Attacks On Near Field Communication Devices

For some years, Near Field Communication (NFC) has been a popularly known technology characterized by its short-distance wireless communication, mainly used in providing different agreeable services such as payment with mobile phones in stores, Electronic Identification, Transportation Electronic Ticketing, Patient Monitoring, and Healthcare. The ability to quickly connect devices offers a level of secure communication. That notwithstanding, looking deeply at NFC and its security level, identifying threats leading to attacks that can alter the user’s confidentiality and data privacy becomes obvious. This paper summarizes some of these attacks, emphasizing four main attack vectors, bringing out a taxonomy of these attack vectors on NFC, and presenting security issues alongside privacy threats within the application environment

Clonal variations in seed characters and germination in Hevea brasiliensis

The principal form of dissemination for most plant species is seeds, an important source of biodiversity conservation. For rubber plantations, seeds are the initial material for seedling production. In Cameroon, there is limited information related to clonal seed characterisation and early growth performance. This study sorts to characterise Hevea brasiliensis seeds from GT 1, PR 107, PB 217, PB 235, and PB 260 clones and evaluate the germination rate and seedling early growth characteristics to enable planning for nursery management. Clone GT 1 had the highest seed length (3.98 cm), seed kernel weight (3.4 g) and total seed weight (4.75 g). Clone PB 235 had the heaviest shell (1.96 g). There was no significant correlation between seed size, germination percentage and early seedling growth for the different clones. Clone PR 107 had the lowest per cent seed germination, with just 55 per cent of its seed germinating after two weeks, whereas clone PB 217 had the highest seed germination (92.5%). Seedling height, seed germination percentage and shell weight were significantly correlated. The results of this study provide some useful information for rubber nursery managers

Investigations on the nutritional status of Hevea brasiliensis plantations in the humid forest zone of CameroonPart 2: Establishment of macro nutrient norms

Zur Bewertung optimaler Nährstoffkonzentrationen für bessere und nachhaltige Erträge werden Nährstoffstandards benötigt. Ziel dieser Arbeit war die Ableitung von optimalen Nährstoffkonzentrationen in Böden und Pflanzen für Hevea brasiliensis in der Feuchtwaldzone von Kamerun. Zwischen August 2010 und August 2011 wurde eine Bestandsaufnahme der Nährstoffgehalte in mehreren Gummibaum-Anbaugebieten Kameruns durchgeführt. Boden- und Pflanzenproben wurden zwecks Untersuchung der Makronährstoffgehalte gesammelt. Unter Verwendung der Makronährstoffkonzentrationen und Erträge wurden „boundary lines“ kalkuliert und mittels polynomischer Funktionen 2. Ordnung beschrieben. Durch Gleichsetzung der ersten Ableitung der errechneten Gleichungen mit null wurden folgende optimal Blatt-Nährstoffgehalte für Hevea brasiliensis ermittelt: 3,5% N, 0,31% P, 1,53% K, 0,28% Mg und 0,83% Ca. Für Böden ergaben sich optimale Gehalte von 3,1% organisches C, 0,18% N, 5,9 mg/kg P, 262 mg/kg K, 432 mg/kg Ca und 16 mg/kg Mg. Diese Gehalte wurden errechnet, inem die „boundary line“-Gleichung bei 95% des optimalen Er­trages gelöst wurde. Die ermittelten Optimalgehalte für Hevea brasiliensis unterschieden sich größtenteils deutlich von jenen, die Studien in anderen Regionen ergeben hatten. Dies zeigt, dass für eine effective Nährstoffdiagnose lokal ermittelte Richtlinien verwendet werden sollten. Die hier ermittelten Richtlinien werden zukünftig zur Bewertung des Nährstoffstatus von Hevea brasiliensis-Plantagen in Kamerun verwendet.    Standard nutrient values are needed for the assessment of optimum nutrient concentrations for improved and sustained yields. The aim of this study was to establish optimum soil and plant nutrient values for Hevea brasiliensis in the humid forest region of Cameroon. A nutrient survey was carried out during August 2010 and August 2011 in some rubber growing zones of Cameroon. Both soil and leaf samples were collected for the determination of their macronutrient contents. Using the macro­nutrient concentrations and yield data, boundary lines were calculated. These boundary lines were described by second degree polynomials. Equating the first derivative of the second degree polynomial equations to zero, the following optimum nutrient values 3.5%, 0.31%, 1.53%, 0.28% and 0.83% were obtained for N, P, K, Mg and Ca, respectively, for Hevea leaves. On the other hand, the optimum soil nutrient levels were 3.1% for organic carbon, 0.18% for N, 5.9 mg/kg for P, 262. mg/kg for K, 432 mg/kg for Ca and 16 mg/kg for soil Mg. The optimum soil and plant nutrient ranges were obtained by solving the boundary line equation at 95% of the optimum yield. The optimum nutrient values for Hevea brasiliensis obtained in this study were to a large extent different from those obtained in studies elsewhere. This is an indication that for effective nutrient diagnosis, locally derived norms should be used. Those local nutrient norms will be used for nutrient assessment in Hevea plantations in Cameroon.   &nbsp

Investigations on the nutritional status of Hevea brasiliensis plantations in the humid forest zone of CameroonPart 1: Micronutrient status and distribution in soils

Mikronährstoffe sind essentiell für das Wachstum von Pflanzen. Um Aussagen über die optimale Mikronährstoffversorgung von Hevea brasiliensis treffen zu können, wurden Mikronährstoffkonzentrationen ausgewählter Böden in Kamerun unter Hevea brasiliensis-Plantagen untersucht. Insgesamt wurden 130 Bodenproben auf ihre AAAc-EDTA-extrahierbaren Mikronährstoffkonzen­trationen, sowie pH-Wert und organische C-Gehalte hin analysiert. 62% der beprobten Standorte wiesen Mängel an extrahierbarem Zn auf, 15% an extrahierbarem Fe und 10% an extrahierbarem Cu. Dies zeigt, dass ein Hauptaugenmerk auf eine ausreichende Zn-Versorgung gerichtet werden sollte. AAAc-EDTA-extrahierbare Konzentrationen an Mn, Fe, Cu und Zn in den Böden variierten zwischen 0,3-128, 14-235, 0,49-24 und 0,3-12 mg/kg. Bezogen auf die mittleren Gehalte war die Reihenfolge der Konzentrationen wie folgt: Fe > Mn > Cu > Zn. Die Korrelationsanalyse zeigte, dass die AAAc-EDTA-extrahierbaren Cu- und Fe-Gehalte signifikant positiv mit den Gehalten an organischem C korrelierten. Darüber hinaus war eine positive Korre­lation der AAAc-EDTA-extrahierbaren Cu-, Mn- und Zn-Gehalte mit dem Boden-pH sowie zwischen Zn, Cu und Fe zu beobachten.    Micronutrients are very essential for plant growth. To make statements about the optimum micronutrient supply for Hevea brasiliensis, the micronutrient concentrations of selected soils in Cameroon under Hevea brasiliensis cultivation were studied. A total of 130 soil samples from plantations were collected and analyzed for their AAAc-EDTA-extractable micronutrient concentrations, pH and soil organic carbon. 62% of the sampled sites were deficient in extractable Zn, 15% in extractable Fe and 10% in extractable Cu. This shows that one main focus should be on a sufficient Zn-nutrition. AAAC-EDTA-extractable concentrations of Mn, Fe, Cu and Zn in the soils varied from 0.3 to 128, 14 to 235, 0.49 to 24 and from 0.3 to 12 mg/kg. Considering their mean values, the order of abundance of the micronutrients was Fe > Mn > Cu > Zn. Simple correlation analysis revealed that the AAAc-EDTA-extractable Cu- and Fe-amounts are significantly and positively correlated with soil organic carbon. There also was a positive correlation between AAAc-EDTA-extractable Cu, Mn and Zn with the pH-value of the soil and between Zn and Cu and Fe.   &nbsp