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Abstract We develop a grand unified theory of matter and forces based on the gauge symmetry SU(5) L × SU(5) R with parity interchanging the two factor groups. Our main motivation for such a construction is to realize a minimal GUT embedding of left-right symmetric models that provide a parity solution to the strong CP problem without the axion. We show how the gauge couplings unify with an intermediate gauge symmetry SU(3) cL × SU(2)2L × U(1) L × SU(5) R , and establish its consistency with proton decay constraints. The model correctly reproduces the observed fermion masses and mixings and leads to naturally light Dirac neutrinos with their Yukawa couplings suppressed by a factor M I /M G , the ratio of the intermediate scale to the GUT scale. We call this mechanism type II-Dirac seesaw. Furthermore, the model predicts δ CP = ±(130.4±1.2)° and $${m}_{{\nu }_{1}}$$ = (4.8 – 8.4) meV for the Dirac CP phase and the lightest neutrino mass. We demonstrate how the model solves the strong CP problem via parity symmetry.

Abstract We study the prospects of probing neutrino mass models at the newly proposed antimuon collider $$\mu $$ μ TRISTAN, involving $$\mu ^+e^-$$ μ + e - scattering at $$\sqrt{s}= 346~\text {GeV}$$ s = 346 GeV and $$\mu ^+\mu ^+$$ μ + μ + scattering at $$\sqrt{s}= 2~\text {TeV}.$$ s = 2 TeV . We show that $$\mu $$ μ TRISTAN is uniquely sensitive to leptophilic neutral and doubly-charged scalars naturally occurring in various neutrino mass models, such as Zee, Zee–Babu, cocktail, and type-II seesaw models, over a wide range of mass and coupling values, well beyond the current experimental constraints. It also allows for the possibility to correlate the collider signals with neutrino mixing parameters and charged lepton flavor violating observables.

Abstract We study the low energy implications of a trinification model based on the gauge symmetry $$G= SU(3)_c \times SU(3)_L \times SU(3)_R$$ G = S U ( 3 ) c × S U ( 3 ) L × S U ( 3 ) R , without imposing gauge coupling unification. A minimal model requires two Higgs multiplets that reside in the bi-fundamental representation of G, and this is shown to be adequate for accommodating the Standard Model (SM) fermion masses and generate, via loop corrections and seesaw mechanism, suitable masses for the heavy neutral leptons as well as the observed SM neutrinos. We estimate a lower bound of around 15 TeV for the masses of the new down- type quarks that are required by the $$SU(3)_L \times SU(3)_R$$ S U ( 3 ) L × S U ( 3 ) R symmetry. We examine the resonant production at the LHC of the new gauge bosons, which leads to a lower bound of 16 TeV for the symmetry breaking scale of G. We also show how the muon $$g-2$$ g - 2 anomaly can be resolved in the presence of these new gauge bosons and the heavy charged leptons present in the model. Finally, the model predicts the presence of a topologically stable monopole carrying three quanta $$(6 \pi /e)$$ ( 6 π / e ) of Dirac magnetic charge and mass $$\gtrsim 160$$ ≳ 160 TeV. If new matter fields lying in the fundamental representations of G are included, the model predicts the presence of exotic leptons, mesons and baryons carrying fractional electric charges such as $$\pm e/3$$ ± e / 3 and $$\pm 2e/3$$ ± 2 e / 3 , fully compatible with the Dirac quantization condition.

The Zee model provides a simple model for one-loop Majorana neutrino masses. The new scalars can furthermore explain the long-standing deviation in the muon's magnetic moment and the recent CDF measurement of the W-boson mass. Together, these observations yield predictions for lepton flavor violating processes that are almost entirely testable in the near future. The remaining parameter space makes testable predictions for neutrino masses.

Abstract We develop a class of left-right symmetric theories based on the gauge group SU(3) c × SU(2) L × SU(2) R × U(1) with a generalized seesaw mechanism for generating the charged fermion masses. Neutrinos are naturally Dirac particles in this setup with their small masses arising from two-loop quantum corrections. We evaluate these two-loop diagrams exactly and analyze the flavor structure of the lepton sector. We find excellent fits to neutrino oscillation data, independent of the right-handed gauge symmetry breaking scale. We also explore the possibility that neutrinos are pseudo-Dirac particles in this framework, with the tiny mass splittings between active and sterile neutrinos arising from Planck-induced corrections and find possible realizations. These models can be tested in the near future with precision cosmological measurements of ∆N eff in CMB which is predicted to be ≃ 0.14. This class of models allows for a solution to the strong CP problem via parity symmetry without the need for an axion.

Abstract One of the most important discoveries in particle physics is the observation of nonzero neutrino masses, which dictates that the Standard Model (SM) is incomplete. Moreover, several pieces of evidence of lepton flavor universality violation (LFUV), gathered in the last few years, hint toward physics beyond the SM. TeV-scale scalar leptoquarks are the leading candidates for explaining these flavor anomalies in semileptonic charged and neutral current B-decays, the muon, and the electron magnetic dipole moments that can also participate in neutrino mass generation. In this work, we hypothesize that neutrino masses and LFUV have a common new physics origin and propose a new two-loop neutrino mass model that has the potential to resolve some of these flavor anomalies via leptoquarks and offers rich phenomenology. After deriving the neutrino mass formula for this newly-proposed model, we perform a detailed numerical analysis focusing on neutrino and charged lepton flavor violation phenomenology, where the latter provides stringent constraints on the Yukawa couplings and leptoquark masses. Finally, present and future bounds on the model’s parameter space are scrutinized with exemplified benchmark scenarios.

Abstract Experimental hints for lepton-flavor universality violation in the muon’s magnetic moment as well as neutral- and charged-current B-meson decays require Standard-Model extensions by particles such as leptoquarks that generically lead to unacceptably fast rates of charged lepton flavor violation and proton decay. We propose a model based on a gauged $$U(1)_{L_\mu -L_\tau }$$ U ( 1 ) L μ - L τ that eliminates all these unwanted decays by symmetry rather than finetuning and efficiently explains $$(g-2)_\mu $$ ( g - 2 ) μ , $$R_{K^{(*)}}$$ R K ( ∗ ) , $$R_{D^{(*)}}$$ R D ( ∗ ) , and neutrino masses. The $$U(1)_{L_\mu -L_\tau }$$ U ( 1 ) L μ - L τ furthermore acts as a stabilizing symmetry for dark matter and the light $$Z'$$ Z ′ gauge boson mediates velocity-dependent dark-matter self-interactions that resolve the small-scale structure problems. Lastly, even the Hubble tension can be ameliorated via the light $$Z'$$ Z ′ contribution to the relativistic degrees of freedom.

Abstract We explore parameter space in the Zee Model to resolve the long-standing tension of the electron and muon anomalous magnetic moment (AMM). The model comprises a second Higgs doublet and a charged singlet at electroweak scale and generates Majorana neutrino masses at one-loop level; the neutral partner of the SU(2) L doublet contributes to the AMM of electron and muon via one loop and two-loop corrections. We propose two minimal flavor structures that can explain these anomalies while fitting the neutrino oscillation data. We find that the neutral Higgs resides in the mass range of roughly 10–300 GeV or 1–30 GeV, depending on the flavor structures. The model is consistent with constraints from colliders, electroweak precision data, and lepton flavor violation. To be comprehensive, we examine the constraints from the electric dipole moment (EDM) and find a region of parameter space that gives a sizable contribution to muon EDM while simultaneously giving corrections to muon AMM. In addition to the light scalar, the two charged scalars with masses as low as 100 GeV can induce nonstandard neutrino interactions ε ee as large as 8%, potentially hinting at new physics. We also investigate the projected capability of future lepton colliders to probe the currently allowed parameter space consistent with both electron and muon AMMs via direct searches in the ℓ + ℓ − → ℓ + ℓ − (H → ℓ + ℓ − ) channel.

Motivated by the recently reported measurement of the W boson mass MW=80.4335±0.0094 GeV by the CDF collaboration, we propose a type III seesaw extension of the minimal supersymmetric standard model (MSSM) which also includes an R-parity violating term. Without taking potential SUSY radiative corrections into account, we show that the CDF measurement of MW and the LEP measurement of the ρ parameter can be simultaneously accommodated at the 2σ level. A long-lived gravitino in a few GeV mass range is a unique viable dark matter candidate in this framework.

Abstract We show how trinification models based on the gauge group SU(3) C × SU(3) L × SU(3) R realized near the TeV scale can provide naturally a variety of dark matter (DM) candidates. These models contain a discrete T parity which may remain unbroken even after spontaneous symmetry breaking. The lightest T-odd particle, which could be a fermion, a scalar, or a gauge boson, can constitute the dark matter of the universe. This framework naturally admits a doublet-singlet fermionic DM, a singlet scalar DM, or a vector boson DM. Here we develop the vector boson DM scenario wherein the DM couples off-diagonally with the usual fermions and vector-like fermions present in the theory. We show consistency of this framework with dark matter relic abundance and direct detection limits as well as LHC constraints. We derive upper limits of 900 GeV on the vector gauge boson DM mass and 4.5 TeV on the vector-like quark masses. We also show the consistency of spontaneous gauge symmetry breaking down to Standard Model times an extra U(1) while preserving the T-parity.

Abstract We present a model of radiative neutrino masses which also resolves anomalies reported in B-meson decays, R D ∗ $$ {R}_{D^{\left(\ast \right)}} $$ and R K ∗ $$ {R}_{K^{\left(\ast \right)}} $$ , as well as in muon g − 2 measurement, ∆a μ . Neutrino masses arise in the model through loop diagrams involving TeV-scale leptoquark (LQ) scalars R 2 and S 3. Fits to neutrino oscillation parameters are obtained satisfying all flavor constraints which also explain the anomalies in R D ∗ $$ {R}_{D^{\left(\ast \right)}} $$ , R K ∗ $$ {R}_{K^{\left(\ast \right)}} $$ and ∆a μ within 1 σ. An isospin-3/2 Higgs quadruplet plays a crucial role in generating neutrino masses; we point out that the doubly-charged scalar contained therein can be produced in the decays of the S 3 LQ, which enhances its reach to 1.1 (6.2) TeV at s $$ \sqrt{s} $$ = 14 TeV high-luminosity LHC ( s $$ \sqrt{s} $$ = 100 TeV FCC-hh). We also present flavor-dependent upper limits on the Yukawa couplings of the LQs to the first two family fermions, arising from non-resonant dilepton (pp → ℓ + ℓ − ) processes mediated by t-channel LQ exchange, which for 1 TeV LQ mass, are found to be in the range (0.15 − 0.36). These limits preclude any explanation of R D ∗ $$ {R}_{D^{\left(\ast \right)}} $$ through LQ-mediated B-meson decays involving ν e or ν μ in the final state. We also find that the same Yukawa couplings responsible for the chirally-enhanced contribution to ∆a μ give rise to new contributions to the SM Higgs decays to muon and tau pairs, with the modifications to the corresponding branching ratios being at (2–6)% level, which could be tested at future hadron colliders, such as HL-LHC and FCC-hh.

Abstract Models of radiative Majorana neutrino masses require new scalars and/or fermions to induce lepton-number-violating interactions. We show that these new particles also generate observable neutrino non-standard interactions (NSI) with matter. We classify radiative models as type-I or II, with type-I models containing at least one Standard Model (SM) particle inside the loop diagram generating neutrino mass, and type- II models having no SM particle inside the loop. While type-II radiative models do not generate NSI at tree-level, popular models which fall under the type-I category are shown, somewhat surprisingly, to generate observable NSI at tree-level, while being consistent with direct and indirect constraints from colliders, electroweak precision data and charged-lepton flavor violation (cLFV). We survey such models where neutrino masses arise at one, two and three loops. In the prototypical Zee model which generates neutrino masses via one-loop diagrams involving charged scalars, we find that diagonal NSI can be as large as (8%, 3.8%, 9.3%) for (ε ee , ε μμ , ε ττ ), while off-diagonal NSI can be at most (10 −3%, 0.56%, 0.34%) for (ε eμ , ε eτ , ε μτ ). In one-loop neutrino mass models using leptoquarks (LQs), (ε μμ , ε ττ ) can be as large as (21.6%, 51.7%), while ε ee and (ε eμ , ε eτ , ε μτ ) can at most be 0.6%. Other two- and three-loop LQ models are found to give NSI of similar strength. The most stringent constraints on the diagonal NSI are found to come from neutrino oscillation and scattering experiments, while the off-diagonal NSI are mostly constrained by low-energy processes, such as atomic parity violation and cLFV. We also comment on the future sensitivity of these radiative models in long-baseline neutrino experiments, such as DUNE. While our analysis is focused on radiative neutrino mass models, it essentially covers all NSI possibilities with heavy mediators.

Arsenic is highly toxic and carcinogenic element that mainly enters into our body through drinking water and caused adverse effect even at low concentration. A new type of cation exchanger is developed from waste biomass of watermelon rind after increasing the carboxyl functional groups by saponification. Saponified Watermelon Rind (SWR) was further loaded with La(III) to attenuate the contamination of As(III) from water. Characterization of biosorbent was performed using Fourier Transform Infra-Red (FTIR) spectroscopy, Field emission Scanning Electron Microscopy (Fe-SEM,) Energy Dispersive X-ray (EDX) spectroscopy and zeta potential analysis. Arsenic speciation of sorption product through X-ray photoelectron spectroscopic (XPS) analysis revealed that As(III) is partially converted into As(V) during biosorption process. The biosorption tests for As(III) were explored under different operating conditions. La(III)-SWR towards As(III) biosorption was best described by Langmuir biosorption isotherm and pseudo second order kinetic model. At a pH of 12.08, the optimum biosorption capacity was found to be 37.73 ± 0.12, 48.78 ± 0.09, 62.50 ± 0.11 mg/g, respectively at temperatures 298 K, 303 K and 308 K. The existance of chloride and nitrate showed negligible interference whereas sulphate and phosphate significantly inhibits As(III) biosorption. Thermodynamic study showed spontaneous and endothermic nature As(III) biosorption onto La(III)-SWR. The sorbed As(III) was eluted almost completely using 2 M NaOH. The findings of this study insinuated that La(III)-SWR biosorbent investigated in this study can be a low cost, environmentally benign and eco-friendly material for the treatment of aqueous solution polluted with arsenic ions.

BackgroundWorldwide tuberculosis (TB) takes more lives than any other infectious diseases. WHO estimates around 68,000 incident TB cases in Nepal. However, in 2018 only around 27,232 new TB cases were reported in the national system, resulting around 40,768 incident TB cases missing every year in Nepal. National Tuberculosis Control Center carried out this study in anti-retroviral therapy (ART) sites to estimate the prevalence of TB and identify the associated risk factors for TB among the people living with Human Immunodeficiency Virus (PLHIVs) in Nepal.MethodsIt was a cross-sectional institution-based study conducted between March and August 2018. Six ART sites with high caseloads of PLHIVs were selected. PLHIVs who were equal or above 18 years of age and were in ART program at the selected study sites were considered eligible for the study. Diagnosis of tuberculosis among PLHIVs who agreed to participate in the study was carried out as per the National Tuberculosis Management Guideline of National Tuberculosis Program of Nepal.ResultsAmong 403 PLHIVs, tuberculosis was diagnosed in 40 (9.9%) individuals. Median age of the participants was 36 (30-43) years. Prevalence of TB was significantly higher among male PLHIVs than female PLHIVs (13.6% Vs 5.8%; P = 0.02) and Dalit ethnic group compared to Brahmin/Chettri (22.0%Vs5.9%, P = 0.01). The risk of developing TB was found significant among those with HIV stage progressed to WHO stage 3 and 4 (OR = 4.85, PConclusionsPrevalence of TB among PLHIVs in Nepal was found 9.9%. Risk of developing TB was higher among PLHIVs who were male, Dalit, with HIV stage progressed to WHO stage 3 and 4 and with family history of TB. Hence, targeted interventions are needed to prevent the risk of developing TB among PLHIVs. Similarly, integrated, and comprehensive TB and HIV diagnosis and treatment services are needed for the management of TB/HIV co-infection in Nepal.

Abstract Background The World Health Organization (WHO) End TB Strategy has established a milestone to reduce the number of tuberculosis (TB)- affected households facing catastrophic costs to zero by 2020. The role of active case finding (ACF) in reducing patient costs has not been determined globally. This study therefore aimed to compare costs incurred by TB patients diagnosed through ACF and passive case finding (PCF), and to determine the prevalence and intensity of patient-incurred catastrophic costs in Nepal. Methods The study was conducted in two districts of Nepal: Bardiya and Pyuthan (Province No. 5) between June and August 2018. One hundred patients were included in this study in a 1:1 ratio (PCF: ACF, 25 consecutive ACF and 25 consecutive PCF patients in each district). The WHO TB patient costing tool was applied to collect information from patients or a member of their family regarding indirect and direct medical and non-medical costs. Catastrophic costs were calculated based on the proportion of patients with total costs exceeding 20% of their annual household income. The intensity of catastrophic costs was calculated using the positive overshoot method. The chi-square and Wilcoxon-Mann-Whitney tests were used to compare proportions and costs. Meanwhile, the Mantel Haenszel test was performed to assess the association between catastrophic costs and type of diagnosis. Results Ninety-nine patients were interviewed (50 ACF and 49 PCF). Patients diagnosed through ACF incurred lower costs during the pre-treatment period (direct medical: USD 14 vs USD 32, P = 0.001; direct non-medical: USD 3 vs USD 10, P = 0.004; indirect, time loss: USD 4 vs USD 13, P

BackgroundIn the last decade, active case finding (ACF) strategies for tuberculosis (TB) have been implemented in many diverse settings, with some showing large increases in case detection and reporting at the sub-national level. There have also been several studies which seek to provide evidence for the benefits of ACF to individuals and communities in the broader context. However, there remains no quantification of the impact of ACF with regards to reducing the burden of transmission. We sought to address this knowledge gap and quantify the potential impact of active case finding on reducing transmission of TB at the national scale and further, to determine the intensification of intervention efforts required to bring the reproduction number (R0) below 1 for TB.MethodsWe adopt a dynamic transmission model that incorporates heterogeneity in risk to TB to assess the impact of an ACF programme (IMPACT TB) on reducing TB incidence in Vietnam and Nepal. We fit the models to country-level incidence data using a Bayesian Markov Chain Monte Carlo approach. We assess the impact of ACF using a parameter in our model, which we term the treatment success rate. Using programmatic data, we estimate how much this parameter has increased as a result of IMPACT TB in the implementation districts of Vietnam and Nepal and quantify additional efforts needed to eliminate transmission of TB in these countries by 2035.ResultsExtending the IMPACT TB programme to national coverage would lead to moderate decreases in TB incidence and would not be enough to interrupt transmission by 2035. Decreasing transmission sufficiently to bring the reproduction number (R0) below 1, would require a further intensification of current efforts, even at the sub-national level.ConclusionsActive case finding programmes are effective in reducing TB in the short term. However, interruption of transmission in high-burden countries, like Vietnam and Nepal, will require comprehensive incremental efforts. Complementary measures to reduce progression from infection to disease, and reactivation of latent infection, are needed to meet the WHO End TB incidence targets.

This study compared the yield of tuberculosis (TB) active case finding (ACF) interventions applied under TB REACH funding. Between June 2017 to November 2018, Birat Nepal Medical Trust identified presumptive cases using simple verbal screening from three interventions: door-to-door screening of social contacts of known index cases, TB camps in remote areas, and screening for hospital out-patient department (OPD) attendees. Symptomatic individuals were then tested using smear microscopy or GeneXpert MTB/RIF as first diagnostic test. Yield rates were compared for each intervention and diagnostic method. We evaluated additional cases notified from ACF interventions by comparing case notifications of the intervention and control districts using standard TB REACH methodology. The project identified 1092 TB cases. The highest yield was obtained from OPD screening at hospitals (n = 566/1092; 52%). The proportion of positive tests using GeneXpert (5.5%, n = 859/15,637) was significantly higher than from microscopy testing 2% (n = 120/6309). (OR = 1.4; 95%CI = 1.12–1.72; p = 0.0026). The project achieved 29% additionality in case notifications in the intervention districts demonstrating that GeneXpert achieved substantially higher case-finding yields. Therefore, to increase national case notification for TB, Nepal should integrate OPD screening using GeneXpert testing in every district hospital and scale up of community-based ACF of TB patient contacts nationally.

BACKGROUND AND OBJECTIVES:People receiving treatment for multidrug-resistant tuberculosis (MDR-TB) have high rates of depression. Psychosocial support in general, and treatments for depression in particular, form an important but neglected area of patient-centred care, and a key pillar in the global End TB strategy. We assessed the feasibility and acceptability of a psychosocial support package for people receiving treatment for MDR-TB in Nepal. METHODS:This feasibility study used a mixed quantitative and qualitative approach. We implemented the intervention package in two National Tuberculosis Programme (NTP) MDR-TB treatment centres and 8 sub-centres. We screened patients monthly for depression and anxiety (cut-off ≥24 and ≥17 respectively on the Hopkins Symptom Checklist) and also for low social support (cut-off ≤3 on the Multidimensional Scale of Perceived Social Support). Those who screened positive on either screening tool received the Healthy Activity Program (HAP), which uses brief counselling based on behavioural activation theory. Other aspects of the psychosocial package were information/education materials and group interactions with other patients. RESULTS:We screened 135 patients, of whom 12 (9%) received HAP counselling, 115 (85%) received information materials, 80 (59%) received an education session and 49 (36%) received at least one group session. Eight group sessions were conducted in total. All aspects of the intervention package were acceptable to patients, including the screening, information, group work and counselling. Patients particularly valued having someone to talk to about their concerns and worries. We were able to successfully train individuals with no experience of psychological counselling to deliver HAP. CONCLUSION:This psychosocial support package is acceptable to patients. The information materials we developed are feasible to deliver in the current NTP. However, the structured psychological counselling (HAP), is not feasible in the current NTP due to time constraints. This requires additional investment of counsellors in TB clinics.

Previous studies investigating the design of synthetic bladder wall substitutes have involved polymers with micro dimensional structures. Since the body is made up of nano-structured components (e.g., extracellular matrix proteins), the focus of the present in vitro study was to design nano-structured polymers for use as synthetic bladder constructs that mimic the topography of natural bladder tissue. In order to complete this task, novel nano-structured biodegradable polymeric films of poly-lactic-co-glycolic-acid (PLGA), poly-ether-urethane (PU), and poly-caprolactone (PCL) were fabricated and separately treated with various concentrations of NaOH (for PLGA and PCL) and HNO3 (for PU) for select time periods. These treatments reduced the polymer surface feature dimensions from conventional micron dimensions to biologically inspired nanometer dimensions. Select cytocompatibility properties of these biomaterials were tested in vitro. Results provide the first evidence that adhesion of bladder smooth muscle cells is enhanced as polymer surface feature dimensions are reduced into the nanometer range. In addition, surface analysis results reveal that the polymer nanometer surface roughness is the primary design parameter that increases bladder smooth muscle cell adhesion. For this reason, the “next generation” of tissue-engineered bladder constructs with increased efficacy should contain surfaces with nanometer (as opposed to micron) surface features. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 1374–1383, 2003 [ABSTRACT FROM AUTHOR]

This report summarizes the present status of neutrino non-standard interactions (NSI). After a brief overview, several aspects of NSIs are discussed, including connection to neutrino mass models, model-building and phenomenology of large NSI with both light and heavy mediators, NSI phenomenology in both short- and long-baseline neutrino oscillation experiments, neutrino cross-sections, complementarity of NSI with other low- and high-energy experiments, fits with neutrino oscillation and scattering data, DUNE sensitivity to NSI, effective field theory of NSI, as well as the relevance of NSI to dark matter and cosmology. We also discuss the open questions and interesting future directions that can be pursued by the community at large. This report is based on talks and discussions during the Neutrino Theory Network NSI workshop held at Washington University in St. Louis from May 29-31, 2019 (https://indico.cern.ch/event/812851/)