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GPR55 controls functional differentiation of self-renewing epithelial progenitors for salivation

Author: Korchynska S
Lutz M I
Borók E
Pammer J
Cinquina V
Fedirko N
Irving A J
Mackie Ken
Harkany T
Keimpema E
Publication venue
Publication date: 2020
Field of study

GPR55, a lipid-sensing receptor, is implicated in cell cycle control, malignant cell mobilization, and tissue invasion in cancer. However, a physiological role for GPR55 is virtually unknown for any tissue type. Here, we localize GPR55 to self-renewing ductal epithelial cells and their terminally differentiated progeny in both human and mouse salivary glands. Moreover, we find GPR55 expression downregulated in salivary gland mucoepidermoid carcinomas and GPR55 reinstatement by antitumor irradiation, suggesting that GPR55 controls renegade proliferation. Indeed, GPR55 antagonism increases cell proliferation and function determination in quasiphysiological systems. In addition,

Gpr55^{–/–}

mice present ~50% enlarged submandibular glands with many more granulated ducts, as well as disordered endoplasmic reticuli and with glycoprotein content. Next, we hypothesized that GPR55 could also modulate salivation and glycoprotein content by entraining differentiated excretory progeny. Accordingly, GPR55 activation facilitated glycoprotein release by itself, inducing low-amplitude Ca

^{2+}

oscillations, as well as enhancing acetylcholine-induced Ca

^{2+}

responses. Topical application of GPR55 agonists, which are ineffective in

Gpr55^{–/–}

mice, into adult rodent submandibular glands increased salivation and saliva glycoprotein content. Overall, we propose that GPR55 signaling in epithelial cells ensures both the life-long renewal of ductal cells and the continuous availability of saliva and glycoproteins for oral health and food intake

Editorial: Enhancing quantitative theory-testing entrepreneurship research

Author: Anderson Brian S.
Wennberg Karl
McMullen Jeffery S.
Publication venue
Publication date: 2020
Field of study

The purpose of this editorial is to discuss methodological advancements to enhance quantitative theory-testing entrepreneurship research. As the impact of entrepreneurship scholarship accelerates and deepens, our methods must keep pace to continue shaping theory, policy, and practice. Like our sister fields in business, entrepreneurship is coming to terms with the replication and credibility crisis in the social sciences, forcing the field to revisit commonly-held assumptions that limit the promise and prospect of our scholarship. Thus, we provide suggestions for reviewers and editors to identify concerns in empirical work, and to guide authors in improving their analyses and research designs. We hope that our editorial provides useful and actionable guidance for entrepreneurship researchers submitting theory-testing papers to Journal of Business Venturing

Measurement of $\mathcal{B}(J/\psi \to \eta' e^+ e^-)$ and search for a dark photon

Author: Ablikim M.
Mitchell R. E., et al.
Publication venue
Publication date: 2020
Field of study

Using a data sample of

(1310.6±7.0)×10^6 J/\psi

decay events collected with the BESIII detector at BEPCII, we study the electromagnetic Dalitz decay

J/\psi \to \eta' e^+e^-

with two dominant

\eta'

decay modes,

\eta' \to \gamma \pi^+ \pi^-

and

\eta' \to \pi^+\pi^-\eta

. The branching fraction is determined to be

\mathcal{B}(J/\psi \to \eta' e^+e^-) = (6.59\pm0.07\pm0.17) \times 10^{-5}

, which improves in precision by a factor of 2 over the previous BESIII measurement. A search for the dark photon

(\gamma ')

is performed via

J/\psi \to\eta' \gamma ', \gamma' \to e^{+}e^{-}

. Excluding the

\omega

and

\phi

mass regions, no significant signal is observed in the mass range from 0.1 to 2.1 GeV/

c^2

. We set upper limits at the 90% confidence level on

\mathcal{B}(J/\psi \to \eta' \gamma ')\times\mathcal{B}(\gamma ' \to e^+e^-)

\mathcal{B}(J/\psi \to\eta' \gamma'

and the mixing strength as a function of dark photon mass. This is among the first searches for dark photons in charmonium decays

Measurement of $e^{+} e^{-} \rightarrow K^{+} K^{-}$ cross section at $\sqrt{s} = 2.00 - 3.08$ GeV

Author: Ablikim M.
Mitchell R. E., et al.
Publication venue
Publication date: 2020
Field of study

The cross section of the process

e^{+} e^{-} \rightarrow K^{+} K^{-}

is measured at a number of center-of-mass energies

\sqrt{s}

from 2.00 to 3.08 GeV with the BESIII detector at the Beijing Electron Positron Collider (BEPCII). The results provide the best precision achieved so far. A resonant structure around 2.2 GeV is observed in the cross section line shape. A Breit-Wigner fit yields a mass of

M=2239.2 \pm 7.1 \pm 11.3

~ and a width of

\Gamma=139.8\pm12.3\pm20.6

MeV, where the first uncertainties are statistical and the second ones are systematic. In addition, the time-like electromagnetic form factor of the kaon is determined at the individual center-of-mass energy points

Measurement of the Dynamics of the Decays $D_s^+ \rightarrow \eta^{(\prime)} e^+ \nu_e$

Author: Ablikim M.
Mitchell R. E., et al.
Publication venue
Publication date: 2020
Field of study

Using

e^+e^−

annihilation data corresponding to an integrated luminosity of 3.19 fb

^{−1}

collected at a center-of-mass energy of 4.178 GeV with the BESIII detector, we measure the absolute branching fractions

\mathcal{B}_{D_s^+ \rightarrow \eta e^{+} \nu_e }

(2.323\pm0.063_{\rm stat}\pm0.063_{\rm syst})\%

and

\mathcal{B}_{D_s^+ \rightarrow \eta^{\prime} e^{+} \nu_e}

(0.824\pm0.073_{\rm stat}\pm0.027_{\rm syst})\%

via a tagged analysis technique, where one

D_s

is fully reconstructed in a hadronic mode. Combining these measurements with previous BESIII measurements of

\mathcal{B}_{D^+\to\eta^{(\prime)} e^{+} \nu_e}

, the

\eta-\eta^\prime

mixing angle in the quark flavour basis is determined to be

\phi_{\rm P} = (40.1\pm2.1_{\rm stat}\pm0.7_{\rm syst})^\circ

. From the first measurements of the dynamics of

D^+_s\to \eta^{(\prime)}e^+\nu_e

decays, the products of the hadronic form factors

f_+^{\eta^{(\prime)}}(0)

and the Cabibbo-Kobayashi-Maskawa matrix element

|V_{cs}|

are determined with different form factor parameterizations. For the two-parameter series expansion, the results are

f^{\eta}_+(0)|V_{cs}| = 0.4455\pm0.0053_{\rm stat}\pm0.0044_{\rm syst}

and

f^{\eta^{\prime}}_+(0)|V_{cs}| = 0.477\pm0.049_{\rm stat}\pm0.011_{\rm syst}

Observation of $\eta_c\to\omega\omega$ in $J/\psi\to\gamma\omega\omega$

Author: Ablikim M.
Mitchell R. E., et al.
Publication venue
Publication date: 2020
Field of study

Using a sample of

(1310.6±7.0)×10^6

J/\psi

events recorded with the BESIII detector at the symmetric electron positron collider BEPCII, we report the observation of the decay of the

(1^1 S_0)

charmonium state

\eta_c

into a pair of

\omega

mesons in the process

J/\psi\to\gamma\omega\omega

. The branching fraction is measured for the first time to be

\mathcal{B}(\eta_c\to\omega\omega)= (2.88\pm0.10\pm0.46\pm0.68)\times10^{-3}

, where the first uncertainty is statistical, the second systematic and the third is from the uncertainty of

\mathcal{B}(J/\psi\to\gamma\eta_c)

. The mass and width of the

\eta_c

are determined as

M=(2985.9\pm0.7\pm2.1)\,

MeV/

c^2

and

\Gamma=(33.8\pm1.6\pm4.1)\,

MeV

Study of the $D^0\to K^-\mu^+\nu_\mu$ dynamics and test of lepton flavor universality with $D^0\to K^-\ell^+\nu_\ell$ decays

Author: Ablikim M.
Mitchell R. E., et al.
Publication venue
Publication date: 2020
Field of study

Using

e^+e^−

annihilation data of 2.93 fb

^{−1}

collected at center-of-mass energy

\sqrt{s}

= 3.773 GeV with the BESIII detector, we measure the absolute branching fraction of

D^{0}\to K^{-}\mu^{+}\nu_{\mu}

with significantly improved precision:

{\mathcal B}_{D^{0}\to K^{-}\mu^{+}\nu_{\mu}}=(3.413\pm0.019_{\rm stat.}\pm0.035_{\rm syst.})\%

. Combining with our previous measurement of

{\mathcal B}_{D^0\to K^-e^+\nu_e}

, the ratio of the two branching fractions is determined to be

{\mathcal B}_{D^0\to K^-\mu^+\nu_\mu}/{\mathcal B}_{D^0\to K^-e^+\nu_e}=0.974\pm0.007_{\rm stat.}\pm0.012_{\rm syst.}

, which agrees with the theoretical expectation of lepton flavor universality within the uncertainty. A study of the ratio of the two branching fractions in different four-momentum transfer regions is also performed, and no evidence for lepton flavor universality violation is found with current statistics. Taking inputs from global fit in the standard model and lattice quantum chromodynamics separately, we determine

f_{+}^{K}(0)=0.7327\pm0.0039_{\rm stat.}\pm0.0030_{\rm syst.}

and

|V_{cs}| = 0.955\pm0.005_{\rm stat.}\pm0.004_{\rm syst.}\pm0.024_{\rm LQCD}

(Re)Framing Resistance to Culturally Relevant Education as a Multilevel Learning Problem

Author: Neri Rebecca Colina
Lozano Maritza
Gomez Louis M
Publication venue
Publication date: 2020
Field of study

Despite evidence of promise, the adoption of culturally relevant educational (CRE) approaches to teaching and learning remains sporadic and underwhelming. In this chapter, we question this state of affairs by investigating teacher resistance to CRE. Through our examination of the literature, we have come to understand teacher resistance to CRE as a multilevel learning problem that stems from (a) limited understanding and belief in the efficacy of CRE and (b) a lack of know-how needed to execute it. We therefore characterize resistance as a learning problem, rather than a problem of individual compliance, and view contextual variation in its take up as an opportunity to learn. Framing teacher resistance to CRE as a multilevel learning problem provides a way forward by shifting the perception of resistance as simply negative to an understanding of resistance as a diagnostic tool, or warning signal about when, where, for whom, and why a change can be particularly difficult. By representing our review of the literature as a problem space map, we offer a tool that can be used to pinpoint, anticipate, and preemptively address the multilevel factors that contribute to teachers’ resistance to CRE

Zika knowledge and prevention practices among U.S. travelers: a large cross-sectional survey study

Author: Luetke M
Omodior Oghenekaro
Nelson Erik John
Publication venue
Publication date: 2020
Field of study

Background: The aim of this study was to investigate what factors predict knowledge about Zika transmission, symptomology, and treatment among U.S. travelers and, additionally, to evaluate how Zika knowledge influences the adoption of personal protective behaviors. Methods: Data were collected as part of a cross-sectional survey study using a probability-based internet panel of U.S. travelers in June 2017. We ran logistic regression models of factors predicting Zika knowledge (high vs. low) and of knowledge predicting adoption of personal protective measures. Results: We found that traveling to a Zika endemic country and travelers’ gender were both significantly predictive of higher Zika knowledge (odds ratio (OR): 1.48, 95% confidence interval (CI): 1.14–1.93 and OR: 1.44, 95% CI: 1.08–1.92), adjusting for age, race, education, income, and trip purpose. Additionally, among travelers to Zika endemic countries, individuals with higher Zika knowledge had significantly higher odds of engaging in preventive behaviors compared to those with lower knowledge. However, few travelers knew about the sexual transmission of Zika and adopted sexual prevention measures. Conclusions: Our findings suggest that there are gaps in knowledge about the risks and transmission of Zika and travelers with low knowledge are less likely to engage in the appropriate prevention methods. Significantly, few U.S. travelers have knowledge of the sexual transmission of Zika and, accordingly, there is less overall engagement with prevention measures for this transmission mechanism than for vector-borne transmission

Phase transitions in the Zp and U(1) clock models

Author: Sun G.
Vekua T.
Cobanera E.
Ortiz G.
Publication venue
Publication date: 2020
Field of study

Quantum phase transitions are studied in the nonchiral -clock chain, and a new explicitly U(1)-symmetric clock model, by monitoring the ground-state fidelity susceptibility. For ≥ 5 , the self-dual Z -symmetric chain displays a double-hump structure in the fidelity susceptibility with both peak positions and heights scaling logarithmically to their corresponding thermodynamic values. This scaling is precisely as expected for two Beresinskii-Kosterlitz-Thouless (BKT) transitions located symmetrically about the self-dual point, and so confirms numerically the theoretical scenario that sets = 5 as the lowest supporting BKT transitions in Z -symmetric clock models. For our U(1)-symmetric, non-self-dual minimal modification of the -clock model we find that the phase diagram depends strongly on the parity of and only one BKT transition survives for ≥ 5 . Using asymptotic calculus we map the self-dual clock model exactly, in the large limit, to the quantum ( 2 ) rotor chain. Finally, using bond-algebraic dualities we estimate the critical BKT transition temperatures of the classical planar -clock models defined on square lattices, in the limit of extreme spatial anisotropy. Our values agree remarkably well with those determined via classical Monte Carlo for isotropic lattices. This work highlights the power of the fidelity susceptibility as a tool for diagnosing the BKT transitions even when only discrete symmetries are present

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