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Policy Monitor Issue 18 No. 01 July-September 2025 on Harnessing Value Chains for Sustainable and Inclusive Growth
Full text linkThe articles in this edition focus on Kenya’s recent economic developments; strengthening the indigenous chicken value chain for sustainable livelihoods; strengthening the competitiveness of Kenya’s MSMEs’ leather and leather products value chains; and decoding the AI value chain for economic growth in Kenya.
This Edition highlights various activities undertaken by the Institute in the first quarter. Among the key activities are the side event on Advancing Social Equity, Inclusion, and Justice through Public Participation at the Devolution Conference, and the launch of the Kenya Country Economic Transformation Outlook Report.
Additionally, the Institute organized dissemination workshops, including one on Leveraging SDR for Sustaining Economic Recovery in Kenya and a validation workshop on the Follow-up National Survey on Unclaimed Financial Assets. Further, the Policy Monitor highlights several roundtables and stakeholder workshops held during this period on various thematic and interdisciplinary research areas, including a roundtable on the RESET Project and a National Policy Dialogue on Circularity and Used Textiles Trade in Kenya
Optimizing the diffusion coefficient of overdamped Langevin dynamics
No full textInternational audienceOverdamped Langevin dynamics are reversible stochastic differential equations which are commonly used to sample probability measures in high-dimensional spaces, such as the ones appearing in computational statistical physics and Bayesian inference. By varying the diffusion coefficient, there are in fact infinitely many overdamped Langevin dynamics which are reversible with respect to the target probability measure at hand. This suggests to optimize the diffusion coefficient in order to increase the convergence rate of the dynamics, as measured by the spectral gap of the generator associated with the stochastic differential equation. We analytically study this problem here, obtaining in particular necessary conditions on the optimal diffusion coefficient. We also derive an explicit expression of the optimal diffusion in some appropriate homogenized limit. Numerical results, both relying on discretizations of the spectral gap problem and Monte Carlo simulations of the stochastic dynamics, demonstrate the increased quality of the sampling arising from an appropriate choice of the diffusion coefficient
Observation of the open-charm tetraquark state in the decay
No full textInternational audienceAn amplitude analysis of decays is performed using proton-proton collision data, corresponding to an integrated luminosity of , collected with the LHCb detector at center-of-mass energies of 7, 8, and 13. A resonant structure of spin-parity is observed in the invariant-mass spectrum with a significance of . The mass and width of the state, modeled with a BreitWigner lineshape, are determined to be and respectively, where the first uncertainties are statistical and the second systematic. These properties and the quark content are consistent with those of the open-charm tetraquark state observed previously in the final state of the decay. This result confirms the existence of the state in a new decay mode. The state, reported in the decay, is also searched for in the invariant-mass spectrum of the decay, without finding evidence for it
Study of Λ0 b and Ξ0 b decays to Λh+h ′− and evidence for CP violation in Λ0 b → ΛK+K− decays
No full textInternational audienceA study of Λ 0 b and Ξ0 b decays to Λh+h ′− (h (′) = π, K) is performed using pp collision data collected by the LHCb experiment during LHC Runs 1–2, corresponding to an integrated luminosity of 9 fb−1 . The branching fractions for these decays are measured using the Λ 0 b → Λ + c (→ Λπ+)π − decay as control channel. The decays Λ 0 b → Λπ+π − and Ξ0 b → ΛK−π + are observed for the first time. For decay modes with sufficient signal yields, CP asymmetries are measured in the full and localized regions of the final-state phase space. Evidence is found for CP violation in the Λ 0 b → ΛK+K− decay, interpreted as originating primarily from an asymmetric Λ 0 b → N∗+K− decay amplitude. The measured CP asymmetries for the other decays are compatible with zero
Multi-wavelength study of OT 081: broadband modelling of a transitional blazar
No full textInternational audienceOT 081 is a well-known, luminous blazar that is remarkably variable in many energy bands. We present the first broadband study of the source which includes very-high-energy (VHE, 100 GeV) -ray data taken by the MAGIC and H.E.S.S. imaging Cherenkov telescopes. The discovery of VHE -ray emission happened during a high state of -ray activity in July 2016, observed by many instruments from radio to VHE -rays. We identify four states of activity of the source, one of which includes VHE -ray emission. Variability in the VHE domain is found on daily timescales. The intrinsic VHE spectrum can be described by a power-law with index (MAGIC) and (H.E.S.S.) in the energy range of 55--300 GeV and 120--500 GeV, respectively. The broadband emission cannot be sucessfully reproduced by a simple one-zone synchrotron self-Compton model. Instead, an additional external Compton component is required. We test a lepto-hadronic model that reproduces the dataset well and a proton-synchrotron dominated model that requires an extreme proton luminosity. Emission models that are able to successfully represent the data place the emitting region well outside of the Broad Line Region (BLR) to a location at which the radiative environment is dominated by the infrared thermal radiation field of the dusty torus. In the scenario described by this flaring activity, the source appears to be an FSRQ, in contrast with past categorizations. This suggests that the source can be considered to be a transitional blazar, intermediate between BL~Lac and FSRQ objects
Elliptic anisotropy measurement of the f(980) hadron in proton-lead collisions and evidence for its quark-antiquark composition
No full textInternational audienceDespite the f(980) hadron having been discovered half a century ago, the question about its quark content has not been settled: it might be an ordinary quark-antiquark () meson, a tetraquark () exotic state, a kaon-antikaon () molecule, or a quark-antiquark-gluon () hybrid. This paper reports strong evidence that the f(980) state is an ordinary meson, inferred from the scaling of elliptic anisotropies () with the number of constituent quarks (), as empirically established using conventional hadrons in relativistic heavy ion collisions. The f(980) state is reconstructed via its dominant decay channel f(980) , in proton-lead collisions recorded by the CMS experiment at the LHC, and its is measured as a function of transverse momentum (). It is found that the = 2 ( state) hypothesis is favored over = 4 ( or states) by 7.7, 6.3, or 3.1 standard deviations in the 10, 8, or 6 GeV/ ranges, respectively, and over = 3 ( hybrid state) by 3.5 standard deviations in the 8 GeV/ range. This result represents the first determination of the quark content of the f(980) state, made possible by using a novel approach, and paves the way for similar studies of other exotic hadron candidates
Signed tropicalization of polar cones
No full textInternational audienceWe study the tropical analogue of the notion of polar of a cone, working over the semiring of tropical numbers with signs. We characterize the cones which arise as polars of sets of tropically nonnegative vectors by an invariance property with respect to a tropical analogue of Fourier-Motzkin elimination. We also relate tropical polars with images by the nonarchimedean valuation of classical polars over real closed nonarchimedean fields and show, in particular, that for semi-algebraic sets over such fields, the operation of taking the polar commutes with the operation of signed valuation (keeping track both of the nonarchimedean valuation and sign). We apply these results to characterize images by the signed valuation of classical cones of matrices, including the cones of positive semidefinite matrices, completely positive matrices, completely positive semidefinite matrices, and their polars, including the cone of co-positive matrices, showing that hierarchies of classical cones collapse under tropicalization. We finally discuss an application of these ideas to optimization with signed tropical numbers
Mandera County Annual Development Plan 2025/2026
No full textThis is the third Annual Development Plan that implements the third County Integrated Development Plan 2023-2027(CIDP) pursuant to section 126 of the Public Finance Management Act (2012). It outlines the broad development programmes and objectives, with clear outputs and indicators to be achieved by the county in this plan.
The ADP contains priority development programmes/projects that have been identified for implementation during the 2025/2026 financial year. In this regard, the plan has identified strategic development objectives in all sectors and proposed programmes which are designed to meet the respective objectives. These programmes are geared towards addressing development challenges that the County must progressively respond to in order to achieve its vision of “Regionally competitive and self-reliant county”.
It is important to note that as a county government we have developed a county integrated development plan which is our blue print and hence no public funds shall be appropriated outside a planning framework developed by the county executive committee and approved by the county assembly. The County Integrated Development plan (CIDP) provides the foundation for the preparation of the County Annual Development Plan (CADP) which provides comprehensive baseline information on infrastructural and socio-economic characteristics of the county and will be the basis of spending and budgeting in the county for financial year 2025/2026. It is expected that successful implementation of the
programmes/projects envisaged in this Annual Development Plan will result into better delivery of services contributing immensely to the growth of the local economy
Murang'a County Programme Based Budget 2025/2026
No full textThe budget estimates for the 2025-2026 financial year were prepared in line with the Public Finance Management Act, 2012 and County Fiscal Strategy Paper 2025. The estimates were also guided by the strategic interventions identified in the County Integrated Development Plan 2023-2027 and the Bottom-up Transformative Agenda (BETA)
Key areas of intervention remain food security and value addition, provision of sufficient reliable water, effective and accessible road network across the county, provision of universal health care for all and social and economic empowerment of youth, women and people living with disabilities. The specific programmes identified and prioritized through a rigorous process of public participation include...............................
Nandi County Annual development Plan 2026/2027
No full textThe Public Finance Management Act (PFMA), 2012 section 126 outlines the county planning framework which provides for the preparation of various plans among them the Annual Development Plans (ADPs). The ADP provides the basis for implementing the County Integrated Development Plan (CIDP) and guiding resource allocation to priority programmes and projects. The ADP process disaggregates the CIDP priorities into short-term one-year targets. The ADP also provides means for linking the County development priorities to the Kenya Vision 2030 and its MTP IV and the Bottom-Up Economic Transformation Agenda (BETA).
The ADP for FY 2026/2027 was developed through a collaborative and inclusive process involving all stakeholders including the public, organized groups, professionals, development partners and investors. Public participation forums were held across all the County thirty wards, ensuring that the contributions of all stakeholders were reflected in the plan. This consultative approach allowed for the identification of key programs and priorities that directly address the county's most pressing challenges and opportunities while ensuring that ongoing programs and projects are prioritized to achieve the set goals. Preparation process of the 2026/2027 Annual Development Plan complied with the Nandi County Equitable Development Act, 2023. The outcome of this consultative process include the prioritization of ward level projects amounting to Ksh. 1.205 billion for all the County thirty Wards according to the allocation formula contained in the Nandi County Equitable Development Act, 2023. In addition, County level priority programs and
projects that have high impact on socio economic transformation of the county amounting Ksh 2.771 billing were also identified. County transformative projects amounting g Ksh 1.416 billion will be funded
through the remaining 50% of total development allocation from equitable share and County Own Source Revenue while funding for the prioritized projects amounting to Ksh. 1.355 Million will be funded through the National Government and Development Partners. This policy document focuses on prioritizing high-impact transformative programs, sectoral interventions and grass-root priority projects designed to enhance the well-being of Nandi County citizens. It highlights the County Government's dedication to improving healthcare by upgrading health infrastructure and increasing access to quality services. The plan also emphasizes, expanding and maintaining road networks; quality ECDE & VTC education; ensuring access to clean and safe water to all residents through connectivity and boosting agricultural productivity. Additionally, the plan stresses the importance of promoting agribusiness & value chain; promoting gender equity & inclusivity and creating a favourable environment for trade and sustainable economic growth. Moreover, the ADP aims at the integration of National, Regional, and International Development Frameworks. It intends to capitalize on strengths and opportunities while addressing challenges that slow the county's progress