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Retaliation, retribution, and punishment and international law
No full textOn April 13, Iran launched a massive missile and drone attack on Israel. Hezbollah and Houthi attacks took place contemporaneously. Israel, alongside forces from France, the United Kingdom, the United States, and Jordan, successfully neutralized most of these threats, with several Arab States providing indirect support. Widespread denunciation of Iran’s actions followed. For instance, the G7 “condemn[ed] in the strongest terms Iran’s direct and unprecedented attack,” expressed “full solidarity and support to Israel and its people,” and reaffirmed its commitment toward Israel’s security.
Iran’s attack was a response to Israel’s April 1 airstrike on individuals located inside Iran’s Consulate in Damascus. The operation killed two senior Iranian Revolutionary Guard Generals, along with five other officers, a member of Hezbollah, and two Syrians. The day after the attack, Iran’s supreme leader, Ayatollah Ali Khamenei, threatened, “We will make them regret this crime and other similar ones with the help of God.” Iran’s attack was an attempt to make good on that threat.
The question is, “What next?” Iranian officials claim its “operation yielded its complete result” and “there is no intention to continue it,” although it is far from certain that Iran is ready to put an end to its long-running “shadow war” with Israel. Meanwhile, Israel seems intent on responding. For instance, Lieutenant General Herzi Halevi, the Israel Defense Forces’ Chief of Staff, stated that “the launch of so many missiles and drones to Israeli territory will be answered with a retaliation.” In response to such statements, Iranian President Ebrahim Raisi has warned, “The slightest action against Iran’s interests will definitely be met with a severe, extensive and painful response.” The risk of escalation between Iran and Israel is palpable, as is the danger of the conflict sparking a regional conflagration
Impact of Atlantic multidecadal variability on rainfall intensity distribution and timing of the West African monsoon
Get PDFPrevious studies agree on an impact of the Atlantic multidecadal variability (AMV) on the total
seasonal rainfall amounts over the Sahel. However, whether and how the AMV affects the distribution of rainfall
or the timing of the West African monsoon is not well known. Here we seek to explore these impacts by analyzing
daily rainfall outputs from climate model simulations with an idealized AMV forcing imposed in the North
Atlantic, which is representative of the observed one. The setup follows a protocol largely consistent with the
one proposed by the Component C of the Decadal Climate Prediction Project (DCPP-C). We start by evaluating
model’s performance in simulating precipitation, showing that models underestimate it over the Sahel, where
the mean intensity is consistently smaller than observations. Conversely, models overestimate precipitation over
the Guinea coast, where too many rainy days are simulated. In addition, most models underestimate the average
length of the rainy season over the Sahel; some are due to a monsoon onset that is too late and others due to a
cessation that is too early. In response to a persistent positive AMV pattern, models show an enhancement in total
summer rainfall over continental West Africa, including the Sahel. Under a positive AMV phase, the number of
wet days and the intensity of daily rainfall events are also enhanced over the Sahel. The former explains most
of the changes in seasonal rainfall in the northern fringe, while the latter is more relevant in the southern region,
where higher rainfall anomalies occur. This dominance is connected to the changes in the number of days per
type of event; the frequency of both moderate and heavy events increases over the Sahel’s northern fringe.
Conversely, over the southern limit, it is mostly the frequency of heavy events which is enhanced, thus affecting
the mean rainfall intensity there. Extreme rainfall events are also enhanced over the whole Sahel in response to a
positive phase of the AMV. Over the Sahel, models with stronger negative biases in rainfall amounts compared
to observations show weaker changes in response to AMV, suggesting that systematic biases could affect the
simulated responses. The monsoon onset over the Sahel shows no clear response to AMV, while the demise
tends to be delayed, and the overall length of the monsoon season enhanced between 2 and 5 d with the positive
AMV pattern. The effect of AMV on the seasonality of the monsoon is more consistent to the west of 10°W,
with all models showing a statistically significant earlier onset, later demise, and enhanced monsoon season with the positive phase of the AMV. Our results suggest a potential for the decadal prediction of changes in the
intraseasonal characteristics of rainfall over the Sahel, including the occurrence of extreme events
Effect of tether length on endo/exo stereoselectivity in alkene–arene meta‐photocycloaddition reactions towards the Aphidocolin/Stemodin scaffolds
Get PDFIntramolecular alkene-arene meta-photocycloadditions are powerful transformations that use the enhanced reactivity of photoexcited benzene rings to facilitate addition of an alkene 1,3 across donor groups and form complex three-dimensional fused-ring systemsfrom readily accessible starting materials. Intramolecular examples havetraditionallybeen restricted to 3-memberedtethers, with cycloaddition resulting from exo-conformation. However, by judicious tether design we have demonstratedthat a 4-membered tether can also proceed in good yield; interestingly,viaan endo-exciplex(1.2:1) enabling access to both natural product skeletons and interesting scaffolds for medicinal chemistry research
Essays on M&As: the effect of political ideology divergence, climate change and technology on M&As
Get PDFThis thesis attempts to contribute to the strand of determinants of mergers and
acquisitions (M&As) and the performance of acquisitions in the US and international
markets, and it is composed of three main chapters.
The first main chapter examines the role of political ideology divergence (PID)
between the CEO and board of directors in the context of mergers and acquisitions.
Using a sample of 2,083 US-listed firms from 2000 to 2020, this study finds that firms
with greater PID are positively associated with the likelihood of engaging in M&A
activities. The results demonstrate that CEO risk-taking behaviours, proxied by CEO
overconfidence, founder CEO, and pay for performance sensitivity, explain this
positive relationship. Various identification strategies are employed to address
endogeneity concerns and confirm the robustness of the findings. Furthermore, the
research suggests that a higher level of PID has a positive effect on post-deal long-term
stock return and operating performance. This study also finds that monitoring, through
mechanisms such as board meeting frequency, institutional ownership, and independent
directors, plays a moderating role in this long-term performance. Overall, these findings
suggest that PID is a critical determinant of M&A decisions.
The second main chapter investigates the effect of firm-level climate change
exposures on mergers and acquisitions with global evidence. Using the climate change
exposures of Sautner et al. (2023), we find that firms facing higher climate change
exposure exhibit a reduced propensity to initiate and finalise acquisitions while
allocating more resources to capital expenditures. The increased cost of external
financing and low consumer confidence help explain the negative relationship between
climate change exposure and acquisition likelihood. This negative effect of climate
change exposure is more pronounced for acquirers of relatively small size, with steep
growth potential, facing financial constraints, and those operating within pro-cyclical
industries. When undertaking M&As, firms facing higher climate change exposure take
a longer time to complete a deal and post poor announcement returns and operating
performance. Several identification strategies address endogeneity concerns and ensure
the robustness of the findings. Overall, this study emphasises the importance of
considering climate change risks in M&A decision making.
The third main chapter investigates the post-merger short- and long-run
performance of technology-related M&As using a global sample. Deals are classified
according to the technological distance between acquirers and targets. Technologically
distant pairs lead to higher announcement returns for acquirer shareholders, especially
when targets are private. In contrast, pure technology deals gain significantly less and
even adversely affect firm value. The positive wealth effect of technologically distant
deals is more pronounced when the bidder is in a non-tech industry. Non-tech bidders
acquiring tech targets have the highest positive change in operating performance among
all acquisition types, suggesting better integration. Taken together, this study assesses
the short- and long-term performance of technology-related M&As, emphasising that
technologically distant firms yield higher returns for acquirers while similar technology
deals are less beneficial and may even reduce value.
This thesis critically analyses the factors influencing the initiation and
effectiveness of M&As in the US or international markets, encapsulated in three
chapters. It identifies political ideology divergence (PID) between the CEO and board,
the impact of climate change exposure, and the technological distance between
acquirers and targets as key determinants impacting M&A propensity, completion time,
stock returns, and post-deal performance
Approximating sparse Hessian matrices using large-scale linear least squares
Get PDFLarge-scale optimization algorithms frequently require
sparse Hessian matrices that are not readily available. Existing methods for approximating large sparse Hessian matrices have limitations. To try and overcome these, we propose a novel approach that reformulates the problem as the solution of a large linear least squares problem. The least squares problem is sparse but can include a number of rows that contain significantly more entries than other rows and are regarded as dense. We exploit recent work on solving such problems using either the normal equations or an augmented system to derive a robust approach for computing approximate sparse Hessian matrices. Example sparse Hessians from the CUTEst test problem collection for optimization illustrate the effectiveness and robustness of the new method
Britain – women in politics, 1918-29
No full textIn this course, Dr Jacqui Turner (University of Reading) explores women in politics after the First World War. In the first lecture, we think about whether women could be considered to have citizenship in 1918. In the second lecture, we think about the impact of the First World War on women’s citizenship. In the third lecture, we think about the political landscape for women after 1918. Next, we think about the establishment of new feminism. In the fifth lecture, we think about some key feminist figures in the interwar people. In the sixth and final lecture, we think about the societal impact of the Representation of the People (Equal Franchise) Act of 1928
Distance decay effects predominantly shape spider but not carabid community composition in crop fields in north-western Europe
Get PDFAgricultural intensification and expansion are regarded as main drivers of biodiversity loss. This conclusion is mainly based on observed declines of local diversity (α-diversity), while effects on community composition homogenization (decrease of β-diversity) at a larger spatial scale are less well understood. Carabid beetles and spiders represent two widespread guilds and are important predators of pest species. Here we surveyed carabid beetles and spiders in 66 winter wheat fields in four northwestern European countries (Germany, the Netherlands, Sweden and UK) and analyzed how their community composition was related to geographic distance (separation distance between any pairwise fields) and three environmental variables: crop yield (proxy for land-use intensity), percentage cropland (proxy for landscape complexity) and soil organic carbon content (proxy for local soil conditions). We further analyzed whether the relationship between carabid beetle and spider community composition and geographic distance was influenced by environmental variables. We found that, 55 % and 75 % of all observed carabid and spider individuals, respectively, belonged to species that occurred in all four countries. However, individuals of species that were unique to a particular country only accounted for 3 % of all collected individuals for both taxa. Furthermore, we found a negative relationship between distance and similarity of spider communities but not for carabid beetle communities. None of the environmental variables were related to similarity of carabid beetle and spider communities, nor moderated the effects of distance. Our study indicates that across a great part of the European continent, arthropod communities (especially carabid beetles) in agricultural landscapes are composed of very similar species that are robust to current variations in environment and land-use
Professional recognition in mathematics and data science: degree course accreditation chartership, fellowship
No full textOrnamental plants: our future invaders? Engaging with gardeners to tackle the issue of invasive species
No full textThe global nature crisis means that action to tackle the issue of invasive species is essential; not least because their number and impacts are expected to increase due to climate change. As well as being one of the direct drivers of the nature crisis, invasive species are estimated to have a global cost of £330Bn (IPBES, 2019) while also impacting on human health and way of life. Identifying potentially invasive species - or ‘future invaders’ - early is preferable. This project explores some of the parameters for identifying future invaders growing in gardens in Britain and Ireland, by engaging with gardeners, and suggesting solutions for reducing the risks associated with invasive ornamental plants.
The estimated 30 million gardens in the UK, with a rich diversity of ornamentals, represent a pool of future invaders. Gardeners in Britain and Ireland are therefore crucial actors. To engage with these gardeners, an exhibit at the Royal Horticultural Society’s Chelsea Flower Show - an annual focal point for amateur and professional gardeners alike - was developed to raise awareness of the issue and collect data by means of a survey.
Thematic analysis interpreted the meaning of ‘invasive’ from a gardener’s perspective. Increased public engagement was demonstrated to improve gardeners’ understanding of the term and the potential risks associated with invasive ornamentals. This project also showed that engaging with gardeners in their roles as ‘first contact’ for reporting future invaders, can be an effective means for prioritising ornamentals. From the many different plants grown, 558 gardeners reported 251 taxa of concern of which nine are prioritised using a structured approach for further research. There is considerable interest amongst gardeners in their critical role in managing invasive species and identifying future invaders. This interest needs to be encouraged and offers invasion science an important opportunity
Social-emotional competence among school-aged children in the Chinese context: validation of the Washoe County School District-Social emotional competency assessment
Get PDFThe present study aims to validate the 40-item and the brief 17-item Washoe County School District Social–Emotional Competency Assessment (WCSD-SECA), a self-report measure of social–emotional competencies, among Chinese school-aged children residing in Hong Kong. A total of 349 children (M = 9.86 years, SD = 1.22; 45.82% girls) and their parents (77.84% mothers) completed a set of questionnaires independently. The factor structure of both versions of the WCSD-SECA was assessed via confirmatory factor analyses. Structural equation models were then conducted to examine the predictive validity of the WCSD-SECA. The findings indicated that both the 40-item and the 17-item versions of the WCSD-SECA fit the data adequately. Both versions were also associated with self-reported positive and negative affect and parent-reported internalizing problems and externalizing problems. Additionally, social–emotional competencies as measured by the 40-item version were significantly associated with parent-reported prosocial behavior, whereas those as measured by the 17-item version were associated with prosocial behavior with a marginal significance. The findings demonstrated an adequate factor structure and predictive validity of the full version and the brief version of the WCSD-SECA in assessing social–emotional competencies. Hence, they serve as a useful tool for researchers, educators, and mental health practitioners to evaluate school-aged children’s social–emotional competencies in the Chinese context