Cleantech Investments in Denmark, Finland, Norway, Sweden: Are they performing well?

The development of clean technology (cleantech) is necessary in order to address many prominent environmental challenges. However, financing can be a hurdle for the development of cleantech companies. Venture capital (VC) plays an important role in cleantech development. While the four large Nordic countries are regarded as performing well in terms of cleantech innovation there are signs that VC investments are not performing well in the Nordic region. Therefore, this thesis explored whether the private Nordic VC funds are performing well or not and why they perform successfully or unsuccessfully. The results from the performance review and the interviews do not support the initial information that the Nordic funds are not performing well. Only one of the interviewed funds does not have companies with a trend of growing in its portfolio. The remaining five interviewed Nordic funds have some companies in their portfolio with a growing trend. On the other hand, it is not certain that these funds are performing well as only historical trends of companies that are still in the portfolios are considered, while the actual performance of funds finally depends on the exits of the portfolio companies. Several factors that differ between the poorly performing Nordic fund and regarded successful European funds, including the fund size, specialization in investments, management of portfolio companies and the background of the fund. When comparing the other Nordic funds to the European funds, some differences could be identified too. For example, the funds from other European countries review more proposals than the Nordic ones in general. The European funds are also more open to initial public offerings (IPO) as an option for exiting portfolio companies

Effects of Tong Shapes on Hydraulic Log Grapple's Performance in Loading and Unloading Operations

Three log grapple tong shapes used in logging operations; horizontal ellipse, circle, and vertical ellipse, were analyzed mathematically and mechanically. The three same tongs as defined were designed and tested to evaluate their performance in terms of grabbing unrestrained log piles. Three operational variables; grabbing force, grabbed log weight, and unit grabbing force were examined using five diameter classes of logs for each set of tongs. Results indicated that the grabbing performance of log grapples with horizontal ellipse tongs is better than the grapples with circular tongs or vertical ellipse tongs

New molecules to combat the bacterial antibiotic resistance problem

Platensimycin/platencin are recently discovered natural products that inhibit membrane formation in bacteria and cyclic diguanylic acid (c-di-GMP) is a master regulator of bacterial biofilm formation. The rise of bacterial antibiotic resistance and the dwindling pipeline of new antibiotics make these molecules of interest to the scientific community. This dissertation reports the design, synthesis and biological evaluation of analogs of platensimycin/platencin and c-di-GMP. Platensimycin and platencin have garnered interest from synthetic chemists due to the complexity of their molecular architecture, coupled with their exciting biological profile (inhibition of bacterial fatty acid synthases). We have developed a concise synthetic approach towards the platensimycin/platencin class of antibiotics. The highlight of our synthesis is the use of dynamic ring-closing metathesis to prepare a bicyclo intermediate and a tandem nucleophilic addition of organolithium to a ketone moiety, followed by a subsequent ring opening of a nearby epoxide to generate complex tricyclic framework. The synthesis of platensimycin or closely related analogs requires multi-steps (average of 17 overall steps). Using a function-oriented synthetic approach, we developed short syntheses of N,N-dialkyl benzoic acid derivatives of platensimycin, and we demonstrate that these readily prepared molecules have comparable antibiotic properties to the difficult-to-synthesize platensimycin/platencin. C-di-GMP has been dubbed the master regulator of bacterial "lifestyle" due to the key role that this molecule plays in bacterial biofilm formation and virulence formation. In order to study c-di-GMP signaling in bacteria, with the ultimate goal of using key insights gained from such studies to develop anti-biofilm or anti-virulence agents, we prepared analogs of c-di-GMP and studied their biophysical and biological profiles. Interestingly, we reveal that conservative modifications to c-di-GMP affect both the biophysical and biochemical properties of this molecule. We also demonstrate a concept called "conformational steering" as a powerful principle to selectively target different classes of receptor proteins that bind to c-di-GMP

FIB-SEM Three-Dimensional Tomography for Characterization of Carbon-Based Materials

A review on the recent advances of the three-dimensional (3D) characterization of carbon-based materials was conducted by focused ion beam-scanning electron microscope (FIB-SEM) tomography. Current studies and further potential applications of the FIB-SEM 3D tomography technique for carbon-based materials were discussed. The goal of this paper is to highlight the advances of FIB-SEM 3D reconstruction to reveal the high and accurate resolution of internal structures of carbon-based materials and provide suggestions for the adoption and improvement of the FIB-SEM tomography system for a broad carbon-based research to achieve the best examination performances and enhance the development of innovative carbon-based materials

A Review of Log Grapples Used in China

The history and development of log grapples used in China and their working parameters are given. An analysis is made of the main technical features. Results show that the electro-mechanical log grapple, driven by an electric drum, is the most suitable for the special working conditions found in Chinese forestry at the present time

An Interactive Simulation System for Modeling Stands, Harvests, and Machines

An interactive computer simulation program models stand, harvest, and machine factors and evaluates their interactions while performing felling, skidding, or forwarding activities. A stand generator allows the user to generate either natural or planted stands. Felling with chainsaw, drive-to-tree feller-bunchers, or harvesters and extraction with grapple skidders or forwarders are currently modeled in the system and others may be added. Simulations are performed by moving machine images within stand maps on the computer screen. The residual stand, machine running paths, and extraction travel intensity are recorded for later analysis. Examples of simulations with common logging machines are illustrated

Modeling and Validating the Grabbing Forces of Hydraulic Log Grapples Used in Forest Operations

The grabbing forces of log grapples were modeled and analyzed mathematically under operating conditions when grabbing logs from compact log piles and from bunch-like log piles. The grabbing forces are closely related to the structural parameters of the grapple, the weight of the grapple, and the weight of the log grabbed. An operational model grapple was designed and tested to validate grabbing forces of the mathematical models while grabbing logs from five alternative diameter classes under two different working conditions. The working conditions and log sizes affected the grabbing forces significantly. Validation results suggest that the mathematical models developed can be used to estimate the grabbing forces required in the design process of log grapples. The results can be used by equipment manufacturers and researchers involved in the engineering design of grapples used in harvesting operations

Deformation and Failure Behavior of Wooden Sandwich Composites with Taiji Honeycomb Core under a Three-Point Bending Test

A new type of Taiji honeycomb structure bonded outside with wood-based laminates was characterized from a mechanical standpoint. Both theoretical and experimental methods were employed to analyze comprehensively the deformation behavior and failure mechanism under a three-point bending test. The analytical analysis reveals that a Taiji honeycomb has 3.5 times higher strength in compression and 3.44 times higher strength in shear compared with a traditional hexagonal honeycomb. Considering the strength-weight issue, the novel structure also displays an increase in compression strength of 1.75 times and shear strength of 1.72 times. Under a three-point bending test, indentation and core shear failure played the dominant role for the total failure of a wooden sandwich with Taiji honeycomb core. Typical face yield was not observed due to limited thickness-span ratio of specimens. Large spans weaken the loading level due to the contribution of global bending stress in the compressive skin to indentation failure. A set of analytical equations between mechanical properties and key structure parameters were developed to accurately predict the threshold stresses corresponding to the onset of those deformation events, which offer critical new knowledge for the rational structure design of wooden sandwich composites