5,187 research outputs found
Econometric Forecasting Models for Short Term Natural Rubber Prices
This study presents a number of short-term ex-post forecasts of single equation
model, Multivariate Autoregressive Moving Average (MARMA) model,
simultaneous supply-demand and price system equation model, and Autoregressive
Integrated Moving Average (ARIMA) model, and ARCH-type models of natural
rubber (NR) SMR20 (Standard Malaysia Rubber of grade 20) prices in the world NR
market. The ARCH-type models (Autoregressive Conditional Heteroskedasticity)
used include the GARCH (1,1) (Generalized ARCH) model, EGARCH (1,1) (The
Exponential GARCH) model, PARCH (1,1) (The Power ARCH) and CGARCH (1,1)
(The Component GARCH) model. These were developed for ex-post forecast of
short-term monthly SMR20 prices in the world NR market.
Natural rubber is a vital commodity used in the manufacture of a wide range of rubberbased
products. Over 20 million families are dependent on rubber cultivation for their
livelihood in the world NR market. The years 1997 to 1999 and as well as in the year
2000 were turbulent years for the economies in South-East and East Asia. In 2008, the extremely low prices due to the outbreak of the global recession. It experienced during
these years contributed to price volatility and instability in many countries, especially
rubber smallholders in South East Asia. Moreover, the crude petroleum oil price is an
important component of synthetic rubber. A fall in the crude petroleum oil price relates
to synthetic rubber. It influences a declining share of synthetic rubber in total rubber
consumption, and also a weak currency exchange affects in the NR producing countries
because most commodities are traded in US dollar. This could be a good reason for
taking the current NR price forecasting study. It would be also a direction of short term
NR price movement for policy formulation. Furthermore, the conceptual economic
framework of this study was a good starting point for discussion and perceptive of shortterm
ex-post forecast of NR price forecasting models developed, with the opportunity of
using some of these factors later in the other study for the forecasting of rubber prices.
The model specifications were developed in order to discover the inter-relationships
between NR production, consumption and prices of SMR20, to forecast the NR price of
SMR20 using single equation model, MARMA model, simultaneous system equation of
supply-demand and price forecasting model, ARIMA model, and ARCH-type models, to
analyze and compare the various NR price forecasting models individually in terms of
their comparative price forecasting accuracy and to determine which between the models
are more efficient. The models were utilized using monthly data from January 1990 to
December 2008 as estimation period, providing a total of 228 observations and data was
used as an ex-post forecasts. All data (variables) were tested for unit root test using the
Augmented Dickey-Fuller (ADF) test and the Phillips-Perron (PP) test and were found
to be stationary at first difference. The Granger causality test was tested for the direction
of a Granger causality relationship between two variables
Exploring students' conceptions of the racial and socio-cultural differences in the learning environment of a medical specialty
Study problem
In the education of South African postgraduate medical specialities, various challenges that could have negative impacts on learning are evident. Racial and socio-cultural diversity in South Africa has roots in a previous societal structure that systematically discriminated against particular social groups resulting in significant political, economic and social inequalities between the groupings. With the current processes of transformation underway, the sphere of training postgraduate students in medical specialities reveals visible differences in racial backgrounds between students and consultants at the training centres across the nation, with the majority of consultants being Whites and Indians, whilst the majority of students are Black Africans and a few Indians. The recent high failure rate of the summative exit examination in certain specialities has stimulated a high level of interest into how racial and socio-cultural diversity may have influenced the training and learning of postgraduate students or registrars.
Theoretical framework
In this thesis, a conceptual framework is used that combines dimensions from the theories of Collins (1987), Collins, Brown and Holum (1991) on cognitive apprenticeship, Vygotsky (1978), Lave and Wenger (1991) on socio-cognitive and socio-cultural learning, and Bronfenbrenner’s (1977) theory on Human Ecology. Collectively they posit that relationships are central to the quality of learning and training. The education of postgraduate students, so called registrars or intermediary novices, is structured as personal mentoring in the form of cognitive apprenticeship and their legitimate participation in the departmental Community of Practice. Learning in this context occurs through daily service provision under supervision or mentorship, as well as unscheduled informal discussions (engagement) that reflect socio-cultural learning in which novices and consultant specialists interact socially and academically. This form of learning is dependent on effective mediation and participation, which depends upon understanding, trust and mutual respect in a relationship between the two parties. This relationship could be influenced by factors such as inter-personal differences. Whether the factors translate into socio-cultural differences such as language, culture and social identities, need to be determined.
Aim and objectives
The aim of the study was to explore the conceptions of two student groups, one who had left the specialist programme, and the other who had recently qualified, regarding the nature of racial and socio-cultural diversity in their learning environment, the influences on their learning, and how they responded to them.
Methodology
Using one of the medical speciality disciplines as a focus area, a qualitative enquiry using faceto-face in-depth interviews followed by a thematic analysis of descriptive data was employed. Participants were former students who had either left the formal training programme after being unsuccessful in the summative examination and reached the end of their employment contracts, or those who had recently passed the examination and qualified as junior specialists. The interviews were semi-structured to explore participant’s learning background through schooling, undergraduate and postgraduate studies, with focus on experiences in formative learning through these stages. The participant’s family socio-cultural background was also explored. Data analysis and interpretation were done using a social constructionist epistemology where meanings were co-constructed based on multiple perspectives
Findings and analysis
The following themes were identified from the data analysis: Theme
1: Racial and socio-cultural differences as barriers in learning, with the sub-themes: constructing ‘race’, ‘language’, ‘culture’, and ‘feeling excluded by social status’ as barriers to learning;
Theme 2: Relationships in the learning environment shaping learning, with sub-themes: ‘relationships in the early learning stage’, ‘relationships in undergraduate medicine’, and ‘relationships in postgraduate learning stage of speciality training’;
Theme 3: Challenges in the learning process, with sub-themes as: ‘lack of curricular clarity’, and ‘lack of formative learning structure’;
Theme 4: Resilience, with sub-themes: ‘capacity for adaption’, and ‘the ways in which resilience has been shaped by the micro- and macro-environments’.
The further analysis found the socio-cultural diversity and relationships affecting engagement during formative learning themes to be inter-related, whilst sub-themes race, language, culture and social identities were also inter-connected. The curriculum, formative training, relationships, people’s perspectives and culture of the community were found to be intricate and complex, yet difficulties could still be overcome using certain attributes and skills.
Conclusion
Participants perceived the racial and socio-cultural diversity such as language, culture, personality and socio-economic status in the postgraduate learning environment as barriers to learning. Participants in the group who had qualified were however able to negotiate the diversity by being resilient, adaptable and emotionally mature. These attributes enabled them to navigate difficulties and remain focussed on their goal. An ability to initiate and form relationships with new peers and consultants emerged as an important feature in this group. These findings could hopefully benefit both current and future students and highlight the need to create opportunities for cross-cultural engagement activities in medical speciality training programmes
An Analysis of the Use of Suspense in the Plot Development of Agatha Christie's Tape-measure Murder
Detective fiction is one of the most popular narrative genres today. It includes any story that
has a crime and its solution as a central feature of its plot. In detective fictions, suspense plays
a very important role and it supports the development of the plot. This paper focuses on the use
of suspense in the plot development of the detective short story Tape-measure Murder written
by Agatha Christie. The research was carried out to analyse the phases of the plot and to
classify the types of suspense used in the story and to investigate the impact of suspense on the
plot development of the story. In conduction this research, the phases of the plot were analysed
by applying Pyramid Theory proposed by Gustav Freytag (1900) and the types of suspense
occurred in each phase were classified by applying the classification of suspense proposed by
Nino and Tarmar (2013) and Reedsy (2018). According to the research, the use of horrific
suspense is mostly found to express the fact that each occurance of suspense affects the plot to
be more horrific and shocking. It is found out that the use of suspense in the plot development
provides a satisfactory impact on the readers who love detective fictions as it promotes their
critical thinking and problem-solving skills together with the detectives. It is hoped that
detective stories can be used as classroom materials in teaching English Literature
Responsibilities of Origin Countries for Their Migrant Workers
If migrant workers are well managed and are well protected against abuse and exploitation, they can be of great benefit to both the origin (labour sending) and destination (labour receiving) countries. In reality, the situation is rendered complex by that fact that many do not enter the destination countries legally. While international migration can be a positive experience for migrant workers, many suffer poor working and living conditions, including low wages, unsafe working environments, a virtual absence of social protection, denial of freedom of association and workers‟ rights, discrimination and xenophobia. The origin and destination countries share the responsibilities to protect the rights of migrant workers. But their respective responsibilities are different. Myanmar is a major labour sending country and it is responsibility for protecting the migrant workers. Therefore the government should amend the Law Relating to Overseas Employment, 1999 including strong and practical migration protection policy
Role of Immunopathology in Clinical Course of Malaria: A Review
Malaria is a major health problem in various parts of the world especially affecting the tropical countries. It affects the vital organs causing severe complicated malaria. Clinical syndromes like severe cerebral anaemia, coagulation abnormalities, respiratory distress and severe anaemia can increase the mortality of malaria infected cases. Variation in individual susceptibility and severity and type of clinical presentations of malaria raises the need for study of both the parasite and host immune reactions as well as the contribution of inflammatory cytokines in malaria pathogenesis. This study explored the immunopathological basis and advances of severe malaria and their importance in pathogenesis of malaria and its complications. Previous and ongoing studies indicate that changes in endothelium during the sequestration of parasites in organs causes disruption of endothelial barrier function leading to serious effects of malaria. Parasite and host factors contribute to disturbance of cytokine regulation and escape of parasites from the immune system of the host. Immunopathological changes and dysregulation of cytokine production play central role in pathogenesis and disease severity in malaria
A Study on the Purchase Intention of Agricultural Products by Chinese Consumers in Zhejiang Province on a Live Sales Platform
The purpose of this paper was to explore the attitudes relating to the consumer purchase intentions of live streaming sales and to know the influences on consumers’ final purchase decisions for farming products through live streaming. A quantitative online survey was used to examine consumer purchase intentions for live streaming sales to understand more about their thoughts and behavior regarding agricultural products. The study collected 208 online customer surveys from Chinese nationals, performing a non-probability purposive sampling technique to validate the analysis. The sample size of 208 was calculated based on G*Power. The results show that attitude homophily and influencer professionality in relation to the influencers, impacts the purchase intentions of consumers, suggesting that the consumer decision path involves both affective and internalization processes before the consumer makes a decision to purchase the product. Perceived uncertainty was shown to be a marginal effect whereby consumers are slightly concerned about the quality and price of purchases through live stream shopping. These findings confirm the theory of planned behavior (TPB) by revealing that consumers’ purchase intentions come from their own decision making. Additionally, the study extends the elaboration likelihood model (ELM) by proving that attitude homophily and professionality have a high effect on purchase intentions for live sales. It was found that attitude homophily and professionality are key factors to increase consumers’ trust in products. Therefore, it is suggested that businesses using live stream sales should pay more attention to enhance relatedness for current and potential consumers
Drug interaction s in the constituents of street drug mixture“Nyaope”in South Africa: a mini-review
Nyaope is a unique South African street drug mixture thought to contain illicit drugs and other compounds and is usually inhaled after wrapping in the Cannabis leaf. Despite its illegalization in March 2014, abuse of Nyaope is on the increase. While highly addictive, withdrawal symptoms are very severe, unbearable and drive the user to desperately seek for the next fix. Due to the lack of knowledge in its composition and how the constituents interact with each other, treatment for withdrawal symptoms and rehabilitation has been a challenge. A mini-literature review was done to explore how the major constituents of Nyaope relate to each other in their actions and in their path of breaking down (metabolism). The literature suggests that the inside opiate group, in between opiates and benzodiazepines, in between opiates and cannabis group, in between benzodiazepines and phenobarbitals, and also amongst the minor constituents, there are extensively shared the metabolic pathways which lead to longer plasma half-life in each of these drugs and thus synergistic effects. These shared pathways are via the cytochrome P450 family of enzymes in the liver cell cytoplasm and these enzyme actions are to inactivate or detoxify the drugs or convert them to more water soluble compounds in order to excrete them through the kidneys. Not only sharing the metabolic pathways, but also the actions of these drugs at certain receptors in the brain have either opposing or stimulating effects on one another, making the complex nature of their combined actions. Such findings can explain the unique withdrawal symptom complex of Nyaope, which is important for the clinicians and public health workers who are dealing with the users. Understanding the biochemical and metabolic basis of Nyaope drug interactions provides valuable insight towards the development of withdrawal signs and symptoms which may contribute to the targeted treatment program.Keywords: Nyaope, drugs of abuse, withdrawal symptoms, drug synergy, metabolis
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