Tài liệu miễn phí Sinh học

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Cách tổ chức hoạt động trải nghiệm các chủ đề sinh học trong môn Khoa học tự nhiên tiếp cận chương trình giáo dục phổ thông mới ở bậc trung học cơ sở

Bài viết này giới thiệu về khái niệm hoạt động trải nghiệm, cách tổ chức hoạt động trải nghiệm và mối quan hệ giữa hoạt động trải nghiệm gắn với sự phát triển năng lực sáng tạo. Trên cơ cơ đó lấy ví dụ minh họa cho việc tổ chức hoạt động trải nghiệm trong dạy học chủ đề “Tìm hiểu sinh vật ngoài thiên nhiên”, Khoa học tự nhiên 6 - Chương trình giáo dục phổ thông mới.

5/21/2021 8:12:22 PM +00:00

Tối ưu hóa điều kiện trích ly thu nhận triterpensaponin từ rau đắng biển (Bacopa monnieri (L.) Wettst) bằng enzyme cellulase

Rau đắng biển (Bacopa monnieri (L.) Wettst) còn gọi là rau sam đắng, phân bố rộng ở các vùng nhiệt đới và cận nhiệt đới. Trong nghiên cứu này nhóm nghiên cứu sử dụng enzyme cellulase để hỗ trợ trích ly, khai thác hợp chất triterpensaponin từ rau đắng biển. Các yếu tố nghiên cứu sàng lọc bao gồm tỷ lệ nguyên liệu: Dung môi; pH; nhiệt độ; thời gian trích ly và nồng độ enzyme sử dụng.

5/21/2021 8:04:08 PM +00:00

Khảo sát ảnh hưởng của độ cồn và lượng đường bổ sung đến quá trình lên men giấm vang từ xơ mít (Artocarpus heterophyllus)

Mục tiêu chính của nghiên cứu này là khảo sát quá trình lên men giấm từ vải vụn của mít. Quá trình lên men giấm được thực hiện ở nồng độ cồn 4,0-10,0% được sản xuất từ vải vụn của mít cung cấp hàm lượng sucrose 25-75 g/L.

5/21/2021 3:14:38 PM +00:00

Biểu hiện gen chống oxy hóa trên cây phát tài (Dracaena sanderiana) trong điều kiện nhiễm độc chì

Nội dung nghiên cứu của bài viết này là tìm hiểu biểu hiện gen chống oxy hóa của cây phát tài trong điều kiện nhiễm độc chì, làm cơ sở cho các nghiên cứu tiếp theo như can thiệp vào sự biểu hiện gen nhằm tìm hiểu, cải thiện và tăng khả năng ứng dụng các loài thực vật trong xử lý ô nhiễm chì.

5/21/2021 3:14:25 PM +00:00

Phân tích trình tự DNA Barcode của một số mẫu đinh lăng được thu thập tại Việt Nam

Bài viết tiến hành phân tích mã vạch DNA của 18 mẫu giống đinh lăng được thu thập ở Việt Nam để nhận diện và phân loại các nhóm giống đinh lăng.

5/21/2021 3:14:02 PM +00:00

Cultural and physiological requirements of Colletotrichum gloeosporioides causing anthracnose of mango

Mango is regarded as „king of fruits‟ and is grown mainly in tropical and subtropical regions of the world. Anthracnose is one of the devastating disease, known to cause yield loss from 10 to 80 per cent in orchard and also being post-harvest disease, it cause an economical loss to the tune of 15-20 per cent. The disease is caused by the fungal pathogen Colletotrichum gloeosprorioides.

5/21/2021 3:00:58 PM +00:00

A preliminary study on diversity and community structure of phytoseiid mites associated with medicinal plants in selected locations of Telangana

In the present study, an investigation was carried out to explore the diversity and community structures of phytoseiid mite fauna associated with medicinal plants in four selected locations viz. Ananthagiri, CSIRCIMAP campus, Kotapally and Eturangaram sanctuary situated in Southern, Northern and Central agroclimatic zones of Telangana.

5/21/2021 2:58:19 PM +00:00

Isolation and partial characterisation of streptococcus suis bacteriophage

Therefore, it is necessary to investigate and determine the biological characteristics of phages for practical therapeutic applications and to expand our understanding of phages as alternatives to antibiotics. With the goal of improving treatment and prevention of S. suis infection, we isolated, characterized lytic phage against S. suis strains

5/21/2021 2:57:16 PM +00:00

Isolation, screening, optimization of cultural conditions of submerged fermentation and partial purification of alkaline chitinase enzyme from Fusarium sp.

Isolation, screening, optimization of cultural conditions of submerged fermentation and partial purification of alkaline chitinase enzyme from Fusarium sp.

5/21/2021 2:54:53 PM +00:00

Isolation and partial characterization of bacteriophage against Salmonella gallinarum

A lytic bacteriophage (SGP-1) against Salmonella gallinarum (S. gallinarum) was isolated by an enrichment protocol from the sewage water of a poultry farm. The presence of bacteriophage was observed by spot test over the bacterial lawn and double agar overlay assay. Isolated phage was able to produce clear, circular plaques of 2-3mm diameter on S. gallinarum lawn culture.

5/21/2021 2:49:03 PM +00:00

Invitro investigation of potassium silicate on mycelial growth of Fusarium isolate

Mango malformation (MM) is an ambiguous mango disease with tremendous economic importance throughout the mango growing regions. Several studies reported that Fusarium species especially Fusarium mangiferae is associated with mango malformation. Silicon is an essential element, which plays a vital role in plant microbial interaction. It deposits under the cuticle and acts as a physical barrier that protects the plant from fungal infection. The present study was conducted to observe the in-vitro application of various silicon (potassium silicate) concentrations on mycelial growth of Fusarium isolates.

5/21/2021 2:47:37 PM +00:00

Molecular characterization of germplasm accessions of G. hirsutum using SSR markers

The present investigation studied genetic diversity of ninety four cotton germplasm accessions, in order to improve genetic base of the present cultivars. Out of 48 primer pairs surveyed, 20 (42%) were showing polymorphism. The average number of alleles per locus was 2.45.

5/21/2021 2:45:48 PM +00:00

Effects of different thawing methods on the ph, water holding capacity, extract release volume and TBA value of broiler chicken under repeated freeze-thaw cycles

The present study was undertaken to assess broiler chicken breast fillets' physicochemical quality characteristics changes caused due to repeated freeze-thaw cycles by three different thawing methods. Meat samples were subjected to slow freezing at -18℃ for seven days and thawed under various thawing methods viz.

5/21/2021 2:44:52 PM +00:00

Study on seasonal fluctuation of physicochemical properties of water and fish diversity towards future management of a natural water bodies Rajar beel wetland, North 24 Parganas, West Bengal, India

The present study was made to find out the health status of a wetland Rajar Beel, North 24 Parganas, West Bengal, India in relation to physicochemical properties of water. This wetland is rich in aquatic biodiversity. The study focused on the seasonal fluctuation of physicochemical parameters of water and diversity of fish fauna during pre-monsoon, monsoon and post-monsoon during March 2019 to February 2020.

5/21/2021 2:40:35 PM +00:00

Immobilization optimization and characterization of immobilized lipase from Lysinibacillus macroides FS1 for biodiesel production

This study therefore focused on optimization of lipase immobilization of Lysinibacillus macroides FS1 and characterise the immobilized lipases to investigate the potential application in biodiesel production.

5/21/2021 2:39:14 PM +00:00

Effect of supplementation on the properties of yogurt: A review

In this review, the effects of milk fortification with various food components on physicochemical as well on sensorial properties of yogurt products are studied and described. The fortification described under the types of food components like carbohydrates, proteins, dietary fibres, minerals and vitamins.

5/21/2021 2:38:05 PM +00:00

Biodegradation of textile dye reactive black GDN by free cells isolated from soil and textile effluents

The present study deals with the degradation of Reactive black GDN by different bacterial cultures isolated from a contaminated site. Amongst 5 cultures, the isolate 4 displayed 96% decolourisation of Reactive black GDN (100 mgl-1 ) in 24h to 72 h. The colour removal efficiency of the isolate was further improved by optimizing various parameters. The decolourisation of the dye was 1.9 times higher under static as compared to shaking condition. The pH 7.0 and 37oC temperature were found to be optimum for the decolourisation of the dye. The isolate was able to decolorize the dye in the range of 50-500 mg l-1 .

5/21/2021 2:37:10 PM +00:00

Capabilities of pure culture of bacteria in the biodegradation of polycyclic aromatic hydrocarbons and total petroleum hydrocarbons in oilfield wastewater

This study therefore compares the potentials of individual isolates in the biodegradation of polycyclic aromatic hydrocarbons and total petroleum hydrocarbon in an oilfield wastewater.

5/21/2021 2:36:48 PM +00:00

A review on effect of amylose/amylopectin, lipid and relative humidity on starch based biodegradable films

This paper reviewed for starch as natural polymer, chemical form of starch for conversion in plastic film, effect of amylose/amylopectin content, effect of lipid content and effect of relative humidity on properties of starch film. For strengthening of plastic film from starch, a blend with synthetic polymer is also discussed with limited synthetic polymers like polyethylene, polyester, polypropylene, and polylactic acid considering the length of review article.

5/21/2021 2:36:16 PM +00:00

Fecal sludge management technologies: Comparing the opportunities and challenges

The review of several FS management technologies has ultimately aided in developing an affirmative understanding that geotextile-based technologies have genuinely an upper hand within limited capacities, while mechanization is a mandate for large-scale centralized management.

5/21/2021 2:34:03 PM +00:00

SARS-CoV-2 triggers inflammatory and cell death in experimental infection by activating human cells caspases

Apoptosis is a process that occurs in programmed physiological and nonphysiological cell death. In morphological aspect, among apoptosis products, cell shrinkage, subsequent to the degeneration of the nucleus characterized by condensation of chromatin, followed by the nuclear membrane disappearance. In particular, apoptosis modulation in SARS-CoV infection seems to be directly associated with specific cell-type interactions, which can significantly influence the manifestations resulting from the pathology. Therefore, it is noted the need for studies that promote debates about the modulation of apoptosis in animals and humans, infected by SARS-CoV.

5/21/2021 2:33:57 PM +00:00

Diversity of mosquito fauna in different habitats of district Dehradun, Uttarakhand

In the present study a total of 2822 specimens of 25 species of mosquitoes belonging to 6 genera viz., Anopheles, Culex, Aedes, Armigeres, Toxorhynchites and Uranotaenia from distt Dehradun between January 2019 to December 2020 were recovered.

5/21/2021 2:33:42 PM +00:00

Isolation of antibiotic producing actinomycetes from saltpans

The present investigation was undertaken to isolate, characterize and screen the actinomycetes from salt pan sediment soils.

5/21/2021 2:33:28 PM +00:00

The enormous world of diverse molecular markers

The creation and use of molecular markers for the recognition and exploitation of DNA polymorphism is one of the most important developments in the field of molecular biology. Molecular markers, due to their consistency, low cost and effortless use have become a popular tool for a variety of applications including gene tagging, phylogenetic and genetic diversity analysis and genome mapping.

5/21/2021 2:31:22 PM +00:00

Effects of three organic amendments on polycyclic aromatic hydrocarbon degradation from crude oil polluted artisanal refining site

The aim of this study is to evaluate the effectiveness of three different organic amendments in the biodegradation of PAHs against natural attenuation technique.

5/21/2021 8:19:17 AM +00:00

A study on development of instant kodo dosa mix and evaluation of its nutritional composition and shelf life

Value added healthy instant foods are the requirements of modern society and also are becoming popular day by day. These foods are convenient to use and time saving. Dosa is a popular vegetarian fermented South Indian breakfast food item made from parboiled rice, black gram dhal, fenugreek seeds, edible oil and salt. In the present study the attempts were made to standardize instant kodo millet dosa mix by incorporation of kodo millet flours with parboiled rice at different incorporation levels at 25%, 50%, 75%, 100% and control 100% with rice flour.

5/21/2021 8:15:50 AM +00:00

Insecticide resistant natural enemies and their role in IPM

Knowledge of the natural and potential variation in the tolerance of natural enemies to pesticides may improve the design of robust IPM strategies by extending the role of biological control in some agricultural systems and by increasing the number of available compounds to control diseases and key, secondary, and invasive pests. There are a number of excellent revisions on pesticide resistance in natural enemies. In the present review, new cases of insecticide resistance in natural enemies are discussed, as a better understanding of pesticide resistance in natural enemies will allow us to enhance the integration of chemical and biological tools in IPM programs this time period.

5/21/2021 8:11:09 AM +00:00

The fauna and ecological groups of bivalve mollusks of Kamashi and Karabakh reservoirs

There are 9 species and 1 subspecies in the reservoirs of the Kashkadarya coast in Karabakh and 6 species and 1 subspecies in Kamashi. In the Kamashi reservoir, peloreophiles make up 57%, rheophiles 14% and crenophiles 29%. In the Karabakh reservoir, peloreophiles were found to be 70%, rheophiles 10%, pelolimnophiles 10% and crenophiles 10%.

5/21/2021 8:00:29 AM +00:00

Bioremediation of textile and tannery effluents – An overview

Water is considered to be one of the essential resources for the survival of living beings. The vital resource is exposed to toxic pollutant due to the untreated industrial discharge from tannery, textile and other industries. Effluents discharged from the tannery and textile industries contains an ample of heavy metals and other toxic azo dyes which affects the living beings including aquatic and terrestrial flora and fauna. The removal of this toxic compounds from the water bodies has become a challenge to the human society. Various treatments are used for the removal of these toxic compounds but due to its undesirable features such as partial removal, higher maintenance cost these methods are considered as ineffective process.

5/21/2021 7:58:21 AM +00:00

Biodegradation and detoxification of congo red by intuitive bacterial strain TVU-CR4

In the present study, effluent samples were collected from various textile and dyeing industries located in and around Vellore District, Tamilnadu, India and were exploited for the screening and isolation of bacterial strains that were capable of decolorizing Congo red. Optimization of cultural conditions was carried out to maximize decolorization efficiency of the bacterial isolate TVU-CR4 towards Congo red.

5/21/2021 7:58:15 AM +00:00