Drought, Famine and Conflict: The Case of Two Pastoral Ethnic Communities in Turkana, Kenya

In this paper, I examine the link between famine and pastoral conflicts between two ethnic communities in Turkana, Kenya

Corporate Elections and Shareholder Proposal Rights: from Case Studies in South Korea

The idea of whether or not the shareholders of public firms should obtain access to the firms’ proxy materials has been controversial in the United States. The continual disagreements surrounding proxy access reforms demand the necessity of looking at other countries that already allow shareholder access to a company’s proxy. This article aims to explore the concerns and issues of shareholder proposal rights for corporate elections and shareholder access in South Korea and to provide considerations for an improved regime. Towards this end, this author conducted a case study of the shareholder proposals of public firms listed on the Korea Exchange over the periods 2007 through 2009. The analysis of the data suggests that shareholder proposals for director nominations have seldom been exercised for large public firms, especially chaebols—the large, family-controlled Korean corporate groups. Consequently, the current standards for a gradated shareholder eligibility requirement should be reconsidered, thus enabling shareholder nomination rights to function as an effective means to control agency problems in large public firms. Having cumulative voting systems and voting restrictions in auditor elections entail greater risks that directors or auditors representing special interests may be elected through shareholder nominations. In particular, considering the relatively large number of unsupported auditor nominations, a stricter requirement for auditor candidate nominations might mitigate the disadvantages of frivolous auditor nominations. In terms of nominating purposes, more than half of shareholder proposals were found to be utilized for the purpose of pursuing takeovers of control rights in South Korea, where there is no limitation on the number or qualification of directors to be nominated by shareholder proposal rights. This invites a reexamination of the proper scopes of shareholder nomination rights in conjunction with shareholder proxy access, depending upon the size of nomination. On the other hand, the fact that nominating shareholders frequently conduct a separate proxy solicitation shows that the current regime does not provide a sufficiently effective method for nominating shareholders. Future studies should include the effects of the exercise of shareholder nominations on enhancing corporate governance of the firms

The role and regulation of oxytocin/oxytocin receptor system in human amnion and labour

Preterm delivery occurs in 10% of all births. It is the major cause of infant death and handicap in the developed countries and accounts for 65% of neonatal deaths and 50% of childhood neurological disabilities. At the end of pregnancy, „pro-labour‟ factors begin to mediate remodeling of the cervix resulting in cervical ripening and dilatation, uterine contractility and decidual/fetal membrane activation. The amnion plays an important role in the onset of human labour. It is a major site for prostaglandins (PG) and inflammatory cytokine synthesis which increases both before and during labour. Amnion derived inflammatory cytokines and prostaglandins contribute to the relaxation of the lower uterine segment and to cervical ripening. Oxytocin (OT) and oxytocin receptor (OTR) are classically considered to play a fundamental role in the mechanism of labour as OT stimulates uterine contractions and OTR antagonists are clinically used as tocolytics. The increase in OT and OTR expressions were observed in tissues other than myometrium, including the breast cells, decidua and amnion. However, amnion is not a contractile tissue and therefore the physiological role of the OT/OTR is less obvious. We hypothesised that the regulation of OT/OTR in human amnion is linked to NF-κB activity and plays an important role in the onset of labour. We have demonstrated that in human amnion, labour induces expression of both OT and OTR expression. Using specific inhibitors and siRNA target knockdown studies, we have shown that unlike the myometrial OTR, OT binding to OTR in human amnion drives the receptor to couple with Gαi2 and Gαi3, but not Gαq. This subsequently triggers the sequential activation of ERK, p38 MAPKs and NF-κB signalling cascades leading to PG and proinflammatory cytokine/chemokine synthesis. This suggests that OT not only induces uterine contractions but also plays a role in triggering the onset of labour by mediating the proinflammatory effects in the amnion. These proinflammatory effects of OT were suppressed by an OTR-specific antagonist, ornithine vasotocin (OVT), indicating that OT exerts its effects predominantly via OTR. However, the commonly used OTR antagonist, atosiban, had no effect on OT induced proinflammatory effects. Unexpectedly, atosiban treatment alone resulted in activation of inflammatory mediators such as MAPKs and NF-κB leading to downstream pro-labour gene expressions via Gαi. Activation of such inflammatory processes within the uterus initiates labor, whereas exposure to inflammation may be associated with fetal brain damage in preterm and term infants. Therefore, atosiban could exacerbate inflammation in the context of preterm birth and potentially have an effect on neonatal outcome. With this in mind the future development of OTR antagonists to prevent preterm birth will need to take into account the effects upon differential OTR G-protein coupling.Open Acces

Dirac-Majorana neutrino type conversion induced by an oscillating scalar dark matter

Some properties of a neutrino may differ significantly depending on whether it is Dirac or Majorana type. The type is determined by the relative size of Dirac and Majorana masses, which may vary if they arise from an oscillating scalar dark matter. We show that the change can be significant enough to convert the neutrino type between Dirac and Majorana while satisfying constraints on the dark matter. It predicts periodic modulations in the event rates in various neutrino phenomena. As the energy density and, thus, the oscillation amplitude of the dark matter evolves in the cosmic time scale, the relative size of Dirac and Majorana masses changes accordingly. It provides an interesting link between the present-time neutrino physics to the early universe cosmology including the leptogenesis.Comment: Added more discussions and reference

Invisible dark gauge boson search in top decays using a kinematic method

We discuss the discovery potential of a dark force carrier ($Z'$) of very light mass, $m_{Z'} \lesssim {\cal O}(1-10)$ GeV, at hadron colliders via rare top quark decays, especially when it decays invisibly in typical search schemes. We emphasize that the top sector is promising for the discovery of new particles because top quark pairs are copiously produced at the Large Hadron Collider. The signal process is initiated by a rare top decay into a bottom quark and a charged Higgs boson ($H^\pm$) decaying subsequently into a $W$ and one or multiple $Z'$s. The light $Z'$ can be invisible in collider searches in various scenarios, and it would be hard to distinguish the relevant collider signature from the regular $t\bar{t}$ process in the Standard Model. We suggest a search strategy using the recently proposed on-shell constrained $M_2$ variables. Our signal process is featured by an $\textit{asymmetric}$ event topology, while the $t\bar{t}$ is $\textit{symmetric}$. The essence behind the strategy is to evoke some contradiction in the relevant observables by applying the kinematic variables designed under the assumption of the $t\bar{t}$ event topology. To see the viability of the proposed technique, we perform Monte Carlo simulations including realistic effects such as cuts, backgrounds, detector resolution, and so on at the LHC of $\sqrt{s}=14$ TeV.Comment: Journal-published version, minor modification in table numbers, 19 pages, 6 figures, 2 tables, references adde

Searching for Dark Photons with Maverick Top Partners

In this paper, we present a model in which an up-type vector-like quark (VLQ) is charged under a new $U(1)_d$ gauge force which kinetically mixes with the SM hypercharge. The gauge boson of the $U(1)_d$ is the dark photon, $\gamma_d$. Traditional searches for VLQs rely on decays into Standard Model electroweak bosons $W,Z$ or Higgs. However, since no evidence for VLQs has been found at the Large Hadron Collider (LHC), it is imperative to search for other novel signatures of VLQs beyond their traditional decays. As we will show, if the dark photon is much less massive than the Standard Model electroweak sector, $M_{\gamma_d}\ll M_Z$, for the large majority of the allowed parameter space the VLQ predominately decays into the dark photon and the dark Higgs that breaks the $U(1)_d$ . That is, this VLQ is a `maverick top partner' with nontraditional decays. One of the appeals of this scenario is that pair production of the VLQ at the LHC occurs through the strong force and the rate is determined by the gauge structure. Hence, the production of the dark photon at the LHC only depends on the strong force and is largely independent of the small kinetic mixing with hypercharge. This scenario provides a robust framework to search for a light dark sector via searches for heavy colored particles at the LHC.Comment: 40 pages and 11 figure

Expansion of lymphatic filariasis transmission assessment surveys (TAS) in Oceania as a pragmatic platform for key insights into the epidemiology of communicable diseases including intestinal parasite infections

Introduction: Lymphatic filariasis (LF) and intestinal parasite infections are most prevalent neglected tropical diseases (NTDs) in Oceania. Since 1999, Pacific Programme to Eliminate Lymphatic Filariasis (PacELF) has successfully addressed critical issues and countries are able to stop mass drug administration (MDA) after a decade of the implementation. Transmission assessment surveys (TAS) is a standard methodology to assess whether MDA has reduced the LF prevalence to levels equal to or below the critical cut-off threshold. The aim of this thesis is to present the successful examples of expanding TAS as a pragmatic platform in providing insights into the epidemiology of the key communicable diseases in Oceania. Method: In Wallis Futuna (WAF), grade 2-5 students for the TAS and grade 4-5 for the hepatitis B virus (HBV) infection prevalence assessment were enrolled. The timeliness of vaccination was defined as being vaccinated no later than 4 weeks in comparison to the recommended immunization schedules. In Fiji, all class 1 and 2 students were targeted in 77, 82, and 50 selected schools for the Western TAS 2, Central TAS 1 and Northern Division TAS 2, where same students of 30, 20, and 20 schools were subsampled for stool sample collection. For the diagnosis of intestinal parasite infections, stool samples were examined by coproscopy. In the Eastern, stool samples of class 1-8 students in 24 schools were additionally collected. For the selected stool samples of the Western Division, the Baermann-concentration technique (BC) was added to diagnose strongyloidiasis. All positive samples for intestinal parasites and a systematic sub-sample (every 10th) from the Western Division were transferred to the reference laboratory for real-time PCR. Results: In Wallis Futuna (WAF), TAS 1 had a passing result. The overall HBsAg prevalence was close to 2%. The HBV vaccine coverage for 3 doses was 96%, and the proportion of timeliness was 65%. In the Western Division of Fiji, 7 children in an island out of 3,242 were circulating filariasis antigen (CFA) positive. In the Central and Northern Divisions, the results were all passing, with 2 and no CFA positives, respectively. As for the assessment of intestinal parasite infections in Fiji, 12.4% of children in 3 Divisions were found positive either with Ascaris or hookworm eggs. The overall any intestinal protozoan infection prevalence was 4.8%, and the Giardia infection prevalence was 1.6%. The spatial analysis confirmed that there are still areas with high endemicity at school levels, where Ascaris infection was more clustered in the Central, and Eastern Division and hookworm in the Northern, and hotspots of Giardia infections were clustered around in the urban centres of the Western Division. As for associated factors with STH infections, shoes wearing and main water supply at home from Fiji Water Authority had protective effects. For strongyloidiasis, BC found 1 positive and the overall S. stercoralis infection prevalence via real-time PCR was 3.5 %, from which also higher levels of polyparasitism were reported as well as per species specificity. Discussion and conclusion: The study shows that LF programmes in WAF and in Fiji are on track towards achieving the global goal of LF elimination as a public health problem. For WAF, the HBV infection prevalence is close to meet the regional goal of elimination, but timely vaccination should be more actively encouraged. As for STH infections in Fiji, a low-level of endemicity was observed, but the infections at schools were clustered. Overall any intestinal protozoan infection prevalence was not high, but there were hotspots of Giardia infection clustered, possibly due to contaminated water or foods following the floods caused by a cyclone. An analysis of factors associated STH infections in Fiji suggesting that there is a need to urgently resume preventive chemotherapy for the population at risk as well as to deliver integrated WASH interventions. Given that the estimated prevalence of S. stercoralis infections is endemic (>1 %) in Fiji, some 1.5K children are likely to have strongyloidiasis, implying the needs for curative measures, which was further assessed by molecular technique. In conclusion, LF TAS is a practical platform for assessing epidemiological features of the key communicable diseases in Oceania and should be actively utilized in accessing school-aged children in monitoring and evaluating public health intervention

Gamma EEG Correlates of Haptic Preferences for a Dial Interface

Consumers often develop preferences toward consumer electronics based not only on the visual appearance of a product, but also on its haptic interface. If consumers express a strong haptic preference for a consumer electronic product, they are more likely to purchase it. Hence, it is important to understand how consumers' haptic preference for consumer electronics is formed. Conventional paper-based methods may not provide sufficient information for this purpose, because they provide post-event (i.e., after haptic experience) and environment-dependent (i.e., depending on the manner of asking questions, the person asking the questions, and so on.) data. Therefore, the present study investigated haptic preferences for consumer electronics using neural responses during haptic experiences, which provide the advantage of observing changes while the user is manipulating the product and obtaining environment-independent data. We measured neural responses using non-invasive electroencephalography (EEG). Eighteen volunteers participated in the study and manipulated a haptic dial knob that generates four different haptic profiles; during the manipulation, their EEG signals were recorded. After experiencing different haptic profiles, participants reported their level of preference for each profile. The analysis of EEG revealed that frontal gamma oscillations correlate with the level of haptic preferences, with oscillations becoming stronger with increasing haptic preference. The highest correlation between frontal gamma power and haptic preference was found in the early period of the dial task. Therefore, the frontal gamma oscillation of the EEG may represent a neural correlate of the haptic preference and provides a neural basis for understanding this preference in relation to consumer electronics