PELATIHAN PENERAPAN SISTEM “APARTEMENT” BAGI BUDIDAYA CACING SUTRA PADA KELOMPOK PEMBUDIDAYA IKAN CUPANG DI DESA KAMPUNG BARU, KECAMATAN LANGSA LAMA, KOTA LANGSA

ABSTRAKCacing sutra merupakan pakan hidup yang disukai ikan khususnya larva ikan. Hal ini karena ukurannya yang kecil sehingga mudah dimakan. Kesesuaian pakan hidup yang diberikan akan semakin membuat besar larva ikan hidup dan tumbuh. Tujuan dari kegiatan pengabdian kepada masyarakat ini yaitu membantu mitra untuk meningkatkan hasil produksi ikan cupang dengan pemberian cacing sutra yang dibudidayakan dengan sistem apartement. Metode yang digunakan melalui beberapa tahap, yaitu sosialisasi, pendampingan, monitoring dan evaluasi. Sosialisasi dilakukan untuk memberikan informasi yang lebih jelas tentang maksud dan tujuan tim mengadakan pelatihan penerapan sistem Apartement. Pendampingan dilakukan berupa pembuatan sistem apartemen dan pembuatan pakan cacing sutra dengan menggunakan ampas tahu yang difermentasikan menggunakan larutan EM 4 dan molase selama 3 hari, kemudian pakan siap digunakan. Hasil monitoring dan evaluasi mitra mampu serta terampil membuat wadah sistem apartemen serta pakan cacing sutra dari ampas tahu. Selanjutnya mitra juga sudah sangat faham bagaimana pola kerja dalam melakukan budidaya cacing serta dengan menggunakan sistem apartemen. Kata kunci: cacing sutra; sistem apartement; ikan cupang; desa kampung baru. ABSTRACTTubifex sp. are live food that is preferred by fish, especially fish larvae. This is because of its small size so it is easy to eat. The suitability of the live feed given will make the larger fish larvae live and grow. The purpose of this community service activity is to help partners to increase the production of betta fish by giving silk worms that are cultivated with the apartment system. The method used goes through several stages, namely socialization, mentoring, monitoring and evaluation. The socialization was carried out to provide clearer information about the goals and objectives of the team holding training on the application of the Apartment system. Assistance is provided in the form of building an apartment system and making feed for Tubifex sp. by using tofu dregs which was fermented using EM 4 solution and molasses for 3 days, then the feed was ready for use. The results of monitoring and evaluation of partners are capable and skilled in making apartment system containers and tubifex sp. feed. from tofu dregs. Furthermore, partners also understand very well how the work pattern in cultivating Tubifex sp. using the apartment system. Keywords: tubifex sp. apartment system; Betta splend; kampung baru village.

XÁC ĐỊNH MẬT ĐỘ NUÔI SINH KHỐI THÍCH HỢP VÀ ĐIỀU KIỆN THỨC ĂN TƯƠNG ỨNG CỦA TÔM TIÊN NƯỚC NGỌT, Branchinella thailandensis, LOÀI THỨC ĂN SỐNG TRIỂN VỌNG CHO ƯƠNG NUÔI THỦY SẢN Ở VIỆT NAM

Tôm tiên nước ngọt, Branchinella thailandensis, là một loài giáp xác nước ngọt có triển vọng sử dụng làm thức ăn cho con giống ở giai đoạn ấu trùng tại Việt Nam vì chúng có kích thước nhỏ, khả năng phát triển nhanh và hàm lượng carotenoid cao. Trong nghiên cứu này, B. thailandensis được nghiên cứu để xác định lượng thức ăn và mật độ nuôi thích hợp để nuôi sinh khối trong môi trường nước ngọt. Để đạt được mục tiêu này, 01 thí nghiệm 3 nhân tố được thực hiện: (i) mật độ nuôi tôm tiên với 3 mức (250, 500 và 1000 cá thể/L); (ii) mật độ thức ăn (tảo sống Spirulina platensis) với 3 mức(5 × 105 tế bào/mL, 1 × 106 tế bào/mL và 2 × 106 tế bào/mL); và (iii) mật độ vi khuẩn có lợi Bacillus subtilis với 2 mức (0 và 1 × 103 CFU/ mL). Kết quả nghiên cứu cho thấy, sau 72 giờ, để đạt được tỷ lệ sống cao nhất (68.33% ± 10.4%) và chiều dài tối đa (2.32 ± 0.23 mm), cần áp dụng mật độ thức ăn là 2 × 106 tế bào/mL với mật độ nuôi tối đa cần duy trì là 250 ấu trùng/L và có bổ sung vi khuẩn có lợi (1 × 103 CFU/ mL). Ở điều kiện nuôi này, 01 thí nghiệm 02 nhân tố được thực hiện để khảo sát nồng độ Carotenoid và khả năng lưu trữ vi khuẩn có lợi trong cơ thể của tôm tiên nước ngọt B. thailandensis. Nhân tố mật độ vi khuẩn có lợi B. subtilis với 2 mức (0 và 1 × 103 CFU/mL), nhân tố mật độ tảo với 3 mức: 5 × 105, 1 × 106, và 2 × 106 tế bào/mL. Kết quả nghiên cứu cho thấy B. thailandensis cũng có thể lưu giữ vi khuẩn có lợi trong cơ thể đến ít nhất là 48 giờ sau khi nở và đạt được hàm lượng carotenoid cao hơn hẳn lúc nuôi với nồng độ thức ăn thấp. ABSTRACT Freshwater fairy shrimp, Branchinella thailandensis, is a highly potential live feed for aquaculture species in Viet Nam, especially in their larval stages due to its small size, high growth and high carotenoid content. In this study, we aimed to identify the suitable feeding density and stocking density, which is inappropriate for mass production in freshwater. To attain these objectives, we conducted 01 three-factor experiment: (i) culture density with three levels (250, 500 and 1000 nauplii L-1); (ii) feed (live Spirulina platens) concentration with three levels (5 × 105 cells mL-1, 1 × 106 cells mL-1 and 2 × 106 cells mL-1); and (iii) beneficial bacteria Bacillus subtilis with two levels (0 and 1 × 103 CFU mL-1). The results indicated that after 72hrs, to the highest survival rate (68.33% ± 10.4%) and total length (2.32±0.23 mm) were obtained when shrimps were fed live S. platensis at 2 × 106 cells mL-1 with probiotics at 1 × 103 CFU/ mL, and density at 250 nauplii L-1. Under those culturing conditions, we conducted 01 two-factor experiment: feed (live Spirulina platens) concentration with three levels (5 × 105 cells mL-1, 1 × 106 cells mL-1 and 2 × 106 cells mL-1); and beneficial bacteria Bacillus subtilis with two levels (0 and 1 × 103 CFU mL-1). The results indicated that B. thailandensis could retain B. subtilis internally up to at least 48 hours and obtain significantly higher carotenoid content than at lower feed concentration.

Toward Uncensorable, Anonymous and Private Access Over Satoshi Blockchains

Providing unrestricted access to sensitive content such as news and software is difficult in the presence of adaptive and resourceful surveillance and censoring adversaries. In this paper we leverage the distributed and resilient nature of commercial Satoshi blockchains to develop the first provably secure, censorship resistant, cost-efficient storage system with anonymous and private access, built on top of commercial cryptocurrency transactions. We introduce max-rate transactions, a practical construct to persist data of arbitrary size entirely in a Satoshi blockchain. We leverage max-rate transactions to develop UWeb, a blockchain-based storage system that charges publishers to self-sustain its decentralized infrastructure. UWeb organizes blockchain-stored content for easy retrieval, and enables clients to store and access content with provable anonymity, privacy and censorship resistance properties. We present results from UWeb experiments with writing 268.21 MB of data into the live Litecoin blockchain, including 4.5 months of live-feed BBC articles, and 41 censorship resistant tools. The max-rate writing throughput (183 KB/s) and blockchain utilization (88%) exceed those of state-of-the-art solutions by 2-3 orders of magnitude and broke Litecoin’s record of the daily average block size. Our simulations with up to 3,000 concurrent UWeb writers confirm that UWeb does not impact the confirmation delays of financial transactions.

Terrain surveillance system with drone and applied machine vision

Road accidents are a major contribution to the Annual death rates all over the world. India, ranks first globally in the number of fatalities from road accidents. According to the Ministry of Roads & Transportation, India saw over 440,000 road accidents in 2019. As a result, over 150,000 lives were lost. Poor road conditions contribute to these directly and indirectly. In India, safety standards and conditions of roads are maintained by local bodies in a given area of jurisdiction. While there have been several attempts at improving the quality of roads, weren’t instrumental in giving proper results [42]. A recent study suggested that Artificial Intelligence (AI) might help achieve the goals. Some of the AI applications have had better results when powered with Computer Vision. While computer vision has been previously used to identify faults in roads, it is not widely implemented or made available for public use. Road inspection still largely remains a time-consuming manual task, hindering the maintenance process in most cities. Moreover, being unaware of unattended faults on roads is often the cause of road accidents, especially in rough weather conditions that make it impossible for drivers to visually gauge any dangers on their route. The proposed model uses a transfer-learning approach; using Mask R-CNN in identifying the defects at an instance level segmentation. As adding this, it requires less labelling and an additional mask helps in blocking out extra noise around the images. This paper trains a Mask R-CNN architecture-based model to identify potholes, discontinuous roads, blind spots, speed bumps, and the type of road--gravel, concrete, asphalt, tar, or mud--with a dataset of images obtained from a drone. The model is further trained to create depth maps and friction estimates of the roads being surveyed. Once trained, the model is tested on a drone-captured live feed of roads in Chennai, India. The results, once sufficiently accurate, will be implemented in a practical application to help users assess road conditions on their path.

The influence of temperature and nutrient concentrations on growth rate, biomass, Chlorophyll-a, and biochemical compositions of Tetraselmis suecica (Chlorophyta)

Microalgae have been got high attention due to its potentiality in aquaculture as live feed, and in industries as ingredients for pharmaceutical, cosmetics, and biofuel industries. The objective of this study was to know the optimum culture condition for profuse growth and biochemical composition of Tetraselmis suecica under two parameters: temperature (20°C, 25°C, and 30°C) and modified F/2 medium nutrients concentrations. Culture of group “A” 20°C was categorized as A1 (F/2 stock solution-A; 0.50 ml. L-1 and F/2 stock solution-B; 0.20 ml. L-1), A2 (F/2 stock solution-A; 1. 00 ml L-1 and F/2 stock solution-B; 0.40 ml. L-1) and A3 (F/2 stock solution-A;1.50 ml. L-1 and F/2 stock solution-B; 0.60 ml. L-1). Cultures in 25°C and 30°C were also categorized as groups “B” 25° C (B1, B2, and B3) and “C” 30°C (C1, C2, and C3), respectively. The culture was done for 2 weeks with L:D cycle of 12:12 by using fluorescent light. The highest biomass production was 0.80, 0.64, and 0.45 gL-1 in C2, B3, and A3, respectively. Biochemical analysis showed that protein; 21.92, 20.83, and 18.68 %, lipid; 10.76, 9.42, and 11.71 %, carbohydrate; 38.51, 37.78, and 41.49 %, ash; 15.89, 15.61, and 13.7 %, and moisture; 14.26, 15.02, and 14.42 % in biomass grown of “A”, “B” and “C” culture group, respectively. From the study, it could be said that T. suecic is a eurythermal and mesotrophic habitant microalga which produce high protein and high carbohydrate in low and high temperature, respectively.

Effects of Epibiotic Diatoms on the Productivity of the Calanoid Copepod Acartia tonsa (Dana) in Intensive Aquaculture Systems

We evaluated here the effects of the epibiotic diatom Tabularia sp. on the productivity of the calanoid copepod Acartia tonsa (Dana) for assessing their risk on copepod intensive aquaculture industry for the provision of live feed. In the first experiment, uninfested and intensively infested females were cultivated individually for the assessment of egg production. Intensively infested females appeared to have a significantly lower egg production (5.0–9.0 eggs/female/d) than uninfested females (22.0–26.0 eggs/female/d) during 5 consecutive days. In the second experiment, effects of culture densities on diatom epibiosis were investigated in 9 L cultures at three different densities (200, 400, and 600 ind. L–1). Another culture at higher volume (250 L) and lowest density (200 ind. L–1) was also carried out to test the effect of culture volume on diatom epibiosis. The infestation rate (%), infestation intensity (ratio of surface diatom coverage levels, classified as levels 0–3) and daily egg harvest rate (number of harvested eggs per day per liter) were evaluated among the four culture populations. The copepods had higher infestation rate (53.69–60.14%) and intensity rate (high ratios at level 2 and 3) when the densities were increased from 200 ind./L to 400 and 600 ind./L. Although egg harvest increased with increasing culture density, it seemed that the diatom-infested A. tonsa population reach a saturated egg production when the density was higher than 400 ind./L. Nevertheless, the differences of culture volumes (250 and 9 L) appeared to be not to have any effect when the copepods were cultivated at the same density (200 ind./L). This study reveals for the first time that the epibiosis of the diatom Tabularia sp. reduces the individual egg production, and egg harvest rate in high-density culture of the copepod A. tonsa. Our findings implicate that diatom epibiosis should be avoid in copepod intensive culture systems.