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Wavelength selection in the twist buckling of pre-strained elastic ribbons
No full textInternational audienceA competition between short- and long-wavelength twist buckling instabilities has been reported in experiments on thin elastic ribbons having pre-strain concentrated in a rectangular region surrounding the axis. The wavelength of the twisting mode has been reported to either scale (i) as the width of the ribbon when the pre-strain is large (short-wavelength case) or (ii) as the length of the ribbon when the pre-strain is small (large-wavelength case). Existing one-dimensional rod or ribbon models can only account for large-wavelength buckling. We derive a novel one-dimensional model that accounts for short-wavelength buckling as well. It is derived from non-linear shell theory by dimension reduction and captures in an asymptotically correct way both the non-convex dependence of the strain energy on the twisting strain~ (which causes buckling in a first place) and its dependence on the strain gradient . The competition between short- and long-wavelength buckling is shown to be governed by the sign of the incremental elastic modulus associated with the twist gradient . The one-dimensional model reproduces the main features of equilibrium configurations generated in earlier work using 3D finite-element simulations. In passing, we introduce a novel truncation strategy applicable to higher-order dimension reduction, that preserves positiveness of the strain energy even when the gradient modulus is negative
Search for rare decays of the Z and Higgs bosons to a J/ or (2S) meson and a photon in proton-proton collisions at = 13 TeV
No full textInternational audienceA search is presented for rare decays of the Z and Higgs bosons to a photon and a J/ or a (2S) meson, with the charmonium state subsequentially decaying to a pair of muons. The data set corresponds to an integrated luminosity of 123 fb of proton-proton collisions at a center-of-mass energy of 13 TeV collected with the CMS detector at the LHC. No evidence for branching fractions of these rare decay channels larger than predicted in the standard model is observed. Upper limits at 95% confidence level are set: (H J/) 2.6 10, (H (2S)) 9.9 10, (Z J/) 0.6 10, and (Z(2S)) 1.3 10. The ratio of the Higgs boson coupling modifiers is constrained to be in the interval (157, 199) at 95% confidence level. Assuming , this interval becomes (166, 208)
Characterization of photophysical and electrochemical properties of a PNDT-T-DPP dye-based polymer with highly planar features and development of organic electronic applications
No full textInternational audienceCommon organic small molecule dyes exhibit chemical modifiability and are easy to polymerize, making them potential monomers in organic electronics. The multifunctionality of organic synthetic chemistry allows for material adaptability. Here, we report the synthesis route and purification methods for dye polymer based on thiophene-diketopyrrolopyrrole. Their orderly conjugated structure and high coplanarity contribute to a high crystallinity, which is favorable for charge carrier transport. By adjusting the device structure and thin film preparation conditions, the hole transport properties of the materials were further optimized, achieving a maximum mobility of up to 0.35 cm 2 V -1 s -1 . The excellent charge carrier performance reveals the potential of such materials for applications in organic electronics
A continuum magneto-viscoelastic model for isotropic soft magnetorheological elastomers: experiments, theory and numerical implementation
No full textInternational audienceThis study deals with the experimental, theoretical and numerical investigation of the nonlinear viscoelastic response of magnetically soft magnetorheological elastomers (commonly known as -MREs and denoted here simply as MREs) subjected to combined magnetic and simple shear loads. We consider a fairly soft mechanically MRE. The experiments show a strong effect of the magnetic field on the resulting viscosity and hence dissipated energy expanded by the material during a simple shear cycle. Moreover, the effect of frequency on the response is weak indicating strongly nonlinear viscous effects similar to non-Newtonian fluids. An analytical magneto-viscoelastic model is proposed exhibiting magneto-mechanical coupling at both equilibrium and non-equilibrium energies as well as on the dissipation potential. The model is calibrated by solving in a semi-analytical way a simplified boundary value problem (BVP) of an infinite thin MRE strip embedded in an infinite air domain. These simplified solutions are cross-validated by full-field finite element simulations of the experimental setup showing very good agreement between the experimental data and model estimates. This illustrates the validity of the simplified material model for the proposed experimental setup and sets the ground for a more universal experimental protocol to characterize properly the finite strain response of MREs more generally
Measurement of the Higgs boson mass and width using the four-lepton final state in proton-proton collisions at = 13 TeV
No full textInternational audienceA measurement of the Higgs boson mass and width via its decay to two Z bosons is presented. Proton-proton collision data collected by the CMS experiment, corresponding to an integrated luminosity of 138 fb at a center-of-mass energy of 13 TeV is used. The invariant mass distribution of four leptons in the on-shell Higgs boson decay is used to measure its mass and contrain its width. This yields the most precise single measurement of the Higgs boson mass to date, 125.04 0.12 GeV, and an upper limit on the width 330 MeV at 95% confidence level. A combination of the on- and off-shell Higgs boson production decaying to four leptons is used to determine the Higgs boson width, assuming that no new virtual particles affect the production, a premise that is tested by adding new heavy particles in the gluon fusion loop model. This result is combined with a previous CMS analysis of the off-shell Higgs boson production with decay to two leptons and two neutrinos, giving a measured Higgs boson width of 3.0 MeV, in agreement with the standard model prediction of 4.1 MeV. The strength of the off-shell Higgs boson production is also reported. The scenario of no off-shell Higgs boson production is excluded at a confidence level corresponding to 3.8 standard deviations
Narok County Fiscal Srategy Paper 2025
Get PDFThe 2025 County Fiscal Strategy Paper (CFSP) is the third to be prepared under the new administration. it reaffirms the governor's priority programmes, policies, and reforms as set out in the third generation CIDP 2023-2027. The 2025 CFSP comes at a time when the county is implementing its third year of the County Integrated Development Plan (CIDP 2023-2027), which will prioritize implementation of economic recovery strategies of the new administration to reposition the county on a steady and sustainable growth trajectory. This paper has been prepared against a backdrop of stable global and domestic economic outlook. Global growth is projected at 3.2% in 2024 and 3.3 % in 2025 from 3.3% in 2023. The outlook reflects economic recovery in China, Euro area and UK despite a slowdown in activity in the USA and Japan. On the Domestic front, the Kenyan economy has remained resilient despite the challenging domestic and external environmen
Trans Nzoia County Fiscal Strategy Paper 2025
Get PDFThe County Fiscal Strategy Paper (CFSP) for 2025 has been prepared in accordance with the PFM Act 2012, marking the transition from the strategic to the operational phase of budget preparation. This document presents a comprehensive financial outlook on expenditures, revenues, and borrowings for the medium term, outlining broad strategic priorities and policy goals for the upcoming financial year, 2024-2025. It aligns with the development strategies detailed in the 3rd Generation County Integrated Development Plan (CIDP) for 2023-2027. The CFSP 2025 establishes indicative sector ceilings based on identified priorities and programs, providing a policy framework for resource allocation across various county departments. It has been crafted against the backdrop of anticipated economic recovery following global disruptions, including high interest rates and conflicts that have affected credit access and increased debt servicing costs. Despite these challenges, the Kenyan economy has shown resilience, growing by an average of 5.6 percent in the first three quarters of 2023, which surpasses global and Sub-Saharan averages. This growth is expected to continue, driven by a robust private sector, improvements in agriculture, and national policies aimed at stimulating key sectors. The county's economic outlook is closely tied to national trends, with agriculture being a primary economic driver. The successful implementation of the budget is critical for sustainable growth, requiring collaboration among stakeholders such as government departments, civil society, and development partners to foster a prosperous community
Isiolo County Programme Based Budget 2025/2026
Get PDFThe FY 2025/26-2027/28 budget predictions were developed in accordance with PFM Act 2012 Section 125, which requires the county administration to construct and submit the county budget to the county assembly by April 30 each year. Furthermore, Section 12 of the second schedule of the PFM Act 2012 requires the county government to employ a program-based budgeting (PBB) technique. The budget for 2025/26 aims to accomplish two primary objectives: prioritizing budget expenditure by allocating resources to programs that provide significant public benefits and encouraging county government sectors to be efficient and effective in service delivery by shifting the focus of public spending from input to results. This will ensure that output and outcomes are geared toward achieving county-specific goals.
Budget Outlook: The FY 2025/26 budget estimates were prepared by sector working groups, following the Medium-Term Expenditure Framework guidelines outlined in the 2025 County Treasury Circular. These estimates comply with the Constitution 2010 and the Public Finance Act 2012, with the content guided by the County Fiscal Strategy Paper 2025 and the County Integrated Development Plan 2023-27. Article 201 of the Constitution (2010) encourages transparency and accountability in public financial matters. The budget estimates were based on citizen input from budget public consultation forums held in February and
April 2025. FY 2025/26 resource allocation focuses on implementing programs and strategies from County Fiscal Strategy Paper 2025 and the 2025/26 FY Annual Development Plan
Kirinyaga County Fiscal Strategy Paper 2025
Get PDFThe 2025 County Fiscal Strategy Paper (CFSP) sets out the broad priority strategies and policies that will guide the County Government of Kirinyaga in preparing the budget for the 2025/26 Financial Year and the Medium Term. This document is prepared in line with Section 117 of the Public Finance Management (PFM) Act, 2012, which mandates the County Treasury to submit the CFSP to the County Executive Committee for approval and subsequently to the County Assembly by 28th February each year. The 2025 CFSP has been developed against a backdrop of economic recovery and resilience-building, both at the national and county levels. The Kenya Kwanza Administration has reaffirmed its commitment to the Bottom-Up Economic Transformation Agenda (BETA), which emphasizes stabilizing government finances, driving inclusive economic growth, and addressing market failures. At the county level, Kirinyaga continues to prioritize economic transformation through strategic investments in agriculture, healthcare, infrastructure, trade, and industrialization. The 2025 CFSP outlines priority interventions that will accelerate economic growth, enhance service delivery, and improve the livelihoods of Kirinyaga residents. Key thematic areas that will drive this transformation include: Agricultural Transformation and Food Security – Continued support for value chain development, strengthening agro-processing and market linkages.
Industrialization and Trade Development – Enhancing economic diversification through investments in the Sagana Agro-Industrial City, County Aggregation Industrial Park (CAIP), and Export Processing Zone (EPZ). Universal Health Coverage (UHC) Expansion – Strengthening health infrastructure, upgrading Kianyaga and Kimbimbi hospitals, and expanding community-based health programs. Infrastructure and Urban Development – Investing in rural and urban roads, affordable housing projects, and water and sewerage systems
Policy Paper No. 08 of 2025 on Alcohol Tax Simulation Model for Kenya 2025: Methodological Note
Get PDFThe Kenya Alcohol Tax Simulation Model is an Excel-based tool designed to help policy makers and analysts assess how changes in alcohol tax policy affect prices, consumption and government revenue.
The Model is intended for researchers and policy makers seeking to evaluate the revenue and public health impacts of alcohol tax policy changes. It serves as a decision-support tool that enables users to forecast how different tax scenarios could contribute to government revenue targets while influencing alcohol consumption and related health outcomes. Like other economic analysis toolkits developed by the World Bank, WHO, and Tobacconomics, it is designed to strengthen local capacity and build a robust evidence base to inform effective alcohol taxation policies that balance fiscal and public health objectives