The Humoral Response against <i>Salmonella</i> Typhi Protein Antigens During Acute, Convalescent, and Chronic Typhoid Fever

Enteric (typhoid) fever is a life-threatening disease caused by the Salmonella enterica subspecies enterica serovars Typhi (S. Typhi) and Paratyphi A, B, and C (S. Paratyphi A, B, and C). The disease still causes major public health problems in low- and middle-income countries, principally in Asia and Africa. The increasing frequency of multi-drug resistant (MDR) and extended-drug resistant isolates (XDR) of S. Typhi and an increasing incidence of S. Paratyphi A mean that the international dynamics of enteric fever are changing. These changes add urgency to the demand for more efficient enteric fever control campaigns. The aim of this thesis was to assess control measures for enteric fever in Vietnam and to develop techniques that can be used as further control methods. I firstly systemically reviewed retrospective information regarding enteric fever in Vietnam and combined these data with data on economic development. This investigation revealed that national economic growth, the provision of improved quality drinking water, and better sanitation were likely the greatest contributors to the decline and ultimate elimination of enteric fever in Vietnam. My work then evaluated the serodiagnostic potential of a panel of novel S. Typhi protein antigens and the Vi capsular polysaccharide (Vi) in a group of patients with febrile diseases in Bangladesh. These data demonstrated the utility of serology for typhoid diagnostics when exploiting a combination of Vi and at least one protein antigen. I then assessed the acquisition of antibody against typhoid toxin during natural S. Typhi and S. Paratyphi A infections and measured the capability of these antibodies to neutralise the toxin. The data provided supporting evidence for generating an antitoxin treatment for enteric fever (caused by both S. Typhi and S. Paratyphi A), and potentially encourages the use of typhoid toxin in vaccine formulations. Within the scope of searching for vaccine novel candidates, my work further identified a panel of immunogenic antigens shared between S. Typhi and S. Paratyphi A that can stimulate an antibody response which can instigate bactericidal killing during natural infection. Finally, by exploiting the unique immunological profiles of S. Typhi carriers (cytokines and antibody), I developed a method of identifying S. Typhi carriers and estimating the prevalence of S. Typhi carriage in a typhoid endemic population. My findings will potentially lead to the development of novel enteric fever control strategies. I conclude that improved case detection and widespread vaccination campaigns using polyvalent Salmonella vaccines should be initiated for reducing the burden of enteric fever in endemic areas

Poverty Targeting and Impact of a Governmental Micro-credit Program in Vietnam

It is argued that without collateral the poor often face binding borrowing constraints in the formal credit market. This justifies a micro-credit program, which is operated by the Vietnam Bank for Social Policies to provide the poor with preferential credit. This paper examines poverty targeting and impact of the micro-credit program. It is found that the program is not very pro-poor in terms of targeting. Among the participants, the non-poor account for a larger proportion of loans. The non-poor also tend to receive larger amounts of credit compared to the poor. However, the program has positive impact on poverty reduction of the participants. This positive impact is found for all the three Foster-Greer-Thorbecke poverty measures.Micro-credit, poverty, poverty targeting, impact evaluation, instrumental variables, fixed-effect model

Integral manifolds for semilinear evolution equations and admissibility of function spaces

We prove the existence of integral (stable, unstable, and center) manifolds for the solutions to a semilinear integral equation in the case where the evolution family (U(t, s)) t≥s has an exponential trichotomy on a half line or on the whole line, and the nonlinear forcing term f satisfies the φ-Lipschitz conditions, i.e., where φ(t) belongs to some classes of admissible function spaces. Our main method is based on the Lyapunov–Perron methods, rescaling procedures, and the techniques of using the admissibility of function spaces.Доведено iснування iнтегральних (стiйких, нестiйких, центральних) многовидiв для розв’язкiв напiвлiнiйного iнтегрального рiвняння у випадку, коли сiм’я еволюцiй (U(t,s))tleqs має експоненцiальну трихотомiю на пiвосi або на всiй осi, а нелiнiйний збурюючий член f задовольняє φ-лiпшицевi умови, тобто належить до деяких класiв допустимих просторiв функцiй. Наш основний метод базується на методах Ляпунова – Перрона, процедурах перемасштабування та технiцi застосування допустимостi просторiв функцiй

BIM-based Competitive Advantages and Competitive Strategies for Construction Consultancy SMEs: A Case Study in Vietnam

Building Information Modelling (BIM) has been proven as an innovative approach to bring values to construction projects as well as stakeholders, including construction consultancy firms. BIM adoption could assist construction consultancy Small and Medium-sized Enterprise (SMEs) in enhancing their competitive capability. Using a case study with a pioneer BIM service providers &nbsp;which is an SME in Vietnam (the Consultant), the paper explores the core competences for delivering BIM services in relation with potential competitive advantages. Four typical BIM market segments have been discovered, which include: i) BIM strategic services, (ii) BIM services, (iii) BIM-enabled services, and (iv) BIM tools development. Exploring six BIM cases, the realized core competences of the Consultant which are reported in the paper include the BIM-related skillful human resources (both in-house and from external), BIM know-hows, reputation, and also the benefits from a BIM network that the Consultant established as an outcome of a granted BIM research project. Focusing on only the first three market segments, the Consultant has taken advantage of their core competences to deliver differentiation and focus strategies to compete and generate competitive advantages. Cost leadership strategies were not very successful in the case study due to that the economies of scale could not be met; however, they can be considered with the provision of BIM-enabled services, when BIM services are delivered together with other consultancy and/or construction services

Open-Vocabulary Affordance Detection in 3D Point Clouds

Affordance detection is a challenging problem with a wide variety of robotic applications. Traditional affordance detection methods are limited to a predefined set of affordance labels, hence potentially restricting the adaptability of intelligent robots in complex and dynamic environments. In this paper, we present the Open-Vocabulary Affordance Detection (OpenAD) method, which is capable of detecting an unbounded number of affordances in 3D point clouds. By simultaneously learning the affordance text and the point feature, OpenAD successfully exploits the semantic relationships between affordances. Therefore, our proposed method enables zero-shot detection and can be able to detect previously unseen affordances without a single annotation example. Intensive experimental results show that OpenAD works effectively on a wide range of affordance detection setups and outperforms other baselines by a large margin. Additionally, we demonstrate the practicality of the proposed OpenAD in real-world robotic applications with a fast inference speed (~100ms). Our project is available at https://openad2023.github.io.Comment: Accepted to The 2023 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2023

Open-Vocabulary Affordance Detection using Knowledge Distillation and Text-Point Correlation

Affordance detection presents intricate challenges and has a wide range of robotic applications. Previous works have faced limitations such as the complexities of 3D object shapes, the wide range of potential affordances on real-world objects, and the lack of open-vocabulary support for affordance understanding. In this paper, we introduce a new open-vocabulary affordance detection method in 3D point clouds, leveraging knowledge distillation and text-point correlation. Our approach employs pre-trained 3D models through knowledge distillation to enhance feature extraction and semantic understanding in 3D point clouds. We further introduce a new text-point correlation method to learn the semantic links between point cloud features and open-vocabulary labels. The intensive experiments show that our approach outperforms previous works and adapts to new affordance labels and unseen objects. Notably, our method achieves the improvement of 7.96% mIOU score compared to the baselines. Furthermore, it offers real-time inference which is well-suitable for robotic manipulation applications.Comment: 8 page

Language-driven Scene Synthesis using Multi-conditional Diffusion Model

Scene synthesis is a challenging problem with several industrial applications. Recently, substantial efforts have been directed to synthesize the scene using human motions, room layouts, or spatial graphs as the input. However, few studies have addressed this problem from multiple modalities, especially combining text prompts. In this paper, we propose a language-driven scene synthesis task, which is a new task that integrates text prompts, human motion, and existing objects for scene synthesis. Unlike other single-condition synthesis tasks, our problem involves multiple conditions and requires a strategy for processing and encoding them into a unified space. To address the challenge, we present a multi-conditional diffusion model, which differs from the implicit unification approach of other diffusion literature by explicitly predicting the guiding points for the original data distribution. We demonstrate that our approach is theoretically supportive. The intensive experiment results illustrate that our method outperforms state-of-the-art benchmarks and enables natural scene editing applications. The source code and dataset can be accessed at https://lang-scene-synth.github.io/.Comment: Accepted to NeurIPS 202

Impact of Micro-credit on Poverty and Inequality: The Case of the Vietnam Bank for Social Policies

While the provision of subsidized loans through the VBSP forms a cornerstone of Vietnam’s antipoverty policy, little is known on the impact of these preferential loans. In this paper, we use fixed effect regression to estimate the average effect of the program on income and expenditures of participating households, and subsequently assess the impact of the program on poverty and inequality. Our estimates indicate that the VBSP was quite effective. Participation on average seemed to have increased household income and expenditures by about thirty percent of the value of the loan, and an increase in loan size would have a similar effect. Despite that only one third of loans reaches households who are actually poor, our computations indicate that the program decreased the head count of poverty for its participants by almost four percentage points. Similarly, the program decreased the poverty gap index and the poverty-severity index by almost twenty percent. The impact on Vietnam’s inequality was significant but small, which is not surprising because of the yet limited outreach of seven percent of the rural population