revealed that an outbreak causes a downregulation of cell wall thickening first, while no starch is mobilized or leaf physiology is adjusted to compensate for the reduced carbon source due to defoliation. Our observations suggest that affected larch trees prioritize leaf recovery and carbon storage over wood biomass development.
Rhizobial Microsymbionts of Kamchatka Oxytropis Species Possess Genes of the Type III and VI Secretion Systems, Which Can Affect the Development of Symbiosis
Authors: Safronova Vera I. , Guro Polina V. , Sazanova Anna L. , Kuznetsova Irina G. , Belimov Andrey A. , Yakubov Valentin V. , Chirak Elizaveta R. , Afonin Alexey М. , Gogolev Yuri V. , Andronov Evgeny E. , Tikhonovich Igor A.
Published: July 2020

A collection of rhizobial strains isolated from root nodules of the narrowly endemic legume species Oxytropis erecta, O. anadyrensis, O. kamtschatica, and O. pumilio originating from the Kamchatka Peninsula (Russian Federation) was obtained. Analysis of the 16S ribosomal RNA gene sequence showed a significant diversity of isolates belonging to families Rhizobiaceae (genus Rhizobium), Phyllobacteriaceae (genera Mesorhizobium, Phyllobacterium), and Bradyrhizobiaceae (genera Bosea, Tardiphaga). A plant nodulation assay showed that only strains belonging to genus Mesorhizobium could form nitrogen-fixing nodules on Oxytropis plants. The strains M. loti 582 and M. huakuii 583, in addition to symbiotic clusters, possessed genes of the type III and type VI secretion systems (T3SS and T6SS, respectively), which can influence the host specificity of strains. These strains formed nodules of two types (elongated and rounded) on O. kamtschatica roots. We suggest this phenomenon may result from Nod factor–dependent and –independent nodulation strategies. The obtained strains are of interest for further study of the T3SS and T6SS gene function and their role in the development of rhizobium-legume symbiosis. The prospects of using rhizobia having both gene systems related to symbiotic and nonsymbiotic nodulation strategies to enhance the efficiency of plant-microbe interactions by expanding the host specificity and increasing nodulation efficiency are discussed.
Safety in Pediatric Hospice and Palliative Care: A Qualitative Study
Authors: Pestian Teresa , Thienprayoon Rachel , Grossoehme Daniel , Friebert Sarah , Humphrey Lisa
Published: July 2020

Introduction:

Patient safety is extensively studied in both adults and pediatric medicine; however, knowledge is limited regarding particular safety events in pediatric hospice and palliative care (HPC). Additionally, pediatric HPC lacks a unified definition of safe care. This qualitative study sought to explore caregiver views regarding safe care in pediatric HPC.

Methods:

This is a secondary analysis of qualitative data from a multisite study utilizing semistructured interview data to evaluate parental perspectives of quality in pediatric home-based HPC programs across 3 different pediatric tertiary care hospitals. Eligible participants included parents and caregivers of children who were enrolled in a pediatric home-based hospice and palliative care program (HBHPC) from 2012 to 2016. The analysis was done using grounded theory methodology.

Results:

Forty-three parents participated in 39 interviews across all 3 sites; 19 families were bereaved. Responses to the prompt regarding safe care produced 8 unique domains encompassing parental definitions of safe care in pediatric HPC.

Discussion:

Parents of children in HPC programs describe “safe care” in novel ways, some of which echo Maslow’s hierarchy of needs. The use of traditional hospital safety measures for patients receiving HPC could undermine the patient’s goals or dignity, ultimately leading to harm to the patient.

Concluding summary:

Patients’ and families’ unique goals and values must be considered when defining safety for children in this population. Future studies should continue to explore family perspectives of safety in the hospital and ambulatory settings and seek to identify measurable indicators in safety which are truly patient- and family-centered.
Incorporating the Voice of Community Based Pediatricians to Improve Discharge Communication
Authors: Weiss Lindsay , Cooley Anthony , Orenstein Evan , Levy Matthew , Edmond Mary , Wong Emily , Hua Hannah , Hames Nicole
Published: July 2020

Introduction:

Communication between pediatric hospitalists and primary care physicians (PCPs) at discharge is an essential part of a successful transition to home. While many hospitals require communicating with PCPs for all admitted patients, it is unknown if PCPs find such communication valuable or if it improves outcomes. Our global aim was to improve discharge communication for patients that pediatric hospitalists and PCPs deemed appropriate.

Methods:

We sent surveys to 422 outpatient pediatricians in our care network to understand their communication preferences. Survey results informed local guidelines for when hospitalists should directly contact PCPs. We determined the proportion of inpatient discharges meeting those guidelines and set a target for our primary process metric: the proportion of discharges with attempted direct PCP contact. We engaged in Plan-Do-Study-Act cycles, including a discharge documentation tool in the electronic health record, education of inpatient teams, email reminders including group performance data, asynchronous Health Insurance Portability and Accountability Act-compliant messaging application, and competitions that shared blinded individual data.

Results:

We increased the percentage of documented direct communication with the PCPs from 2% to 33% and from 4% to 65% for those who met guidelines for direct communication.

Conclusions:

PCPs only want direct communication on a subset of discharges. Interventions focused on high-yield populations improved discharge communication in our institution.