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Currently, on-site diesel firefighting pump systems are significantly necessary for high-rise buildings. This study presents a process for designing diesel fire pump systems for high-rise buildings using AVL BOOST software associated with mechanical calculations. The Kirloskar CPHM 80/32 pump and DESSUN 4DSP-75 diesel engine were selected based on preliminary calculations to match the requirements of Vietnamese standards for a 79-meter building. AVL BOOST software has been used to simulate the full load performance characteristic of the engine; then, a partial load characteristic is determined for the adequate pump that requires input power at a rated speed of about 2975 rpm. The transmission consists of the propeller drive, and flanges were designed to connect the engine and pump. The findings show that utilizing AVL BOOST software is considerably helpful in determining the engine's partial load characteristics, saving time and costs. This study contributes a foundation for practical research to calculate and design the firefighting pump mechanical systems in high-rise buildings.

Lymphatic research has progressed rapidly in recent years. Though lymphatic dysfunction has been found in a wide array of disorders from transplant rejection to cancer metastasis, to date, there is still little effective treatment for lymphatic diseases. The cornea offers an optimal site for lymphatic research due to its accessible location, transparent nature, and lymphatic-free but inducible features. However, it still remains unknown whether lymphatic valves exist in newly formed lymphatic vessels in the cornea, and how this relates to an inflammatory response. In this study, we provide the first evidence showing that lymphatic valves were formed in mouse cornea during suture-induced inflammation with the up-regulation of integrin alpha 9. The number of corneal valves increased with the progression of inflammatory lymphangiogenesis. Moreover, we have detected lymphatic valves at various developmental stages, from incomplete to more developed ones. In addition to defining the average diameter of lymphatic vessels equipped with lymphatic valves, we also report that lymphatic valves were more often located near the branching points. Taken together, these novel findings not only provide new insights into corneal lymphatic formation and maturation, but also identify a new model for future investigation on lymphatic valve formation and possibly therapeutic intervention.

Due to the strong development of agricultural and industrial activities in this day and age, the widespread use of fossil fuels has caused the concentration of greenhouse gases in the atmosphere to significantly increase. With a high concentration of greenhouse gases comes an increase in the temperature of the Earth, which contributes to the acceleration of climate change. This paper presents a remote sensing technique capable of determining atmospheric CO2 concentrations from spectral radiation values obtained by satellite images, thereby simulating the distribution of CO2 concentrations over the entire city of Ho Chi Minh. This study uses two data sources: Greenhouse Gases Observing Satellite (GOSAT) and Moderate Resolution Imaging Spectroradiometer (MODIS) images. Calculation results show that throughout the city the average CO2 concentration in the first 6 months of 2019 has a minimum value of 360 ppm and maximum value of 410 ppm; these values change monthly and depend on the type of surface land cover. The highest concentration of CO2 is found over areas of water, bare land, and urban land. On the contrary, over green areas and forests, the CO2 concentration values are about 360-370 ppm. These results are a suitable reference available to support strategic planners focused on CO2 emission management, and suggest that expanding urban vegetation to increase the absorption capacity of carbon will contribute to the reduction of the greenhouse effect.

This study investigates various partial load characteristics of a diesel engine, including brake specific fuel consumption, torque, and power, to get insight into these performances in practice. Firstly, these characteristics were experimentally examined with approximate 25, 50, 75, and 85 % fuel rack settings at 900–2400 rpm engine speeds. Then, more operating modes were investigated to build characteristics corresponding to constant fuel quantity per engine cycle. The results indicate that the practical partial load characteristics significantly differ from the theory of full-load characteristics since the fuel quantity per cycle varies even though the rack is fixed. Especially at low loads, the fuel quantity per cycle increases enormously with engine speed due to the significant influence of pressure waves. Hence, torque and power increase continuously, making it challenging to control the engine operation. In contrast, because the reduction in fuel viscosity and pump efficiency balances the pressure wave effects at high loads, fuel quantity per cycle remains relatively constant, making the characteristics more similar to the theory. Besides, if fuel quantity per cycle is kept constant, the trends in partial load curves follow the theory, which can be approximately predicted. These findings reveal that considering fuel quantity per cycle is significant when studying diesel engine partial loads, notably at low loads. The study contributes a vital basis for further investigating and modeling the partial characteristics of diesel engines. Also, it is a crucial reference for estimating the suitable working conditions of engine-driven systems in practice.

The drivetrain is an essential component of the diesel firefighting pump system, affecting the engine's operating mode, power, economy, and environment. This study proposes a process to design and optimize the transmission ratio and working load of the diesel firefighting pump system. AVL BOOST software was used to model the 6-cylinder diesel engine and analyze the performance characteristics at its partial loads as parameters for finding the optimal transmission ratio of the drivetrain. The optimal transmission ratio determined in this work is 1:1.2, along with engine partial load mode of 57 %, which can improve the engine's fuel efficiency by 8 % compared to the 1:1 transmission ratio. A belt drive is calculated and designed to transfer power between the engine and the firefighting pump. The optimal drivetrain transmission ratio and engine working mode can increase the fuel economy and lifespan of the engine, decrease the engine's maintenance costs, and reduce environmental pollution and greenhouse gases.

Abstract Background The duplex kidney is one of the common congenital anomalies of the kidney and urinary tract. We present two cases of renal tumor accompanied with ipsilateral duplex kidney. The image of the tumor, renal artery system and collecting system were rendered by AI software (Fujifilm’s Synapse® AI Platform) to support the diagnosis and surgical planning. Case presentation Two Vietnamese patients (a 45-year-old man and a 54-year-old woman) with incidental cT1 renal cell carcinoma (RCC) were confirmed to have ipsilateral duplex kidneys by 3D reconstruction AI technique. One patient had a Renal score 9ah tumor of left kidney while the other had a Renal score 9 × tumor of right kidney in which a preoperative CT scan failed to identify a diagnosis of duplex kidney. Using the Da Vinci platform, we successfully performed robotic partial nephrectomy without any damage to the collecting system in both cases. Conclusion RCC with duplex kidneys is a rare condition. By utilizing a novel AI reconstruction technique with adequate information, two patients with RCC in duplex kidneys were successfully performed robotic partial nephrectomy without complication.

With the explosion of urbanization, more and more small residential areas with high population density, tiny houses, and narrow roads are formed. As a result, it is challenging for large fire engines to penetrate these areas in the event of a fire incident. In this paper, a compact firefighting vehicle was designed based on the SNAPPER LT140H331KV lawn mower. The vehicle is equipped with a water sprayer system and a folding frame water tank. The water sprayer system transmits power from the lawn mower transmission’s power take-off shaft via the belt and chain drive, which can spray water at a height of about 13 m with a flow rate of 38 L/min. The 500-liter folding frame water tank has a rectangular shape that can be folded and dragged as a trailer. The water sprayer system and folding frame water tank not only have a simple, compact structure but also do not affect the lawn mowing function. This fire truck has a maximum speed of about 15 km/h and can move in a minimal road width of only 1.3 m, which is accommodation for residential areas within a 1÷2 km radius with narrow roads, high density of population and houses in least developed and developing countries (e.g., Vietnam, Laos, Cambodia), where the normal fire engines are difficult to access in time. Besides, the vehicle can be used for watering and spraying pesticides on gardens and small premises. The study has proposed a valuable solution to take advantage of vehicle functions to improve their convenience and usefulness.

Abstract Introduction In this case report, we demonstrate our technique of a retroperitoneal laparoscopic heminephrectomy for a T1b right hilar tumor in a horseshoe kidney. Case presentation A 77-year-old Vietnamese woman presented to the hospital because of right flank pain. On presentation, her serum creatinine was 0.86 mg/dL and glomerular filtration rate was 65.2 mL/minute/1.73 m2. According to her renal scintigraphy, glomerular filtration rates of the right and left moieties were 24.2 and 35.5 mL/minute, respectively. Computed tomography imaging demonstrated a 5.5 × 5.0 cm solid hilar mass with a cT1bN0M0 tumor stage was in the right moiety. After discussion, the patient elected a minimally invasive surgery to treat her malignancy. The patient was placed in a flank position. We used Gaur’s balloon technique to create the retroperitoneal working space, and four trocar ports were planned for operation. Three arteries were dissected, including two arteries feeding the right moiety, one artery feeding the isthmus, and one vein, which was clipped and divided by Hem-o-lok. The isthmusectomy was performed with an Endostapler. Consequently, the ureter was clipped and divided. Finally, the whole right segment of the horseshoe kidney was mobilized and taken out via the flank incision. Results The total operative time was 250 min with an estimated blood loss of 200 mL. The patient's serum creatinine after surgery was 1.08 mg/dL, and glomerular filtration rate was 49.47 mL/minute/1.73 m2. The patient was discharged on postoperative day #4 without complication. Final pathologic examination of the tumor specimen revealed a Fuhrman grade II clear cell renal cell carcinoma, capsular invasion, with negative surgical margins. After a three-month follow-up, the serum creatinine was 0.95 mg/dL, and glomerular filtration rate was 57.7 mL/minute/1.73 m2. Local recurrence or metastasis was not detected by follow-up computed tomography imaging. Conclusions Retroperitoneal laparoscopic heminephrectomy is a safe and feasible technique for patients with renal cell carcinoma in a horseshoe kidney and may be particularly useful in low income settings without access to robotic technology.

Background: Oxidative stress-induced retinal degeneration is among the main contributing factors of serious ocular pathologies that can lead to irreversible blindness. αB-crystallin (cry) is an abundant component of the visual pathway in the vitreous humor, which modulates protein and cellular homeostasis. Within this protein exists a 20 amino acid fragment (mini-cry) with both chaperone and antiapoptotic activity. This study fuses this mini-cry peptide to two temperature-sensitive elastin-like polypeptides (ELP) with the goal of prolonging its activity in the retina. Methods: The biophysical properties and chaperone activity of cry-ELPs were confirmed by mass spectrometry, cloud-point determination, and dynamic light scattering ’DLS’. For the first time, this work compares a simpler ELP architecture, cry-V96, with a previously reported ELP diblock copolymer, cry-SI. Their relative mechanisms of cellular uptake and antiapoptotic potential were tested using retinal pigment epithelial cells (ARPE-19). Oxidative stress was induced with H2O2 and comparative internalization of both cry-ELPs was made using 2D and 3D culture models. We also explored the role of lysosomal membrane permeabilization by confocal microscopy. Results: The results indicated successful ELP fusion, cellular association with both 2D and 3D cultures, which were enhanced by oxidative stress. Both constructs suppressed apoptotic signaling (cleaved caspase-3); however, cry-V96 exhibited greater lysosomal escape. Conclusions: ELP architecture is a critical factor to optimize delivery of therapeutic peptides, such as the anti-apoptotic mini-cry peptide; furthermore, the protection of mini-cry via ELPs is enhanced by lysosomal membrane permeabilization.

Today’s technology still limits the accessing to 2D information (images, graphics, charts, maps, paintings, etc.) for visually impaired people (VIP). Existing solutions for human-machine interfaces are expensive and have yet to be available to the many. Therefore, we propose a novel and inclusive haptic architecture to access and interact with 2D data, relying on the force-feedback principle, and named Force-Feedback Tablet (F2T). The F2T’s architecture is based on a flat thumbstick mounted on a 2D actuated support, enabling force feedback effects on user’s finger. The flat thumbstick measures the user’s intended movements independently from mobile support’s actual movements, enabling highly interactive effects, static and dynamic effects, or guidances. Moreover, the mechanical structure does not need to be backdrivable, simplifying the motion control, and reducing the costs of the device. Finally, the F2T architecture allows designing lightweight, compact and scalable devices. To validate and demonstrate the relevance of the F2T architecture, we present two lightweight prototypes. Two series of preliminary tests with VIP and blindfolded participants confirmed the system’s effectiveness at providing shape and spatial layout understanding. Results obtained during the evaluation are encouraging with high recognition rates.

This paper introduces the design of a novel indoor and outdoor mobility assistance system for visually impaired people. This system is named the MAPS (Mobility Assistance Path Planning and orientation in Space), and it is based on the theoretical frameworks of mobility and spatial cognition. Its originality comes from the assistance of two main functions of navigation: locomotion and wayfinding. Locomotion involves the ability to avoid obstacles, while wayfinding involves the orientation in space and ad hoc path planning in an (unknown) environment. The MAPS architecture proposes a new low-cost system for indoor–outdoor cognitive mobility assistance, relying on two cooperating hardware feedbacks: the Force Feedback Tablet (F2T) and the TactiBelt. F2T is an electromechanical tablet using haptic effects that allow the exploration of images and maps. It is used to assist with maps’ learning, space awareness emergence, path planning, wayfinding and effective journey completion. It helps a VIP construct a mental map of their environment. TactiBelt is a vibrotactile belt providing active support for the path integration strategy while navigating; it assists the VIP localize the nearest obstacles in real-time and provides the ego-directions to reach the destination. Technology used for acquiring the information about the surrounding space is based on vision (cameras) and is defined with the localization on a map. The preliminary evaluations of the MAPS focused on the interaction with the environment and on feedback from the users (blindfolded participants) to confirm its effectiveness in a simulated environment (a labyrinth). Those lead-users easily interpreted the system’s provided data that they considered relevant for effective independent navigation.

In Vietnam, vaccination has played a crucial role in the national strategy for the prevention and control of H5 highly pathogenic avian influenza (HPAI). This study aimed to evaluate antibody responses of immunologically naïve domestic ducks to H5N1 avian influenza vaccine currently used in the national mass vaccination program of Vietnam. Blood samples of 166 ducks reared on smallholder farms were individually collected at three sampling time points, namely, right before vaccination, 21 days after primary vaccination, and 21 days after booster vaccination. Vaccine-induced antibody titers of duck sera were measured by the hemagglutination inhibition assay. Temporal differences in mean antibody titers were analyzed using the generalized least-squares method. No sampled ducks showed anti-H5 seropositivity pre-vaccination. The geometric mean titer (GMT) of the vaccinated ducks was 5.30 after primary vaccination, with 80% of the vaccinated ducks showing seropositivity. This result indicates that the immunity of duck flocks met the targets of the national poultry H5N1 HPAI mass vaccination program. GMT and seropositive rates of the ducks were 6.48 and 96.3%, respectively, after booster vaccination, which were significantly higher than those after primary vaccination. Flock-level seroprotection rate significantly increased from 68% to 84.7%, whereas variability in GMT titers decreased from 34.87% to 26.3%. This study provided important information on humoral immune responses of ducks to the currently used H5N1 vaccine under field conditions. Our findings may help guide veterinary authorities in planning effective vaccine protocols for the prevention and control of H5N1 in the target poultry population.

Health information systems to monitor vaccine safety are used in industrialized countries to detect adverse medical events related to vaccinations or to prove the safety of vaccines. There are no such information systems in the developing world, but they are urgently needed. A large linked database for the monitoring of vaccine-related adverse events has been established in Khanh Hoa province, Viet Nam. Data collected during the first 2 years of surveillance, a period which included a mass measles vaccination campaign, were used to evaluate the system. For this purpose the discharge diagnoses of individuals admitted to polyclinics and hospitals were coded according to the International Classification of Diseases (ICD)-10 guidelines and linked in a dynamic population database with vaccination histories. A case-series analysis was applied to the cohort of children vaccinated during the mass measles vaccination campaign. The study recorded 107 022 immunizations in a catchment area with a population of 357 458 and confirmed vaccine coverage of 87% or higher for completed routine childhood vaccinations. The measles vaccination campaign immunized at least 86% of the targeted children aged 9 months to 10 years. No medical event was detected significantly more frequently during the 14 days after measles vaccination than before it. The experience in Viet Nam confirmed the safety of a measles vaccination campaign and shows that it is feasible to establish health information systems such as a large linked database which can provide reliable data in a developing country for a modest increase in use of resources.

A planar antenna for ultra-wideband (UWB) applications covering the 3.1–10.6 GHz range has been designed as a test bed for efficiency measurements of antennas manufactured using polymer conductors. Two types of conductive polymers, PEDOT and PPy (polypyrrole), with very different thicknesses and conductivities have been selected as conductors for the radiating elements. A comparison between measured radiation patterns of the conductive polymers and a copper reference antenna allows to estimate the conductor losses of the two types of conductive polymers. For a 158 μm thick PPy polymer, an efficiency of almost 80% can be observed over the whole UWB spectrum. For a 7 μm thick PEDOT layer, an average efficiency of 26.6% demonstrates, considering the room for improvement, the potential of this type of versatile materials as flexible printable alternative to conductive metallic paints. The paper demonstrates that, even though the PEDOT conductivity is an order of magnitude larger than that of PPy, the thicker PPy layer leads to much higher efficiency over the whole UWB frequency range. This result highlights that high efficiency can be achieved not only through high conductivity, but also through a sufficiently thick layer of conductive polymers.