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  • Effective carbon taxes cut emissions but weaken macroeconomic activity

    What the study found

    The study finds that effective carbon taxes reduce emissions, but they also appear to impair macroeconomic activity. The results vary somewhat across sectors and countries.

    Why the authors say this matters

    The authors present a new monthly measure of effective carbon tax rates that accounts for changes in how emissions are covered by taxes. They suggest this measure helps address problems with carbon tax measures used in earlier research.

    What the researchers tested

    The paper examines sectoral and macroeconomic consequences of carbon taxes in four Nordic countries. It uses a novel monthly measure of effective carbon tax rates and applies it in a local projection setting, a method for estimating how effects change over time.

    What worked and what didn't

    Using the new measure, the study finds that carbon taxes work as expected in reducing emissions. However, the same taxes are also associated with weaker macroeconomic activity, and the size of the effects differs across sectors and countries.

    What to keep in mind

    The abstract does not describe detailed limitations beyond noting heterogeneity across sectors and countries. It also does not provide the size of the effects or information on individual tax designs beyond the new monthly measure.

    • The study examines carbon taxes in four Nordic countries.
    • It introduces a monthly measure of effective carbon tax rates.
    • The measure accounts for time-varying emission coverage from explicit and implicit taxes on greenhouse gas-emitting goods.
    • Carbon taxes are found to reduce emissions.
    • Carbon taxes are also found to impair macroeconomic activity, with some heterogeneity across sectors and countries.
  • ESG ratings show stronger financial links in hotel REITs

    ESG ratings show stronger financial links in hotel REITs

    What the study found

    The study found that hotel-focused real estate investment trusts, or REITs, appear to benefit more financially from higher ESG ratings than REITs in other real estate sectors. The reported gains were driven mainly by capital gains rather than operating income.

    Why the authors say this matters

    The authors conclude that the findings reinforce sector-specific financial implications of ESG adoption. They also suggest that ESG initiatives in hotel REITs function as firm-specific strategic capabilities, including energy efficiency, governance quality, and social responsibility.

    What the researchers tested

    The researchers examined whether ESG scores were related to financial performance in global REITs, with particular attention to the hotel sector. They analyzed 5,241 firm-year observations from 37 countries covering 2001 to 2022, using ESG ratings from MSCI and financial data from Bloomberg and Compustat via WRDS.

    What worked and what didn't

    The analysis reported a stronger positive ESG-performance association for hotel REITs than for REITs focused on other sectors. ESG investment was associated with improved financial returns in hotels, mainly through higher capital gains. The abstract does not report any sector where ESG had a stronger effect than in hotel REITs.

    What to keep in mind

    The summary provided does not describe specific limitations, so none can be stated here. The results are based on global REIT data from 2001 to 2022 and may apply only within that scope.

    • Hotel-focused REITs showed a stronger financial benefit from ESG improvements than other REIT sectors.
    • The reported financial benefit came mainly from capital gains, not operating income.
    • The study used 5,241 firm-year observations from REITs in 37 countries between 2001 and 2022.
    • ESG scores came from MSCI, and financial data came from Bloomberg and Compustat via WRDS.
    • The authors link the pattern to a positive ESG-performance association that is strongest in hotel REITs.

  • Low-precision LP solutions supported fix-and-propagate heuristics

    What the study found

    The study found that low-precision linear programming (LP) solutions can be used in a fix-and-propagate heuristic for mixed-integer programming (MIP) without lowering the quality of the heuristic's solutions. The authors also report that this approach produced high-accuracy solutions for very large planning problems.

    Why the authors say this matters

    The authors suggest this matters because it shows that low-accuracy LP solutions from first-order methods can still be useful inside a fix-and-propagate framework. They also indicate that the approach can help solve large-scale optimization problems more effectively than the commercial solvers they compared against.

    What the researchers tested

    The researchers tested a fix-and-propagate (FP) heuristic for mixed-integer programming problems, using GPU-accelerated PDLP, a first-order method for linear programming relaxations, to solve the LP relaxation to low accuracy. They evaluated the heuristic on MIPLIB2017 and on unit commitment-based dispatch and expansion planning problems built with the REMix modeling framework.

    What worked and what didn't

    On MIPLIB2017, low-accuracy LP solutions did not reduce the quality of the fix-and-propagate heuristic solutions. For the largest REMix problems, the framework produced solutions with a primal-dual gap of under 2% in less than 4 hours, while state-of-the-art commercial solvers could not produce feasible solutions within 2 days. The abstract does not describe any case where the approach failed on the tested problems.

    What to keep in mind

    The summary only reports results for the tested benchmark set and REMix-generated planning problems, so the abstract does not establish how the approach performs beyond those settings. It also does not provide detailed information about parameter choices, problem instances, or possible limitations of the heuristic beyond the reported comparisons.

    • Low-precision LP solutions were used to guide fix-and-propagate heuristics for mixed-integer programming.
    • On MIPLIB2017, low-accuracy LP inputs did not reduce heuristic solution quality.
    • The method produced solutions with under 2% primal-dual gap for the largest REMix problems in less than 4 hours.
    • State-of-the-art commercial solvers did not produce feasible solutions within 2 days on those largest problems.
    • The tested large problems reached up to 243 million nonzeros and 8 million decision variables.

  • Modified PYTHIA mPDFs better satisfy symmetry and sum rules

    What the study found

    The study found that an updated PYTHIA-based construction for equal-scale multi-parton distribution functions can give symmetric functions and improve agreement with the required number and momentum sum rules. For double and triple parton distribution functions, the sum rules were obeyed to within 10% over most of the tested phase space.

    Why the authors say this matters

    The authors say multi-parton distribution functions are important for predicting multiple scattering rates at hadron colliders. They suggest their improved construction matters because the earlier PYTHIA model could not satisfy both symmetry and the sum rules at the same time.

    What the researchers tested

    The researchers introduced an algorithm for equal-scale multi-parton distribution functions based on the PYTHIA procedure, with three additional modifications. They tested it on double parton distribution functions (dPDFs) and triple parton distribution functions (tPDFs), and also used the dPDFs to compute rapidity asymmetries for same-sign WW and ZZ production via double parton scattering.

    What worked and what didn't

    The modified construction produced symmetric dPDFs and tPDFs that met the sum rules to within about 10% for most of the phase space and scales tested, with deviations only mildly above that level. The study also compared the rapidity-asymmetry predictions with results from PYTHIA and the GS09 dPDFs, but the abstract does not state a clear winner among those comparisons.

    What to keep in mind

    The summary only reports results for the equal-scale case, where all partons share the same scale. The abstract does not describe detailed limitations beyond the noted deviations from the sum rules, and it does not provide the full comparison outcomes for the collider predictions.

    • The paper addresses equal-scale multi-parton distribution functions, which are used in predictions for multiple scattering at hadron colliders.
    • An updated PYTHIA-based algorithm was built with three extra modifications.
    • The new construction aims to produce symmetric mPDFs that better satisfy number and momentum sum rules.
    • For dPDFs and tPDFs, the sum rules were obeyed to within 10% over most of the tested phase space.
    • The dPDFs were used to compute rapidity asymmetries for same-sign WW and ZZ production via double parton scattering.

  • Price level, interest rates, and regulation were linked to FDI patterns

    What the study found

    The study found that price level, interest rate spread, and regulatory quality were related to foreign direct investment (FDI) in the BRICS and GCC country groups, but the patterns differed across groups and between the short run and the long run. The authors report positive and negative associations in different cases, depending on the estimator and region.

    Why the authors say this matters

    The authors conclude that the findings improve understanding of how large interest rate spreads and high price levels can shift foreign investment amounts, which they describe as important for balanced economic growth. They also say countries should address institutional conditions and regulatory frameworks before trying to stimulate FDI.

    What the researchers tested

    The researchers carried out a comparative panel-data analysis of four BRICS countries and four GCC countries over 2005 to 2023, using 76 observations in each group. They examined the effects of interest rate spread, regulatory quality, and price level on FDI, and used second-generation panel methods because of cross-sectional dependence, including the CIPS unit root test, Westerlund cointegration with bootstrap, and long-run estimators such as PMG and CCEMG.

    What worked and what didn't

    In BRICS, the PMG estimator showed a significantly positive short-run relationship between price level and FDI. In the GCC, the PMG estimator showed a significantly positive long-run relationship between interest rate spread and FDI, and significantly negative long-run relationships between price level and FDI and between regulatory quality and FDI. As a robustness check, CCEMG also showed a significantly positive long-run relationship between price level and FDI and a significantly negative long-run relationship between regulatory quality and FDI in BRICS, while the GCC CCEMG results were consistent with PMG for regulatory quality, interest rate spread, and price level.

    What to keep in mind

    The abstract does not provide the full country list beyond noting that India, the UAE, and Saudi Arabia were excluded because of unavailable data. It also does not describe the size or direction of effects in numerical detail, only whether relationships were statistically significant and positive or negative.

    • The study examined FDI in four BRICS countries and four GCC countries from 2005 to 2023.
    • Price level was significantly positively related to FDI in the BRICS short run in the PMG results.
    • In the GCC, interest rate spread was significantly positively related to FDI in the long run, while price level and regulatory quality were significantly negatively related to FDI in the PMG results.
    • Robustness checks with CCEMG showed a positive long-run price level–FDI link and a negative long-run regulatory quality–FDI link in BRICS.
    • The authors say countries should address institutional conditions and regulatory frameworks before trying to stimulate FDI.

  • CSR linked to sustainable competitive advantage in Ghanaian public sector

    What the study found

    The study found that corporate social responsibility was positively related to sustainable competitive advantage, green human resource management, and technological adaptability. It also found that green human resource management and technological adaptability were each positively related to sustainable competitive advantage.

    Why the authors say this matters

    The authors conclude that corporate social responsibility, green human resource management, and technological adaptability may be useful strategies for achieving sustainable competitive advantage. They describe this as actionable guidance for managers.

    What the researchers tested

    The researchers used Institutional Theory and the Resource-Based View to examine whether green human resource management and technological adaptability mediate the relationship between corporate social responsibility and sustainable competitive advantage. They analyzed data from 283 managers in the Ghanaian public sector using partial least squares structural equation modeling.

    What worked and what didn't

    Corporate social responsibility showed a significant positive relationship with sustainable competitive advantage, green human resource management, and technological adaptability. Green human resource management and technological adaptability also positively influenced sustainable competitive advantage and each partially mediated the relationship between corporate social responsibility and sustainable competitive advantage. The serial mediation roles of green human resource management and technological adaptability were confirmed.

    What to keep in mind

    The abstract does not describe detailed limitations. The findings are based on managers in the Ghanaian public sector, so the scope is limited to that sample.

    • Corporate social responsibility was positively related to sustainable competitive advantage.
    • Corporate social responsibility was also positively related to green human resource management and technological adaptability.
    • Green human resource management and technological adaptability each positively influenced sustainable competitive advantage.
    • Both factors partially mediated the link between corporate social responsibility and sustainable competitive advantage.
    • The serial mediation of green human resource management and technological adaptability was confirmed.
  • Molybdenum increased soybean nodulation and seed yield

    Molybdenum increased soybean nodulation and seed yield

    What the study found

    The study found that molybdenum, a micronutrient needed for nitrogenase activity in nitrogen fixation, improved soybean nodulation and seed yield under field conditions. The highest molybdenum rate tested, 52.5 ppm, gave the strongest overall yield response.

    Why the authors say this matters

    The authors conclude that molybdenum is important in nutrient management strategies for legume crops. The findings indicate that supporting nodulation, the formation of root nodules that help fix nitrogen from the air, is linked to greater soybean productivity.

    What the researchers tested

    The researchers conducted a field study in Telapayong, Arayat, Pampanga, Philippines. They compared a control, the recommended rate of fertilizer (28-28-58 kg ha−1 of N-P-K), and molybdenum applied at 31.5, 42.0, and 52.5 ppm.

    What worked and what didn't

    Molybdenum at 52.5 ppm significantly increased plant height at 30 and 60 days after sowing compared with the control and the recommended fertilizer rate. Flowering was earlier with 42.0 ppm, and nodulation traits at the R2 and R3 stages improved significantly with 42.0 and 52.5 ppm. The highest molybdenum level also increased pod number and seed yield, while the abstract does not report benefits for the control treatment beyond being the comparison group.

    What to keep in mind

    The abstract describes one field location and one soybean study, so the findings are limited to the tested conditions. It also does not describe any drawbacks, adverse effects, or longer-term outcomes.

    • Molybdenum fertilization improved soybean nodulation and seed yield in field conditions.
    • The highest tested rate, 52.5 ppm, produced the largest increases in plant height, pod number, and seed yield.
    • Flowering occurred earlier with 42.0 ppm molybdenum.
    • Nodule count, nodule formation rate, and nodule biomass improved at the R2 and R3 growth stages.
    • Nodulation traits were positively correlated with yield components.

  • Particle creation model reproduces cosmic expansion without dark energy

    What the study found

    The study proposes a cosmological model with no dark energy, based on gravitationally induced adiabatic particle creation. The authors report that this model can reproduce a Lambda-CDM-like expansion for suitable values of alpha, while beta allows small deviations from the standard cosmic concordance model.

    Why the authors say this matters

    The authors conclude that the model offers a singularity-free, unified scenario that evolves smoothly between two extreme de Sitter phases, and they suggest it provides a new perspective for addressing the Hubble constant and S8 tensions. They also state that it may help solve older cosmological puzzles.

    What the researchers tested

    The researchers examined a dark-energy-free cosmological model with four components and two free parameters, alpha and beta. They compared its predictions with type Ia supernova data from Pantheon+SH0ES and H(z) data, where H(z) refers to measurements of the expansion rate as a function of redshift.

    What worked and what didn't

    For suitable alpha values, the model reproduces a Lambda-CDM-like expansion. The data constrain beta to be about 0.13, which the authors describe as indicating a mild departure from standard cosmology; they also note that this may offer some relief of the H0 and S8 tensions.

    What to keep in mind

    The abstract does not describe detailed limitations beyond the parameter constraints reported from the data. The claims about tension relief and a unified scenario are presented by the authors as conclusions from the model, not as established empirical resolution.

    • The paper proposes a dark-energy-free cosmological model based on gravitationally induced adiabatic particle creation.
    • The model is described as having four components and two free parameters, alpha and beta.
    • The authors report that suitable alpha values produce Lambda-CDM-like expansion.
    • Data from Pantheon+SH0ES supernovae and H(z) measurements suggest beta is about 0.13.
    • The authors say the model may offer a mild departure from standard cosmology and possible relief of the H0 and S8 tensions.

  • CAD alone outperformed CAD-plus-CRP tuberculosis screening

    What the study found

    Computer-aided detection (CAD) software used on digital chest X-rays alone found more tuberculosis cases and cost less than CAD followed by C-reactive protein (CRP, a blood test that can indicate inflammation) testing. The combined approach did not meet the study's non-inferiority criterion.

    Why the authors say this matters

    The authors conclude that, in community active tuberculosis case-finding, CAD followed by CRP offered no advantage over CAD alone because it had lower case yield and higher cost. They also suggest that CAD alone could be an effective and economically viable screening strategy in high-burden areas.

    What the researchers tested

    This pragmatic community trial with a paired screen-positive design compared two screening approaches within the same participants. Adults in households in Butha-Buthe District, Lesotho, and uMgungundlovu District, South Africa, were screened using CAD4TBv7 alone or CAD4TBv7 followed by CRP testing when the CAD score fell in a specified range, with confirmatory Xpert MTB/RIF Ultra testing when required.

    What worked and what didn't

    Among 20,023 enrolled participants, the primary outcome set included 73 people with tuberculosis identified by at least one approach and complete data for both. CAD4TBv7 identified 69 of these cases (94.5%), while CAD4TBv7-CRP identified 60 (82.2%); the difference was -12.3%, so the non-inferiority criterion was not met. The cost per detected tuberculosis case was US$5,454 for CAD4TBv7 and US$7,486 for CAD4TBv7-CRP, making the combined approach 37.3% more expensive.

    What to keep in mind

    The comparison was limited to the study's community setting in two districts and to the participants who met eligibility criteria. The abstract does not describe additional limitations beyond the non-inferiority failure and the cost difference.

    • CAD alone detected 69 of 73 tuberculosis cases in the primary outcome set.
    • CAD followed by CRP detected 60 of 73 cases and did not meet non-inferiority.
    • The combined CAD-CRP approach cost more per detected case than CAD alone.
    • The study enrolled 20,023 adults from community settings in Lesotho and South Africa.
    • The authors conclude that CAD alone may be a viable screening strategy in high-burden settings.

  • Adjacent iron sites enable methane conversion to ethanol

    What the study found

    The study found that a catalyst with adjacent iron sites can steer methane conversion toward ethanol. The catalyst achieved ethanol production from methane at 25 °C and 0.5 MPa, with high selectivity reported in the abstract.

    Why the authors say this matters

    The authors say this matters because selective oxidation of methane to C2 oxygenates, meaning two-carbon oxygen-containing products, under mild conditions is important for methane valorization. They also note that the process is difficult because methane is inert, overoxidation competes, and carbon-carbon coupling is slow.

    What the researchers tested

    The researchers tested an N,S co-doped carbon nanotube-supported Fe5 cluster catalyst, called Fe5/NSC. They combined experimental investigation with density functional theory calculations to examine how adjacent iron sites affect methane activation and coupling steps.

    What worked and what didn't

    The catalyst produced ethanol with a productivity of 1939.6 μmol·gcat–1·h–1 and a selectivity of 83.9% under the stated conditions, without added CO. The abstract says adjacent iron sites favor sequential C–H activation and C–C coupling through distinct C1 intermediates, *OCH2 and *CH3, leading to CH3CH2O* and then ethanol. In contrast, the conventional CHx–CO coupling pathway is described as primarily yielding acetic acid.

    What to keep in mind

    The summary provided does not describe detailed experimental limitations or broader scope beyond the reported conditions. The findings are specific to the Fe5/NSC catalyst and the methane-to-ethanol conversion route described in the abstract.

    • A nitrogen- and sulfur-doped carbon nanotube-supported Fe5 cluster catalyst converted methane to ethanol.
    • The abstract reports ethanol productivity of 1939.6 μmol·gcat–1·h–1 and selectivity of 83.9% at 25 °C and 0.5 MPa CH4.
    • The authors say adjacent iron sites enable sequential C–H activation and C–C coupling.
    • Experimental work and density functional theory calculations were used to study the mechanism.
    • The abstract contrasts the ethanol-forming route with conventional CHx–CO coupling, which primarily yields acetic acid.