160 research outputs found
MARICULTURE DEVELOPMENT IN INDONESIA: Prospects and Constraints
Mariculture is an important component of Indonesian fisheries and aquaculture production, directly contributing an estimated US$ 320 million in 2008. Because most mariculture production is focussed on producing for export markets, mariculture production is an important source of foreign earnings for the Indonesian economy. This paper reviews the current status and prospects for continuing development of mariculture in Indonesia. Currently the major mariculture commodity in Indonesia is seaweed for carrageenan production. Seaweed production accounts for 98% of total Indonesian mariculture production and 84% of value. The other major commodity groups are marine finfish and pearl oysters. Commodities being developed for mariculture in Indonesia include abalone and spiny lobsters. Prospects for continued development of mariculture in Indonesia appear positive. Indonesia has several advantages for mariculture development, including many potential mariculture sites, a stable tropical climate, and does not suffer from cyclonic storms. The Government of Indonesia is planning to increase aquaculture production substantially over the next four years, including mariculture production. Globally, demand for seafood products is expanding due to increasing population and increased per capita consumption of fish products. Constraints to the continued development of mariculture in Indonesia include: limited seed supply, particularly of species which cannot be economically produced in hatcheries, such as spiny lobsters; need to develop more efficient production systems for some marine finfish; the need to improve environmental sustainability by improving feeds and reducing environmental impacts; and market issues relating to environmental sustainability
Organic Geochemical and Petrographic Analysis of Pure Macerals from the Ohio Shale
Recent advances now permit the separation of coal into constituent macerals of high purity using density gradient centrifugation (DGC). With the availability of pure macerals, the chemical structure of each can be investigated separately, without the interactive interference of the other macerals or mineral matter. The present study is a preliminary effort applying these methods to the study of oil shale kerogen.
We have used a sample from the Huron Member of the Upper Devonian Ohio Shale from Logan County, Ohio. Whole rock petrographic examination revealed intact Tasmanites, telalginite of unknown derivation and a weakly fluorescing matrix. Pyrite is abundant, including framboidal and euhedral pyrite imbedded within macerals. The kerogen concentrate was subjected to DGC. The resulting profile shows a single, broad main peak, consisting of mixed telaginite, amorphinite and rare vitrinite. Variable amounts of entrapped minerals apparently account for the broad range of density within the peak, with the organic assemblage being fairly consistent. In future work, it is recommended that the kerogen be micronized prior to DOC to permit a cleaner separation.
In order to investigate the chemistry of macerals, pyrolysis is preferred over simple extraction, since soluble native bitumen is mobile and may migrate from the maceral of origin into a neighboring one, acting as a natural contaminant. Pyrolysis techniques assure that the data reflect the nature of indigenous material only. The Ohio Shale kerogen and 4 DGC fractions were subjected to micro-scale, anhydrous, in vitro pyrolysis, followed by GCMS of the saturate and aromatic LC fractions of the pyrolyzate. The 4 DGC fractions are nearly identical in both their saturate and aromatic molecular distributions, consistent with the petrographic observations. To further demonstrate the efficacy of the method, a pure sporinite isolated from a coal in the Pennsylvanian Brazil Formation of Indiana was also analyzed. The sporinite pyrolyzate can readily be distinguished from that of the Ohio Shale alginite by the distributions of n-alkanes, isoprenoids, phyllocladane derivatives, extended tricyclic terpanes, hopanes, moretanes, steranes, alkylbenzenes and thiophene derivatives. Py-LC-GCMS is an effective and versatile characterization tool, as it provides a great number of molecular parameters
Improved hatchery and grow-out technology for marine finfish aquaculture in the Asia–Pacific region
This project focussed on improving marine finfish aquaculture production in the Asia-Pacific region by focussing on key constraints: improving hatchery technology to improve the availability of seedstock; evaluating the nutritional needs of groupers to support the development of compounded pellet diets; and improving communication and coordination of marine finfish aquaculture research and development activities in the Asia-Pacific region
Cisplatin effects on the human fetal testis - establishing the sensitive period for (pre)spermatogonial loss and relevance for fertility preservation in pre-pubertal boys
BACKGROUND: Exposure to chemotherapy during childhood can impair future fertility. Studies using in vitro culture have shown exposure to platinum-based alkylating-like chemotherapy reduces the germ cell number in the human fetal testicular tissues. We aimed to determine whether effects of exposure to cisplatin on the germ cell sub-populations are dependent on the gestational age of the fetus and what impact this might have on the utility of using human fetal testis cultures to model chemotherapy exposure in childhood testis. METHODS: We utilised an in vitro culture system to culture pieces of human fetal testicular tissues (total n=23 fetuses) from three different gestational age groups (14-16 (early), 17-19 (mid) and 20-22 (late) gestational weeks; GW) of the second trimester. Tissues were exposed to cisplatin or vehicle control for 24 hours, analysing the tissues 72 and 240 hours post-exposure. Number of germ cells and their sub-populations, including gonocytes and (pre)spermatogonia, were quantified. RESULTS: Total germ cell number and number of both germ cell sub-populations were unchanged at 72 hours post-exposure to cisplatin in the testicular tissues from fetuses of the early (14-16 GW) and late (20-22 GW) second trimester. In the testicular tissues from fetuses of mid (17-19 GW) second trimester, total germ cell and gonocyte number were significantly reduced, whilst (pre)spermatogonial number was unchanged. At 240 hours post-exposure, the total number of germ cells and that of both sub-populations was significantly reduced in the testicular tissues from fetuses of mid- and late-second trimester, whilst germ cells in early-second trimester tissues were unchanged at this time-point. CONCLUSIONS: In vitro culture of human fetal testicular tissues can be a useful model system to investigate the effects of chemotherapy-exposure on germ cell sub-populations during pre-puberty. Interpretation of the results of such studies in terms of relevance to later (infant and pre-pubertal) developmental stages should take into account the changes in germ cell composition and periods of germ cell sensitivity in the human fetal testis
Diversification of brackishwater aquaculture in Indonesia: tilapia culture in Aceh
Traditional brackishwater aquaculture in Indonesia focuses on production of shrimp and milkfish. However, since the 1990’s production of shrimp, particularly Penaeus monodon, has become problematic because ofthe prevalence of white-spot disease. Crop losses due to white-spot disease have limited production of P. monodon in traditional tambak throughout Indonesia. Because of this, many tambak have fallen into disuse, or their use islimited. In response, we are developing and trialling diversification options for tambak farmers in Aceh and South Sulawesi. Alternative production options that we are evaluating include Nile tilapia (ikan nila) and soft-shell crab(kepiting lunak) in Aceh, and Nile tilapia, swimming crab (rajungan) and rabbitfish (baronang) in South Sulawesi. In Aceh our main focus has been on Nile tilapia (Oreochromis niloticus) culture, either alone or co-cultured with milkfish (Chanos chanos). We have undertaken trials with farmers in Samalanga and Jangka (Kab. Bireuen) and Banda Mulia (Kab. Aceh Tamiang). Overall, our trials have shown that tilapia will grow and survive well at salinities below 20 ppt. Above 20 ppt, growth rate is reduced and the fish are prone to bacterial disease. At salinities above 20 ppt, milkfish (bandeng) perform better in ponds than tilapia. Our trials in Aceh have demonstrated that Nile tilapia can provideincome to farmers comparable with shrimp culture. Out of a total of 22 trials to date, 9 ponds (41%) have met or exceeded our reference profitability of IDR 1–5 million per hectare per crop. Fourteen ponds (64%) have been‘profitable’, i.e. have generated positive economic returns. This figure is similar to the profitability figure for traditional shrimp ponds (64–73%), indicating that Nile tilapia culture in brackishwater ponds provides economic returns similar to traditional shrimp culture. Based on these results, we recommend Nile tilapia culture to farmers whose ponds are 20 ppt. This provides a profitable production option for farmers in areas subject to low salinities, or during the rainy season when salinities are depressed. Because outbreaks of white-spot disease are particularly common and severe during the rainy season, Nile tilapia culture provides a viable option for income generation for Acehnese tambak farmers under conditions where shrimp culture is too risk
PENENTUAN KATEGORI KONSENTRASI BERBAGAI PEUBAH KIMIA KUALITAS TANAH PADA KEDALAMAN BERBEDA DI TAMBAK PROVINSI SULAWESI SELATAN, INDONESIA
Kualitas tanah adalah salah satu faktor penentu keberhasilan dan keberlanjutan usaha budidaya tambak, termasuk budidaya tambak di Provinsi Sulawesi Selatan, Indonesia. Namun demikian, sampai saat ini belum ada data mengenai kategori konsentrasi peubah kimia kualitas tanah untuk tanah tambak di Indonesia. Studi ini bertujuan untuk menentukan kategori konsentrasi peubah kimia kualitas tanah sebagai langkah awal dalam menginterpretasi kualitas tanah tambak di Sulawesi Selatan secara khusus dan di Indonesia secara umum. Contoh tanah diambil pada 1.196 titik pengambilan dengan masing-masing dua kedalaman tanah yang tersebar di 13 kabupaten di Sulawesi Selatan. Sebanyak 18 peubah kimia kualitas tanah telah diukur langsung di lapangan atau dianalisis di laboratorium. Uji t digunakan untuk mengetahui perbedaan kualitas tanah pada kedalaman yang berbeda. Konsentrasi setiap peubah kimia kualitas tanah disusun dari terkecil ke terbesar kemudian dilakukan penentuan letak desil dan nilai desil sebagai dasar dalam penentuan kategori konsentrasi setiap peubah kimia kualitas tanah. Hasil studi menunjukkan bahwa secara umum tanah tambak di Sulawesi Selatan pada kedalaman 0-0,2 m memiliki kemasaman dan unsur toksin (Fe, Al) yang lebih rendah dan sebaliknya konsentrasi unsur hara makro (N, P) yang lebih tinggi dibandingkan pada kedalaman 0,2-0,5 m. Peubah kualitas tanah lainnya seperti SKCl, SP,, dan SPOS relatif sama pada kedua kedalaman. Data setiap peubah kualitas tanah telah disusun ke dalam kategori konsentrasi (sangat rendah, rendah, sedang, tinggi, sangat tinggi) untuk memfasilitasi perbandingan dengan data lain mengenai kualitastanah untuk budidaya tambak. Hasil studi ini tidak disarankan untuk digunakan dalam menentukan hubungan antara kualitas tanah dan produktivitas tambak, tetapi dapat menjadi dasar dalam menentukan peubah kimia kualitas tanah tambak termasuk kategori sangat rendah, rendah, sedang, tinggi, atau sangat tinggidan membuat keputusan untuk perbaikan kualitas tanah
Granulocyte-colony stimulating factor does not prevent in vitro cisplatin-induced germ cell reduction in immature human and mouse testis
How a Diverse Research Ecosystem Has Generated New Rehabilitation Technologies: Review of NIDILRR’s Rehabilitation Engineering Research Centers
Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a “total approach to rehabilitation”, combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970’s, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program
The state of the Martian climate
60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
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