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Isolation, characterization and enzymatic potentiali ties of fungi isolated from the soil of upper Kodaikanal, Tamil Nadu, India
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This paper reports on the design and engineering analysis of a low-cost coconut peeling machine for small medium-sized enterprise. The aim of the design was to develop a machine that could remove the exterior coconut husk in a hexagonal form. The concept adopted was based on vertical trimmings and the mechanism composed of blades, and holder to clamp the young coconut. By using finite element analysis, the viability of the proposed design for the coconut peeler machine and its mechanical systems were examined. The effect of loading and the rupture force on the holders were also analysed. In addition, the cost estimation was calculated and compared with the market price. Finally, the optimized body frame was examined and optimization was done to minimize the weight of the overall structure without compromising on cost and quality.
In this work, the design and optimisation of an upright assembly for a passenger vehicle were investigated by performing static analysis. Upright assembly is a critical mounting part of a suspension system because it connects all suspension, steering and braking components together to the chassis. Reduction in weight of this component translates to improved performance. The objective of this research was to optimise the upright to reduce the component’s unsprung mass. Solidwork was used to create the model and the static analysis was then performed using the Ansys software, with mild steel as the initial material and the constraints as well as loads were calculated for various scenarios such as braking and cornering maneuvers. The design was optimized by topology optimisation method which considered the areas with low induced stress for material removal. The geometry was then redesigned based on the resulting topology and static analysis was repeated with using different aluminium alloys. The weight of the component was successfully reduced by 50% after the topology optimisation. The use of aluminium, which has a low material density than mild steel, allowed a further weight reduction of 30%. It was also revealed that in comparison to mild steel, the strength was retained with a 15% increase in factor of safety when using aluminium 7075-T6 alloy.
Digital twin is one of the approaches to transform classical and traditional manufacturing to smart manufacturing and Industry Revolution 4.0, which received much attention in the manufacturing domain. Digital twin in manufacturing offers many advantages and solutions include close-loop feedback system, continuous real-time monitoring, or data acquisition through establishing a cyber-physical integration. The low cost and flexibility implementation of Programmable Logic Controller (PLC) enable the technology to become one of the most versatile tools and essential equipment for the automation industry today. However, PLC itself may not be suitable for real-time monitoring and control due to the characteristic of ladder diagram and normally it requires to work with extra devices to achieve the mentioned performance. The main objective of this paper is to develop a Graphic User Interface (GUI) as the cyber entity for real-monitoring and controlling towards the manufacturing process. The interaction between physical sensors, ladder diagram and GUI established cyber-physical integration system and provide engineers a real-time friendly approach to monitor and control the production. The ladder diagram and GUI control system are established by using CX-ONE (CX-Programmer and CX-Designer) together with OMRON PLC CP1L-E model training kits to prototyping the manufacturing cell. The result showed that the GUI allow operator to monitor as well as to control the real-time production.
Undergraduate education in the professional disciplines prioritizes acquisition of discipline-specific knowledge and skills. However, it is worth considering a more holistic approach to shape students into future professionals capable of embracing a keen sense of service to society alongside their professional identity. One way of achieving this is by providing them with opportunities to make meaningful contributions to society directly through their disciplinary education, while enabling them to see the benefits and experience the satisfaction of their involvement. This paper describes the transformative learning experiences of engineering undergraduates in Malaysia who were involved in a service-learning module employing a non-traditional approach. This approach uses their engineering knowledge and skills to directly engage with teenagers from underprivileged communities such as children's homes, orphanages, refugee schools and low-income housing projects. In the beginning many undertook this compulsory module with some reluctance, resigning themselves to it. However, upon completion their views changed, and it was apparent that a profound learning experience had occurred. This paper narrates this experience and uses survey responses and students' reflective journals to convey the outcomes.
p class="Abstract">A proposed method using neuro-fuzzy k-means for the segmentation process of brain has been developed successfully, simulated and assessed. The proposed method has been assessed by using clinical brain images of magnetic resonance imaging (MRI) technology, to segment the three main tissues of the brain. The proposed system is able to segment the three important regions of the brain, which are white matter, grey matter and cerebrospinal fluid (CSF) more accurately, as compared to the benchmarked algorithms. Furthermore, the developed method’s misclassification rate (MR) has been significantly minimized by 88%, 27%, 88%; 82%, 71%, 84%; and 82%, 29%, 83%, as compared to k-means, fuzzy logic, and radial basis function (RBF) for white matter, grey matter and CSF, respectively. Also, from the visual interpretation, it is observed that the brain’s edges are well preserved and the tissues are clearly segmented. From these measures, the proposed integrated approach is shown to be accurate in segmenting the MRI brain tissue with reduced misclassified pixels.</p
In recent times, Additive Manufacturing (AM) has been applied rapidly in almost all fields. This study was conducted to apply the additive manufacturing into an acoustic application by 3D printing the Micro-Perforated Panels (MPP) through Fused Deposition Modelling (FDM) made of Polylactic Acid (PLA) reinforced with wood fibers. MPP were fabricated by altering its perforation volume. Later, the effect of perforation volume on acoustic absorption of the fabricated MPP was measured using the two-microphone impedance tube method as per ISO 10534-2 standard. The result shows altering the perforation volume affects the acoustic absorption of the MPP. MPP with a thickness of 2 mm and a perforation diameter of 0.2 mm shows the maximum sound absorption coefficient of 0.93 at 2173 Hz. It is made possible to absorb the 3D printed MPP made of natural fiber reinforced composite at different spectrums by altering the perforation volume.
The effects of sintering profiles on the Zirconia Toughened Alumina (ZTA) composite containing 0 vol% Y-TZP (pure alumina) to 20 vol% Y-TZP content prepared by a sintering method known as two-stage sintering were investigated. The heating rate was set between 10°C/min to 20°C/min, T 1 set between 1400°C to 1500°C, T 2 at 1350°C and holding time was set at 12 hours. The samples’ microstructural properties and mechanical properties, including bulk density, Vickers hardness, Young’s modulus and fracture toughness, were evaluated. Based on the data obtained, the ZTA composites with 10 vol% Y-TZP sintered at a heating rate of 10°C/min and holding time of 12 hours were able to achieve mechanical properties requirements set by the industry standard. In addition, the maximum ZTA composite’s bulk density was recorded to be above 90% T.D, while the Vickers hardness of the composite was recorded to be exceeding 17 GPa. The ZTA composite also recorded maximum Young’s modulus exceeding 380 GPa and fracture toughness above 6 MPam 1/2 .
Internet of things (IoT) makes it attainable for connecting different various smart objects together with the internet. The evolutionary medical model towards medicine can be boosted by IoT with involving sensors such as environmental sensors inside the internal environment of a small room with a specific purpose of monitoring of person's health with a kind of assistance which can be remotely controlled. RF identification (RFID) technology is smart enough to provide personal healthcare providing part of the IoT physical layer through low-cost sensors. Recently researchers have shown more IoT applications in the health service department using RFID technology which also increases real-time data collection. IoT platform which is used in the following research is Blynk and RFID technology for the user's better health analyses and security purposes by developing a two-level secured platform to store the acquired data in the database using RFID and Steganography. Steganography technique is used to make the user data more secure than ever. There were certain privacy concerns which are resolved using this technique. Smart healthcare medical box is designed using SolidWorks health measuring sensors that have been used in the prototype to analyze real-time data.
This paper presents a design and implementation of an automated smart hydroponics system using internet of things. The challenges to be solved with this system are the increasing food demand in the world, the need of market of new sustainable method of farming using the Internet of Things. The design was implemented using NodeMcu, Node Red, MQTT and sensors that were chosen during component selection based on required parameters and sending it to the cloud to monitor and be processed. Investigation on previous works done and a review of Internet of Things and Hydroponic systems were done. First the prototype was constructed, programmed and tested, as well as sensors data between two different environments were taken and monitored on cloud-based web page with mobile application. Moreover, a bot has been introduced to control the supply chain and for notification purposes. The system improved its performance and allows it to successfully achieve the aim of the entire system implemented. There are some limitations which can be improved as future work such as including data science with the usage of the artificial intelligence to further improve the crops and get better outcome. Lastly to design end user platform to ease user interaction by using attractive design with no technical configuration involved.
This paper gives an optimized modified multiband high gain micro strip antenna which has modified rectangular ring with fork strip which is designed to have 26 GHz for Ka band. The proposed antenna is designed using Rogers RT3003 substrate material with a dielectric constant of 3 and thickness 1.6 mm. Thedesigned antenna is simulated using HFSS and resonated at multi band covering lower band of 26.69 – 26.93 GHz with centre frequency 26.87 GHz; mid band of 29.61 – 32.12 GHz with centre frequency 30.47 GHz and higher band of 34.83 – 36.19 GHz with centre frequency 35.5 GHz, with corresponding bandwidths of 0.24 GHz, 2.5 GHz and 1.36 GHz, respectively. The gain has been improved compared to the existing microstrip patch antenna at 26 GHz.
New optimized 2x2 slotted array antenna is designed using HFSS to operate at 28.1 GHz, using RT6010 substrate with height of 1.6 mm, tangent loss of 0.0023 and dielectric constant of 10.2 and overall dimension of 12x12 mm 2 , for 5G mobile applications. The 2x2 slotted linear array antenna achieved a high gain of 18.3 dB at 28.1 GHz with 10 dB bandwidth of 1.39 GHz, and with 83.21% of size reduction.
The emergence of many internet industries ushers in IOT era, and about to bring us to the point of universal connectivity. In the field of education, the IOT technology has a broad applicable prospect for a more interactive and intelligent way by improving the quality of teaching and management. The proposed class affair management system is mean to enrich the interaction between lecturers and students which in an efficient and smart way. Based on the existing model, a layered architecture is proposed to build the beacon based campus management system. Backend device and protocols compose the physical layer to collect the raw data from physical objects. Data link layer and control layer are responsible for forming required package and sending to corresponding layer. Beacon technology used for proposed design applies Bluetooth low energy 4.0 standard which allowing devices exchange data through Bluetooth at an extremely low power consumption-using a single coin cell battery can last for several years. Saved up to 97 percentage energy compared with similar system. The entire proposed platform allows participants to bring personally owned devices to access campus management system. Through location information, teaching activities and personalized information notification can be automatically accomplished, which will inspire the innovation and development of classroom teaching mode. Beacon technology has a great potential that can be completely transplanted into other scenario such as the hypermarket and library.
Peat samples from Sandynallah basin of the Nilgiris were screened by three methods for the presence of mesophilic and thermophilic filamentous fungi. The samples were collected from a depth of 62 to 244 cm their radiocarbon age ranged from 3730 to >40,000 yr BP. Only 24 fungi, including one thermophilic form, could be isolated from 17 peat samples. The genus Aspergillus was the dominant form.
Microbial population numbers were estimated at two different soil depths in Mawphlang sacred grove forest ofMeghalaya. In general, the number of fungi and bacteria were higher in the surface layer (0-10 em) than in the deep layer of soil (10-20 ern). A total number of 48 and 18 species of fungi were isolated from soil depths of surface and deep layer respectively. Eighteen species of fungi isolated were distributed to all depths. Aspergillus claoaius, A.flavus, A. niger, Cladosporium herb arum, Fusarium moniliforme, Penicillium funiculoeum, Trichoderma harzianum, T. viride and whi te sterile species were the dorninan t fungi in both the soil depths.
The significance of biodiversity to biogeochemical cycling is viewed most directly through the specific biogeochemical transformations that organisms perform. Although functional diversity in soils can be great, it is exceeded to a high degree by the richness of soil species. It is generally inferred from this richness that soil systems have a high level of functional redundancy. As such, indices of species richness probably contribute little to understanding the functioning of soil ecosystems. Another approach stresses the value of identifying “keystone” organisms, that is those that play an exceptionally important role in determining the structure and function of ecosystems. Both views tend to ignore the importance of biodiversity in maintaining the numerous and complex interactions among organisms in soils and their contributions to biogeochemical cycling. We describe some of those interactions and their importance to ecosystem function.
Soil organisms alter the physical, chemical and biological properties of soils in innumerable ways. The composition and structure of biotic communities at one hierarchical level can influence the spatial heterogeneity of resource and refuge patches at other hierarchical levels. This spatial heterogeneity is supported by a number of biologically relevant spheres of influence that include the detritusphere, the drilosphere, the porosphere, the aggregatusphere and the rhizosphere. Each has fairly distinct properties that operate at different spatial scales. We discuss how these properties may function in regulating the interactions among organisms and the biogeochemical processes that they mediate. It is through the formation of a spatially and temporally heterogeneous structure that biodiversity may contribute most significantly to the functioning of soil ecosystems.
Real advances in understanding the significance of biodiversity to biogeochemical cycling will come from taking a broader view of biodiversity. Such a view will necessarily encompass many levels of resolution including: 1) the importance of biodiversity to specific biogenic transformations, 2) the complexity and specificity of biotic interactions in soils that regulate biogeochemical cycling, and 3) how biodiversity may operate at different hierarchically arranged spatial and temporal scales to influence the structure and function of ecosystems.
Flexible Manufacturing System (FMS) is one of the very effective strategies and manufacturing management methods to allow the material handling system to become a highly competitive and cost-effective fabrication environment. To adapt the FMS effectively, a new type of conveyor, which is one of the major components in material handling system, call spiral Conveyor will be developed. The conveyor will be equipped with smart system by using Programmable Logic Controller (PLC) with customize the cylinder actuator design. The new design had will analyzed and verified by through Finite Elements Analysis and the prototype had been produced by using 3D printing technique.
In the present study, varying amounts of zirconia (ZrO2) (1, 2, 3 and 5 wt%) was doped with hydroxyapatite (HA) and their sintering behaviour was evaluated. A simple wet precipitation method was used to produce the HA and ZrO2 powders. The ZrO2 powder was added to the HA powder via a ball milling process. Green samples were prepared by powder pressing technique and pressureless sintered for 2 h at 750 °C, 1050 °C and 1250 °C. The Volume Fraction Porosity (VFP), Young’s modulus and microhardness of sintered samples were measured. It was found that sample containing 1 wt% ZrO2 sintered at 1250 °C exhibited the highest Young’s modulus of 100 GPa and microhardness of 2.78 GPa, corresponding to the lowest VFP.KeywordsZirconiaHydroxyapatiteSinteringMechanical properties
Zirconia-toughened alumina (ZTA) has been widely studied owing to their excellent strength and toughness for mechanical applications. However, to realise these excellent properties, ZTA is often sintered at high temperatures (>1550 °C) which may be uneconomical. This study aims to aid the sintering of ZTA composite containing zirconia content (up to 20 vol%) by the addition of 0.6 vol% copper oxide (CuO) and sintered via two-stage sintering process. The result revealed that ZTA containing 10 vol% zirconia and when sintered at T1 = 1450 ℃ and T2 = 1350 ℃ with a soaking time of 6 h were found to exhibit the best mechanical properties (i.e. Vickers hardness, elastic modulus and fracture toughness of 18.5 GPa, 409 GPa and 8.1 MPam1/2, respectively). In addition, the ZTA grain size was reduced by more than 10% without compromising on the relative density of above 99%. The study concluded that ZTA could be sintered at low temperatures by controlling the sintering profiles and the use of CuO as sintering additive.KeywordsZirconiaZTAY-TZPCopper oxideTwo-stage sintering
This research aims to address the noise pollution by developing an acoustic absorber made of polylactic acid (PLA)/polyhydroxyalkanoates (PHA)-wood fibers (PLA/PHA-WF) by compression molding (CM) and additive manufacturing (AM). Physical, mechanical, thermal, water absorption, and biodegradation properties of the developed acoustic absorbers by CM and AM were characterized and compared. Upon providing an air gap, thin absorbers developed by AM exhibit an increased and narrow acoustic peak than the CM absorbers because of theHelmholtz resonance effect due to the decreased density and increased porosity in the AM absorber. The results also show that the mechanical and thermal properties of theabsorbers developed by CM and AM were almost similar and absorber developed by AM shows anincreased rate of water absorption and biodegradation compared to absorber developed by CM due to the presence of porosity in the AM structure.
A reinforced learning experience (Lx) framework (through a) developed, executed, and evaluated against pre-COVID19 and COVID19 operational semesters. This framework is designed through the unlearning approach of the inhouse design thinking tool and lateral executive of curricular delivery, assessments, and evaluations.
The application of big data in urban transportation and development of smart cities has been attracting global interest. The overburdened transport infrastructure due to rapid urbanisation should be integrated with innovative technologies and brand-new ideas such as smart city in order to enhance its performance. Big data is now the emerging exemplar in intelligent transportation systems for effective management of all data for implementing safer, cleaner, and well-planned transport services, as well as providing personalised transport experience for road users. In this chapter, the authors lay forward the current research endeavours on big data for urban transportation infrastructure, its implementation, baseline framework, and usage on fields such as planning, routing, network configuration, and infrastructure maintenance. This chapter evaluates the contributions of big data on urban transport modelling techniques, tools, and mobility. Finally, the present trends and future challenges of big data are summarised for helping researchers to facilitate the development of smart cities.
In recent years, Artificial Intelligence has been widely used for determining the current state of Li-ion batteries used for Electric Vehicle applications. It is crucial to have an accurate battery state estimation to prevent over-charging/over-discharging of Li-ion batteries, which would contribute to increased lifetime, thus reducing the running costs of Electric Vehicles. This review paper focuses on some of the commonly proposed Artificial Intelligence data-driven based State of Charge and State of Health estimation that has not been covered in much detail previously. The recent works indexed under Web of Science that used Support Vector Machines, Gradient Boosting and Artificial Neural Networks (with a deep insight on the use of recurrent architectures) for battery state estimation are reviewed. A handful of recent works that implemented their proposed battery state estimation algorithm on a hardware prototype is also discussed, along with the current challenges faced in implementation. Since various input features have been suggested for State of Charge and State of Health estimation in the recent literature, a detailed analysis is presented in this paper. Key observations with research gaps are made from the reviewed literature, with identification of major challenges. Future research paths are deduced, with the goal of increasing the feasibility of implementing Artificial Intelligence-based battery state estimation in Electric Vehicles.
The Alumina zirconia composite was proposed in biomedical application to overcome the low temperature degradation and poor toughness experience by zirconia and Alumina, respectively. The main issue in developing zirconia-Alumina composite is the homogeneous of the microstructure in the powder mixing. In these studies, Alumina zirconia composite will be prepared by using colloidal method with different vol% of zirconia contain ranging from 5% to 20%. The specimen was tested for its hardness and fracture toughness. Hardness tested by using micro indentation method and fracture toughness by measuring the dimension of the radial crack on the sample induced by Vickers. The specimen with 10% zirconia content yielded the maximum fracture threshold value of 5.0 MPa. m1/2.
In this study, samples of Zirconia Toughened Alumina (ZTA) Composite with Y-TZP content between 0 to 20 vol% and 0.6 vol% copper oxide (CuO) were prepared and sintered via various sintering profiles of Two-Stage Sintering. The microstructural and mechanical properties such as bulk density, Vickers hardness, Young’s modulus and fracture toughness of these samples were determined to investigate the efficacy of the sintering profiles employed. Based on the data obtained, ZTA containing 10 vol% Y-TZP content and 0.6 vol% CuO with a heating rate of 10 ℃/min, T1 1450 ℃, T2 1350 ℃ and holding time of 6 h were found to be the optimum sintering profile. The sample’s grain size were reduced by >10% and mechanical properties were able to meet international standards such as ISO 6474 as the sample achieved full densification (>99%. T.D.), Vickers hardness, Young’s modulus and fracture toughness of 18.5 GPa, 409 GPa and 8.1 MPam1/2, respectively. This research could lead to development of ZTA composites with enhanced mechanical properties.KeywordsZTAZirconiaAluminaTwo-stage sintering
Zirconia (ZrO2) powder from 1 weight percentage (wt%) to 5 wt% in comparison of wt% of Hydroxyapatite (HA) was added to form HA-ZrO2 composites to produce HA-ZrO2 composites that will exhibit desirable mechanical properties which can be useful in biomedical applications. Simple wet precipitation method was employed to produce HA and ZrO2. Low wt% ZrO2 of 1, 2, 3 and 5 wt% were used to prepare the composites which were pressureless sintered at 750 °C, 1050 °C and 1250 °C respectively for 2 h. Volume Fraction Porosity (VFP) was investigated and mechanical properties of Young’s modulus and microhardness were used for evaluation. It was found that composite that consist of 1 wt% ZrO2 sintered at 1250 °C showed the highest Young’s modulus and microhardness as both corresponds to the lowest VFP. The Young’s modulus and microhardness of this composite were found to be 100 GPa and 2.78 GPa respectively. This can be advantage in the field of orthopaedics in which implant materials have to withstand high stress.KeywordsHA-ZrO2 compositesVolume fraction porosityMechanical properties
In this study, the relation between macroscopic parameters (speed, flow, density, occupancy) and microscopic parameters (lateral clearance, average gap, space headway, lateral movement duration, overtaking time, overtaking distance, relative speed) is evaluated by considering vehicle-type-dependent factor using the trajectory data collected at a five-lane urban merge and non-merge sections in Malaysia. Traffic data extractor software is utilized to extract the flow, speed, and trajectory data of the vehicles at both the merge and non-merge sections of urban highway. Both SPSS software and MATLAB software were used to conduct statistical and numerical modeling of the extracted field data. The results show a significant variation in vehicle-type dependant driving behaviors at merge and non-merge section. These parameters are useful in the development of simulation models for the merging part on a multi-lane urban highway. The findings are also useful for estimating the potential collisions under mixed traffic conditions in road safety management.
Background and objective
Central aortic blood pressure waveforms convey imperative information about cardiovascular risk, but these measurements are obtained invasively. The study aims to develop an electrical impedance function (EIF) to estimate the central (aortic) blood pressure waveform from the radial blood pressure waveform without the need of invasive procedures.
Methods
This paper shows a method of using the four-element Windkessel model to derive an EIF using circuit analysis to estimate the central aortic blood pressure. The four elements were identified from radial waveforms by using the Nelder-Mead simplex algorithm and then used to construct the EIF to obtain the aortic pressure waveform, given the radial waveform.
Results
Waveforms generated by EIF gave the lowest values for Root Mean Square Error (RMSE) (5.69) and Mean Average Percentage Error (MAPE) (0.0402) compared to the generalized transfer function (GTF) and N-point moving average (NPMA), and the lowest MAPE and a comparable RMSE when compared to the Adaptive Transfer Function (ATF). Moreover, EIF has a significantly lower computing time (0.008 ms) when compared with GTF, NPMA and ATF.
Conclusions
The proposed function had comparable or better performance to existing methods when tested on both simulated and actual patient data, and was able to give a better signal shape retention at the dicrotic notch (99.94 % correlation), which is a crucial feature for cardiovascular disease detection.
Significance
Overall the EIF performance validates its use in estimating central aortic pressure waveforms, making it potentially viable for better embedded systems for non-invasive central blood pressure monitoring due to its low computation time and high accuracy.
This chapter discusses how an engineering curriculum is successfully embedding EQ in the module delivery. Individual and group activities were adopted to enhance EQ in students while group projects were introduced to provide a quantitative measurement on the effectiveness of EQ training. Furthermore, the approach also received numerous approvals at both international and national teaching and learning exhibitions.
The soil microfungi of the A horizon of an oak-birch forest on Long Island were isolated by dilution plate from 630 soil samples collected over a period of 40 mo. Because these fungi co-occurred in time and space and showed similarities in their nutritional, reproductive, and survival strategies, they are considered a specific community designated the opportunistic decomposers. Dominance in this community was determined by numerical superiority. A discussion of the factors regulating propagule density in soil and a rationale for using propagule density as the quantitative measure of prominence when large numbers of samples are analyzed is presented.
Community composition and structure were based upon analysis of 10,684 isolates from 80 samples collected during the spring, summer, fall, and winter of 1975. This assemblage, reduced to 89 taxa, contained four broad-amplitude species; Penicillium terlikowskii, P. daleae, Trichoderma pseudokoningii and Oidiodendron chlamydosporicum?. These species plus Torulomyces lagena, Acremonium diversisporum and Mortierella ramanniana are the characteristic fungi. Seventy-eight percent of the isolates were mycelial Deuteromycetes; the remainder included Zygomycetes and Ascomycetes (6% and 5% of all isolates, respectively) and asporogenous yeasts. Propagules of the opportunistic decomposers were abundant in the A horizon. They remained constant at approximately 340,000 during most of the year but increased to over one million per g dry soil in April. Species diversity was highest in the spring, lowest in the summer, and essentially constant at 16 species per 100 isolates during the other seasons. Stability characterized the community. Particular combinations of species persisted throughout the course of the study resulting in high coefficients of similarity when populations from different years were compared using a modified Sorensen's Index.
Seasonal changes in propagule densities for 25 commonly encountered fungi were studied over a 40-mo period. The following patterns were revealed: (1) five species had essentially constant numbers throughout the year; (2) nine increased significantly in the spring; (3) the oidiodendrons showed a winter peak in density; (4) four species, including Beauveria bassiana and Metarrhizium anisopliae, appeared only in the spring; and (5), five species had apparently random distributions. An attempt was made to correlate some of these patterns with other changes thought to be occurring in the ecosystem a the same time.
The soil microfungi in five northern Wisconsin open bogs and ten conifer swamps have been surveyed. Two hundred isolates from eight sites in each community were identified or characterized and frequencies for all entities were calculated. The number of entities per community ranged from 10 to 68, and the numbers of entities per unit (1000 isolates) were 108 (open bogs), 104 (Picea-Larix swamps), and 181 (Thuja-Abies swamps). Only 5–9 species in each unit had average frequencies of 30% or higher. Mycelia Sterilia 3157, Eurotiaceae gen. n.? 4084, Penicillium odoratum, Penicillium (Paecilomyces ?) sp. 3908, and Geotrichum candidum are prevalent in open bogs; Mortierella vinacea III, Periconia sp. 3284, Penicillium odoratum, Cryptococcus laurentii, Oidiodendron flavum variant, and one unidentified yeast in Picea-Larix swamps; and Torulopsis aeria, Cryptococcus laurentii, Trichoderma viride, T. album, and one unidentified yeast in Thuja-Abies swamps. In the populations as a whole, Ascomycetes, yeasts, Dematiaceae, and Mortierella species were common, whereas Aspergillus, Fusarium, and Sphaeropsidales were rare. Approximately one-half of the identified species appear to be absent or rare in mineral soils, but several are well-known wood, wood-pulp, or litter forms. Species composition in the microfungal communities is correlated with species composition and maturity in the overlying higher plant community.
Very different microfungal species were obtained from forest soils in Rhode Island when two different isolation temperatures (0 C and 25 C) were used, even though isolates were obtained from the same samples. At 0 C, Zygomycetes, particularly Mucor and Mortierella species in the sections Hygrophila and Stylospora, were favored. Most fungi isolated at 0 C were psychrotrophs capable of growing from 0 C to temperatures greater than 25 C. However, psychrophiles, mostly Mortierella and Mucor spp., were also isolated, and two new Mortierella species were identified. Isolations at 25 C resulted primarily in the recovery of Deuteromycetes and Mortierella species in the section Isabellina. Most of these isolates were mesophiles with growth minima between 5 and 10 C and maxima above 25 C. It is concluded that isolation temperature can seriously bias our perception of fungal species abundance, dominance and distribution in forest soils. Soil temperatures measured at 10 cm depth for 2 years in a Rhode Island forest remained at or below 10 C for 5 months of each year and did not rise above 19 C. Water potentials in the upper 15 cm of soil were greater than -0.4 MPa over the same period and were not limiting for the growth of most fungi. Therefore, low temperature fungi are potentially active throughout the year in soil of this temperate forest, whereas the activity of mesophiles may be restricted to periods when temperatures are above approximately 10 C. Isolations at 0 C should improve identification of fungi involved in decomposition processes at low temperatures.
A number of factors affecting production of extracellular lipase by Aspergillus niger were investigated. Consecutive optimization of nitrogen and carbon sources and salts enhanced the lipase activity and under optimum conditions, activities as high as 35.4 U ml-1 of culture medium were obtained in 48h at 30°C. K and Mg++ had a positive effect on lipase production whileCa++, Zn++, Mn++ and Fe+++ were found to be inhibitory. Olive oil was found to be the most effective inducer. The enzyme was optimally active at pH 7.0 and 37°C and was found to be stable between pH 4 to 9 and at temperature between 4 to 45°C The enzyme also showed remarkable stability in detergents such as Tween 80 and SDS.
Alfred Stieglitz (1864–1946) produced his well-known cloud photograps over a period of more than a dozen years, beginning in the 1922 and continuing until nearly the end of his carrer as a photographer. Initially he gave them musical titles, first ‘Equivalent’. These pictures were first shown under that title in the ‘Seven Americans’ exhibition at the Anderson Galleries in 1925, a show that also included the work of Arthur Dove, MArsden Hartley, John MArin, Charles demuth, Paul Strand and Georgia O'Keeffe. In the years that followed, Stieglitz produced hundreds of such images, and he continued to call them ‘Equivalents’ In time, he applied that term not only to his cloud imagery, but to all, or virtually all, of his pictures, as well as to art more generally. 1
Cellulolytic enzymes are produced by Poronia oedipus grown on soluble and insoluble forms of cellulose. Cellulase production is negligible when the organism is grown in the presence of glucose. Optimal cellulolytic activity occurs at 50-55 C. Hydrolysis of filter paper is greatest at pH 4.2; but with carboxymethylcellulose as a substrate, optimal cellulase activity occurs at pH 4.4 to 5.0. Total accumulation of reducing sugar in the cellulase assay with filter paper as a substrate does not rise above 1% of the substrate concentration; with CMC as a substrate, approximately 5% conversion is reported.
1 The distribution of soil microfungi in the successive ecological zones of eight dune systems on the British coast has been recorded with special reference to the acid system at Studland and the alkaline system at Sandwich. 2. A relatively rich and active fungal population was found in the dune xerosere, but it contained few species which appeared to be confined to the dune habitat. 3. The acid and alkaline dune mycofloras were distinct from one another. 4. A succession of species, comparable with that of higher plants, was found to occur across the dune systems from the pioneer communities of the foreshore to the climax communities of the fixed dunes. 5. A marked vertical development of the fungal population accompanied the horizontal succession, culminating in a stratified microfungal profile.
Fusarium culmorum, Cochliobolus sativus, Curvularia ramosa, Gaeumannomyces graminis var. tritici and Phialophora graminicola were tested for their ability to produce colonies on unsterilized filter paper. Colonies of the first three species sporulated well on the paper moistened with a mineral salts solution but in no species did colonies exceed a mean diameter of 17 mm.
The chief determinant of colony size seemed to be inoculum potential of the PD inocula which was determined by the nutrition of the fungus. In all species except P. graminicola, inoculum potential of the inocula declined significantly with age of mycelium. A correlation was found between linear growth rate on PD agar, taken as a parameter of general metabolic rate, and percentage reduction in diameter of colonies on filter paper, due to ageing of the mycelium. Linear growth rate has been used as the denominator of the cellulolysis adequacy index and the implications of these findings for saprophytic survival on cellulosic substrates have been discussed.
The South African Cape Floral Kingdom is the world's smallest and most diverse plant Kingdom, but is greatly under threat from urbanisation and agriculture. It covers only 90000 km2 and has a Mediterranean climate. This area has a long history of botanical studies, but little research has been undertaken on the associated fungi. Therefore, a biodiversity study of the fungi has been initiated. The catalyst for this study has been the diversity of unusual fungi encountered whilst studying the fungal pathogens of Proteaceae. These pathogens include species, or entire genera of fungi that are specific to genera of Proteaceae. The diversity and uniqueness of the Proteaceae pathogens may indicate a similar diversity in saprobic fungi in this unusual habitat. Therefore, microfungi associated with genera of Proteaceae in various habitats are being systematically sampled over a two-year period. The initial results of this study are presented.
The commercial processing of starch to mono- and oligosaccharides depends on the availability of three major enzymes - glucoamylase, alpha-amylase and glucose isomerase. Each of these enzymes has a unique pH and temperature optimum for use, and so unit operations of a starch plant reflect the varying operating conditions for each individual enzymatic step. This article will discuss how recent advances in molecular biology and protein engineering have allowed enzymes with improved operating parameters to be introduced to commercial applications, providing the starch processor with enhanced plant efficiency, lower operating costs and higher-quality products.
Comparisons were made of the soil fungi isolated from three diverse alpine sites. The sites studied were a grass slope (Bromus association) at 1900 m, an alpine meadow (Dryas association) at 2530 m, and a summit ridge (Oxytropis association) at 2840 m. The effects of season, soil depth, and substrate type on the distribution of fungi were also examined. In a principal component analysis, most of the variation in mycoflora composition was attributed to differences among the sites. All taxa tested using a factorial analysis of variance showed significant differences in isolation frequency among the three sites. About half showed significant variation with season. For total fungi, the effect of seasonal change was the smallest of the four factors studied. Seasonal changes were not unidirectional, instead the composition of the fungal community shifted to one extreme in summer, with the direction of this change later reversing to another extreme in the fall opposite to that of the summer. The frequency of occurrence of most taxa was inversely related to soil depth. However, Chrysosporium pannormn, Penicillium restrictum. Penicillium canescens, and sterile fungi showed the opposite trend.The fungal communities were characterized by a few frequently isolated species, and a much larger proportion of infrequently isolated forms. All the dominant species were also widely distributed in temperate soils. The less frequently isolated species were usually highly aggregated in their distribution, with localized densities often exceeding those of the most frequently isolated forms. This pattern of distribution may have resulted from specialization on a niche dimension that was not widely distributed in the soils studied. Dominant species were less aggregated and more widely distributed, possibly reflecting a broad or diverse niche space for these species.
Physiological groups of soil microorganisms were investigated in a forest (Pinus pinaster Sol.) to asses their response to wildfire-induced soil changes. Microbial fluctuations were recorded 1 month and 1 year after the fire, both in the field and during controlled soil incubations. In both the burned and the unburned soil, starch-mineralizing microbes predominated over cellulose-mineralizing microbes; there were a relatively high number of ammonium-producers, whereas nitrite and nitrate producers were scarce. In the short term, burning produced a decreasing to nearly undetectable number in cellulase-producers whilst amylase-producers, and especially, ammonifying microbes increased, and the nitrifying groups did not change. One year after the wildfire, the burning effect was slightly overcome by cellulolytic microorganisms and the amylolytic population was slightly decreased; the improvement of ammonifiers was reduced, ammonium oxidizers were positively affected and nitrite oxidizers continued to be unaffected by the fire. The trends of populations during soil incubation indicated that, in the long term, the effect of burning will probably be nil on ammonifiers, somewhat negative on cellulolytic and amylolytic microbes and slightly positive on nitrite- and nitrate-formers.
Germination of conidia and growth of hyphal fragments of Cochliobolus sativus were inhibited by six natural soils. The viability of fungal propagules during incubation for up to 50 days in three of these soils was investigated. Viability of hyphal fragments rapidly declined in both natural and steamed soils. Conidia remained viable throughout incubation at room temperature on steamed soils but some factors, in natural soils caused the death of most conidia by 50 days. Death of conidia was accelerated at high incubation temperature. Direct observations of non-viable conidia suggested that death was caused by some component of the soil microflora.