Apatite as an interesting seed to remove phosphorus from wastewater in constructed wetlands

2005 ◽  
Vol 51 (9) ◽  
pp. 193-203 ◽  
Author(s):  
P. Molle ◽  
A. Liénard ◽  
A. Grasmick ◽  
A. Iwema ◽  
A. Kabbabi
Keyword(s):  
Constructed Wetlands ◽  
Surface Waters ◽  
Ionic Composition ◽  
Calcium Content ◽  
Phosphorus Retention ◽  
Negative Effects ◽  
Long Term Retention ◽  
Sorption Mechanisms ◽  
Parallel Observation

Intensive use of phosphates has resulted in high P levels in surface waters and therefore eutrophication problems. Over the last decade many studies have revealed the advantage of using specific materials with efficient phosphorus retention capacities. Recent studies state that Ca materials are of particular interest for long-term retention of P, but can induce negative effects. To improve P retention and avoid negative counter-effects we tested the potential of natural apatites. Apatite sorption was evaluated using batch and open reactor experiments. Batch experiments identify sorption mechanisms and the influence of the ionic characteristics of the solution; open reactor experiments evaluate sorption capacities in relation to the ionic composition of the solution and biomass development. In parallel, observation of the material by electron microscopy was used to give more precision information about the mechanisms involved. This work reveals the strong chemical affinity between apatites and phosphorus. Compared to other calcareous materials apatite is better able to maintain low outlet P levels. After more than 550 days feeding, sorption was still present and low P outlet levels were still being obtained when sufficient contact time and calcium content in the solution were ensured. This work demonstrates the advantages of using apatites for phosphorus removal in constructed wetlands. The behaviour of apatite in phosphorus retention is explained and its suitability for use in such extensive systems defined.

scholarly journals Contrasting Traditional In-Class Exams with Frequent Online Testing

2015 ◽  
Vol 4 (2) ◽  
pp. 30-40 ◽  
Author(s):  
Mary L Still ◽  
Jeremiah D Still
Keyword(s):  
Student Learning ◽  
Student Learning Outcomes ◽  
Online Testing ◽  
Negative Effects ◽  
Reported Study ◽  
Online Assessments ◽  
Long Term Retention ◽  
Testing Condition ◽  
Subjective Outcomes

Although there are clear practical benefits to using online exams compared to in-class exams (e.g., reduced cost, increased scalability, flexible scheduling), the results of previous studies provide mixed evidence for the effectiveness of online testing. This uncertainty may discourage instructors from using online testing. To further investigate the effectiveness of online exams in a naturalistic situation, we compared student learning outcomes associated with traditional in-class exams compared to frequent online exams. Online exams were administered more frequently in an attempt to mitigate potential negative effects associated with open-book testing. All students completed in-class and online exams with order of testing condition (in-class first, or online first) counterbalanced between students. We found no difference in long-term retention for material that had originally been tested using frequent online or traditional in-class exams and no difference in self-reported study time. Overall, our results suggest that frequent online assessments do not harm student learning in comparison to traditional in-class exams and may impart positive subjective outcomes for students. 

Long-term retention is greater following closed-book tests than open-book tests

2006 ◽  
Author(s):  
Pooja K. Agarwal ◽  
Jeffrey D. Karpicke ◽  
Sean H. Kang ◽  
Henry L. Roediger ◽  
Kathleen B. McDermott
Keyword(s):  
Open Book ◽  
Term Retention ◽  
Long Term Retention

Influence of NPK fertilization on weed flora in maize field

2014 ◽  
Vol 63 (1) ◽  
pp. 139-148 ◽  
Author(s):  
Éva Lehoczky ◽  
M. Kamuti ◽  
N. Mazsu ◽  
J. Tamás ◽  
D. Sáringer-Kenyeres ◽  
...  
Keyword(s):  
Plant Nutrition ◽  
Crop Production ◽  
N Availability ◽  
Weed Species ◽  
Negative Effects ◽  
Production Factors ◽  
Maize Field ◽  
Weed Flora ◽  
Npk Fertilization

Plant nutrition is one of the most important intensification factors of crop production. The utilization of nutrients, however, may be modified by a number of production factors, including weed presence. Thus, the knowledge of occurring weed species, their abundance, nutrient and water uptake is extremely important to establish an appropriate basis for the evaluation of their risks or negative effects on crops. That is why investigations were carried out in a long-term fertilization experiment on the influence of different nutrient supplies (Ø, PK, NK, NPK) on weed flora in maize field.The weed surveys recorded similar diversity on the experimental area: the species of A. artemisiifolia, S. halepense and D. stramonium were dominant, but C. album and C. hybridum were also common. These species and H. annuus were the most abundant weeds.Based on the totalized and average data of all treatments, density followed the same tendency in the experimental years. It was the highest in the PK treated and untreated plots, and significantly exceeded the values of NK fertilized areas. Presumably the better N availability promoted the development of nitrophilic weeds, while the mortality of other small species increased.Winter wheat and maize forecrops had no visible influence on the diversity and the intensity of weediness. On the contrary, there were consistent differences in the density of certain weed species in accordance to the applied nutrients. A. artemisiifolia was present in the largest number in the untreated control and PK fertilized plots. The density of S. halepense and H. annuus was also significantly higher in the control areas. The number of their individuals was smaller in those plots where N containing fertilizers were used. Contrary to them, the density of D. stramonium, C. album and C. hybridum was the highest in the NPK treatments.

The foundations of peaceful coexistence after the war ... Mosul is a model

2019 ◽  
pp. 178
Author(s):  
Omar Hashim Thanon
Keyword(s):  
Ethnic Diversity ◽  
Psychological Consequences ◽  
Peaceful Coexistence ◽  
Negative Effects ◽  
Mass Displacement ◽  
The Common ◽  
Near Term ◽  
Post War ◽  
Common Destiny

Since peaceful coexistence reflects in its various aspects the concept of harmony between the members of the same society with their different national, religious and sectarian affiliations, as well as their attitudes and ideas, what brings together these are the common bonds such as land, interests and common destiny. But this coexistence is exposing for crises and instability and the theft of rights and other that destroy the communities with their different religious, national, sectarian, ethnic aspects, especially if these led to a crisis of fighting or war, which produces only destruction and mass displacement, ttherefore, the process of bridging the gap between the different parts of society in the post-war phase through a set of requirements that serve as the basis for the promotion of peaceful coexistence within the same country to consolidate civil and community peace in order to create a general framework and a coherent basis to reconstruct the community again.      Hence the premise of the research by asking about the extent of the possibility and ability of the community of religious and ethnic diversity, which has been exposed to these crises, which aimed at this diversity, basically to be able to rise and re-integrate within the same country and thus achieve civil and community peace, and Mosul is an example for that, the negative effects of the war and the accomplices of many criminal acts have given rise to hatred and fear for all, leading to the loss of livelihoods, which in the long term may have devastating social and psychological consequences.        To clarify all of this, the title of the first topic was a review of the concept and origin of peaceful coexistence. While the second topic dealt with the requirements of peaceful coexistence and social integration in Mosul, the last topic has identified the most important challenges facing the processes of coexistence and integration in Mosul. All this in order to paint a better future for the conductor at all levels in the near term at the very least to achieve the values of this peaceful coexistence, especially in the post-war period.

Effects of GMO agricultural products on living things

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
ERCAN ÇATAK ◽  
Ali ATALAY
Keyword(s):  
Genetically Modified Organisms ◽  
World Population ◽  
Negative Effects ◽  
Qualitative And Quantitative ◽  
Living Things ◽  
Late Twentieth ◽  
Agricultural Use ◽  
Late Twentieth Century ◽  
Living Creature

By obtaining changes on gene sequences of living things with the applied biotechnological methods; The idea of "Genetically Modified Organisms (GMO)", which aims to bring the living creature in question the original gene combinations with the desired characteristics, came to life in the late twentieth century. Despite the high probability that hunger problems may increase with the increasing world population; It is thought that plant breeding with classical farming methods will be insufficient in solving these problems. With various GMO applications developed all over the world, it aims to produce solutions to these problems. With the presence of GMO, it was possible to increase the shelf life of qualitative and quantitative values of the existing foods. In addition, decreases in agricultural use of pesticides used in agricultural struggle and threatening human health with GMO production are noteworthy. However, some concerns about anomalies that may occur in living things fed GMO products remain on the agenda. Because, in the long term, there is no clear and precise information that GMO will not have negative effects on living things; There are many recorded incidents showing their negative effects.

Functional correlates of negative effects of allostatic load with long-term adaptation to labor factors

2020 ◽  
pp. 682-682
Author(s):  
T. D. Lipenetskaia
Keyword(s):  
Allostatic Load ◽  
External Exposure ◽  
Negative Effects

Under certain conditions of strong or prolonged external exposure, signs of either allostatic load or allostatic load are formed. The question of the different physiological nature of these states is discussed.

Retrieval practice promotes long-term retention irrespective of the placement

2020 ◽  
Author(s):  
alice latimier ◽  
Arnaud Rierget ◽  
Son Thierry Ly ◽  
Franck Ramus
Keyword(s):  
Retention Interval ◽  
Retrieval Practice ◽  
Memory Retention ◽  
Term Retention ◽  
Long Term Retention

The current study aimed at comparing the effect of three placements of the re-exposure episodes on memory retention (interpolated-small, interpolated-medium, postponed), depending on whether retrieval practice or re-reading was used, and on retention interval (one week vs one month).

Negative Media Effects and Islamic Remedies (Penyelesaian Kepada Kesan Negatif Media Menurut Perspektif Islam)

2010 ◽  
Vol 7 (2) ◽  
pp. 215
Author(s):  
Mohd. Shuhaimi Ishak
Keyword(s):  
Public Relations ◽  
Social Influences ◽  
The Political ◽  
Negative Effects ◽  
Essential Form ◽  
The Media ◽  
The Government ◽  
Effects Of Media ◽  
Political Economic

 Abstract Generally speaking, media is extensively used as the means to disseminate news and information pertaining to business, social, political and religious concerns. A portion of the time and space of media has now become an important device to generate economic and social activities that include advertising, marketing, recreation and entertainment. The Government regards them as an essential form of relaying news and information to its citizens and at the same time utilizes them as a powerful public relations’ mechanism. The effects of media are many and diverse, which can either be short or long term depending on the news and information. The effects of media can be found on various fronts, ranging from the political, economic and social, to even religious spheres. Some of the negative effects arising from the media are cultural and social influences, crimes and violence, sexual obscenities and pornography as well as liberalistic and extreme ideologies. This paper sheds light on these issues and draws principles from Islam to overcome them. Islam as revealed to humanity contains the necessary guidelines to nurture and mould the personality of individuals and shape them into good servants. Key Words: Media, Negative Effects, Means, Islam and Principles. Abstrak Secara umum, media secara meluas digunakan sebagai sarana untuk menyebarkan berita dan maklumat yang berkaitan dengan perniagaan, kemasyarakatan, pertimbangan politik dan agama. Sebahagian dari ruang dan masa media kini telah menjadi peranti penting untuk menghasilkan kegiatan ekonomi dan sosial yang meliputi pengiklanan, pemasaran, rekreasi dan hiburan. Kerajaan menganggap sarana-sarana ini sebagai wadah penting untuk menyampaikan berita dan maklumat kepada warganya dan pada masa yang sama juga menggunakannya sebagai mekanisme perhubungan awam yang berpengaruh. Pengaruh media sangat banyak dan pelbagai, samada berbentuk jangka pendek atau panjang bergantung kepada berita dan maklumat yang brekenaan. Kesan dari media boleh didapati mempengaruhi pelbagai aspek, bermula dari bidang politik, ekonomi, sosial bahkan juga agama. Beberapa kesan negatif yang timbul dari media ialah pengaruhnya terhadap budaya dan sosial, jenayah dan keganasan, kelucahan seksual dan pornografi serta ideologi yang liberal dan ekstrim. Kertas ini menyoroti isu-isu ini dan cuba mengambil prinsip-prinsip dari ajaran Islam untuk mengatasinya. Tujuan Islam itu sendiri diturunkan kepada umat manusia ialah untuk menjadi pedoman yang diperlukan untuk membina dan membentuk keperibadian individu dan menjadikan manusia hamba yang taat kepada Tuhannya. Kata Kunci: Media, Kesan Negatif, Cara-cara, Islam dan Prinsip-prinsip.

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