Zero Stage Research Articles

A Trusted Execution Environment RISC-V System-on-Chip Compatible with Transport Layer Security 1.3

The Trusted Execution Environment (TEE) is designed to establish a safe environment that prevents the execution of unauthenticated programs. The nature of TEE is a continuous verification process with hashing, signing, and verifying. Such a process is called the Chain-of-Trust, derived from the Root-of-Trust (RoT). Typically, the RoT is pre-programmed, hard-coded, or embedded in hardware, which is locally produced and checked before booting. The TEE employs various cryptographic processes throughout the boot process to verify the authenticity of the bootloader. It also validates other sensitive data and applications, such as software connected to the operating system. TEE is a self-contained environment and should not serve as the RoT or handle secure boot operations. Therefore, the issue of implementing hardware for RoT has become a challenge that requires further investigation and advancement. The main objective of this proposal is to introduce a secured RISC-V-based System-on-Chip (SoC) architecture capable of securely booting a TEE using a versatile boot program while maintaining complete isolation from the TEE processors. The suggested design has many cryptographic accelerators essential for the secure boot procedure. Furthermore, a separate 32-bit MicroController Unit (MCU) is concealed from the TEE side. This MCU manages sensitive information, such as the root key, and critical operations like the Zero Stage BootLoader (ZSBL) and key generation program. Once the RoT is integrated into the isolated sub-system, it becomes completely unavailable from the TEE side, even after booting, using any method. Besides providing a secured boot flow, the system is integrated with essential crypto-cores supporting Transport Layer Security (TLS) 1.3. The chip is finally fabricated using the Complementary Metal–Oxide–Semiconductor (CMOS) 180 nm process.

Wood decomposition, carbon, nitrogen, and pH values in logs of 8 tree species 14 and 15 years after a catastrophic windthrow in a mesic broad-leaved forest in the East European plain

There are limited studies of decomposition of coarse woody debris (CWD) in natural conditions of multi-species mesic broad-leaved forests. We investigated 49 lying logs of 7 angiosperm and 1 gymnosperm species 14 and 15 years after a mass windthrow in an old-growth broad-leaved forest. We observed high heterogeneity of logs in terms of decomposition stages: up to 4 stages in one transverse disk and up to 5 stages in longitudinal fragments of one log. Due to the high heterogeneity of logs, we investigated traits of wood samples rather than individual logs. Bulk density, carbon and nitrogen concentrations, and pH values were examined for 188 CWD samples of 8 species at 5 decomposition stages (from stage 1 least to stage 5 most decayed wood) and 24 control samples of live trees (3 replicates for each species; zero stage of decay). Changes of deadwood volume, carbon and nitrogen stocks over 14 and 15 years after the windthrow were estimated by re-surveying transects established in 2010. From the first to the fifth decay stage, the mean CWD density decreased for all species and averaged 54 ± 16 kg m−3 (SD) at the 5th stage of decay. Regarding decomposition rates, the tree species were arranged in descending rate from diffuse-porous (Populus tremula, Betula pendula, Tilia cordata, and Acer platanoides) to ring-porous (Ulmus glabra, Fraxinus excelsior, and Quercus robur) angiosperms and the coniferous Picea abies was after the diffuse-porous species series and before the ring-porous species. Carbon concentration ranged from 39 to 54 %, but did not change significantly during decomposition (mean value for all species in all decay stages was 45.8 ± 2.5 %). Nitrogen concentration (percentage of dry mass) increased with increasing decay stage and the mean value was 0.2 ± 0.1 % at the zero stage and 0.9 ± 0.5 % at the last decay stage. Despite the increase in N concentration, the mass N per volume decreased during decomposition for all samples considered together due to a significant decrease in wood density. The change in C/N values during deadwood decay reflected the transition of organic matter from the CWD to the SOM (soil organic matter) in forest ecosystems: the ratio C/N varied from 829 (Picea, zero stage) to 16 (Ulmus, last stage) with the mean values 286 ± 149 and 75 ± 45 at the zero and the last stages, respectively. We observed a quadratic trend in the variation of wood pH values by stages: pH mainly decreased from the initial values to the minimum in the middle stages of decay, and then increased in the advanced stages. The mean deadwood volume in the surveyed plots decreased 1.4-fold in the 14–15 years after the windthrow, but the mean stocks of carbon and nitrogen decreased 3 and 2-fold, respectively. Over time, the different decomposition rate of fallen logs leads to a decrease in the proportion of C and N stored in diffuse-porous species at the expense of an increase in this proportion in ring-porous species. This result is worth considering in a carbon management strategy: planting, maintaining stands, and retaining deadwood of ring-porous species, such as Quercus, Ulmus and Fraxinus, promote relatively long-term carbon storage.

Dead Wood Elements Composition in Different Tree Species and Stages of Decay in the Broad-Leaved Forests of the Kaluzhskie Zaseki Reserve

The content and mass concentration of eight chemical elements Al, Ca, Cu, K, Mg, Mn, P, and Zn were analysed in dead wood of eight tree species at five stages of decomposition. Wood samples were taken at the site of the mass windfall of 2006 in a multispecies broadleaved forest in the Kaluzhskie Zaseki nature reserve. Deadwood of seven deciduous trees species was studied: maple (Acer platanoides), birch (Betula pendula), common ash (Fraxinus excelsior), common aspen (Populus tremula), English oak (Quercus robur), linden (Tilia cordata), rough elm (Ulmus glabra), as well as one coniferous tree species – Norway spruce (Picea abies). A series of one-way analyses of variance was carried out to assess the influence of the species and the stage of deadwood decomposition (including the zero stage for control samples) on the density, content of elements and their mass concentration. Tree species most clearly differed in the content and mass concentration of Mn, Zn, Mg, Ca, and K: R2 varied from 50 to 23% for the content and from 53 to 19% for the mass concentration of elements of the indicated series. The leaders in the content of these elements were the following species: Mn – maple, birch, spruce, linden; Zn – birch and aspen; Mg – maple, elm; Ca – elm; K – linden, elm. The stages of wood decomposition turned out to be a significant factor of variation for the content of Mn, P, Cu, Zn and Ca: R2 varied from 22 to 16%. During the destruction of wood trunks, a significant increase in the content of these elements occurred. Maintenance of cycles of biophilic elements is more successfully implemented in the presence of deadwood of different species at different stages of decomposition.

Micronucleus test and assessment of changes in peripheral blood erythrocytes of dominant animal species in the Turkestan region

The article presents the results of a study of peripheral blood erythrocytes of dominant animal species in the Turkestan region. The relevance of this work is due to the construction of a nuclear power plant on the territory of Uzbekistan (Jizzakh region, Lake Tuzkan), since the areas of the Turkestan region fall under the potential influence of nuclear power plants and biota objects require monitoring at the ‘zero stage’ before the construction of a nuclear power plant. The data obtained are of great importance in assessing the impact of technogenic factors on biota. Given the location of uranium deposits in the Turkestan region, the uranium content was determined in samples (bones, soft tissues) of amphibians and fish. It has been established that the concentration of uranium in samples of biological objects is within the normal range. We have carried out work on the analysis of erythrocytes and micronuclei in the following biota representatives: desert lacerta (lat. Eremias intermedia), yellow ground squirrel (lat. Spermophilus or Citellus), lake frog (lat. Pelophylax ridibundus), rudd (lat. Redd pisces), snakehead (lat. Channa argus). According to the results of studies in the desert lacerta (lat. Eremias intermedia) and lake frog (lat. Pelophylax ridibundus), various pathological conditions of erythrocytes and micronuclei were observed in 11% of the total number of blood products studied.

ІЧ-СПЕКТРОМЕТРИЧНІ ТА ТЕРМОГРАВІМЕТРИЧНІ ДОСЛІДЖЕННЯ КОМПЛЕКСІВ КОБАЛЬТУ, КУПРУМУ ТА ЦИНКУ НА ОСНОВІ ГЛІФОСАТУ

The complexes with Co(II), Cu(II) and Zn(II) based on glyphosate (N-phosphonomethylglycine) have been synthesized and studied by means of IR-, electron diffusion spectroscopies, thermogravimetric and elemental analysis. The coordination behavior between glyphosate and carbacylamidophosphates was compared. By means of IR spectroscopy, it was found that regardless of the ratio of reacting components (metal salt and glyphosate) the coordination compounds of the same type for each metal are always formed. The spectrum of the glyphosate and complexes with it can be divided into two parts, corresponding to the different donor groups of the ligand. Between 1500 and 1800 cm-1 strong peaks are found, mostly associated with stretching motions of the carboxylate group, while the region 800–1200 cm-1 is dominated by peaks originating from the phosphonate. The changes in frequencies of phosphate P–O (Δ(PО)=127 cm-1 for Na4CuL2, 144 cm-1 for Na4CоL2 and 21 cm-1 for ZnHL); NH– and C=O (Δ(CО)=102 cm-1 for Na4CuL2, 133 cm-1 for Na4CоL2, and 123 cm-1 for ZnHL) peaks indicate the involvement of these groups in coordination. The ν(C–O)a is shifted to higher frequency and broadened. The thermal decomposition process of glyphosate was studied by the DT and TG analysis. The results showed that the thermal decomposition temperature of glyphosate was above 198°C. And the decomposition process was divided into three stages: the zero stage is the decomposition of impurities, and the mass loss in the first and second stage may be methylene and carbonyl, respectively. It has been found that the ligand in the mentioned complexes is coordinated tridentivly via the nitrogen atom of amino group and oxygen atoms of the carbonyl and phosphate groups. The electronic spectrum of diffuse reflection of the cobalt (II) complex showed only one peak in the 534 nm region, corresponding to 4T1g (F)→ 4T1g (P) transition. This fact indicating the octahedral environment of the cobalt atom in complexes and causes its pink coloration. On the base of TGA and DTA analysis, IR spectroscopy and elemental analysis, the following compositions of the complexes were proposed: Na4CuL2, Na4CоL2 and ZnHL. Based on the literature data and our studies it was assumed that above structures contain fivemembered chelate rings with the amine, carboxylate, and phosphonate groups of the glyphosate ligand involved in chelation. Unlike 3d-metal complexes with carbacylamidophosphates, the phosphoryl group of glyphosate does not participate in coordination.

Breast Cancer: Detection Markers, Prognosis, and Prevention

Breast cancer is the common invasive cancer with high mortality worldwide. High incidence of breast cancer in South and central America, Southren, Northren, Westren Europe, Ocenia and North America. Lowest breast cancer incidence in Africa and Asia. Risk factors includes: female sex old age, lifestyle, oralcontraceptive, hormone replacement therapy, mutations in the breast cancer susceptibility genes BRCA1orBRCA2.alcohol intake, hereditary factors, and exposure to chemicals. Breast cancer occurs because of an interaction between external factor and genetically susceptible host. Frequent symptoms of breast cancer is typically a lump and lumps found in the lymph node in the armpits. Diagnosis by physical examination of the breast and mammography. Further tests include histopathological examination, breast cells grading by TNM systeme.g., Zero stage a precancerous or marker condition, stage 1- 3 within the breast and regional nodes, and stage four is metastatic stage. Management of breast cancer depends on the stage of the cancer and age of the patient. Usually treated with surgery, chemotherapy or radiation therapy or both. A multidisciplinary approach is preferable. Metastatic cancer has less favorable prognosis. Prognosis is usually the probability of progression-free survival(PFS) or disease free survival(DFS).Prevention include change in life style, maintaining healthy weight, less alcohol consumption, and intake of marine omega-3 and soy-based foods Prophylactic mastectomy(removal of both breasts) helps in people with BRCA1 and BRCA2 mutations. Early detection of breast cancer has better prognosis.

Influence of the Contact Opening Speed on DC Vacuum Arc

Arc determines whether the vacuum switchgears can break current successfully, so it is significant to study its characteristics. In this paper, a hybrid high-speed actuator was designed, and a method of forced current zero was used to interrupt dc in a synthetic test circuit. With the different contact opening speeds, the processes of arc burning and current transferring were observed by a high-speed CMOS camera. Through the arc area obtained by an image processing technology, the influences of the opening speed on arc were researched, including the influences in the initial arc burning stage, in the forced current zero stage, and at the same electrode distance. The results indicate that with the increase of the opening speed in a certain range, the arc area in the forced current zero stage tends to be small, and the one in the initial arc burning stage spreads more quickly. Although the arc area increases with the opening speed in the initial arc burning stage, its impact on the whole dc current transferring process is slight when the contact opening speed is high. So, high opening speed is helpful to extinguish arc and transfer current. In addition, there is another discovery in the experiments. In a certain range, when the opening speed is higher, arc burns stably earlier, and the arc area is smaller in the stable burning stage. So, it is beneficial to inject the transferring current in this stage. Experimental results and analysis of the arc images prove that increasing the opening speed is useful to transfer the current successfully and recover the dielectric strength of the electrode distance.

Study on thermal decomposition and the non-isothermal decomposition kinetics of glyphosate

The thermal decomposition process and non-isothermal decomposition kinetic of glyphosate were studied by the Differential thermal analysis (DTA) and Thermogravimetric analysis (TGA). The results showed that the thermal decomposition temperature of glyphosate was above 198 °C. And the decomposition process was divided into three stages: The zero stage is the decomposition of impurities, and the mass loss in the first and second stage may be methylene and carbonyl, respectively. The mechanism function and kinetic parameters of non-isothermal decomposition of glyphosate were obtained from the analysis of DTA–TG curves by the methods of Kissinger, Flynn–Wall–Ozawa, Distributed activation energy model, Doyle and Satava-Sestak, respectively. In the first stage, the kinetic equation of glyphosate decomposition obtained showed that the decomposition reaction is a Valensi equation of which is two-dimensional diffusion, 2D. Its activation energy and pre-exponential factor were obtained to be 201.10 kJ mol−1 and 1.15 × 1019 s−1, respectively. In the second stage, the kinetic equation of glyphosate decomposition obtained showed that the decomposition reaction is a Avrami–Erofeev equation of which is nucleation and growth, and whose reaction order (n) is 4. Its activation energy and pre-exponential factor were obtained to be 251.11 kJ mol−1 and 1.48 × 1021 s−1, respectively. Moreover, the results of thermodynamical analysis showed that enthalpy change of ΔH≠, entropy change of ΔS≠ and the change of Gibbs free energy of ΔG≠ were, respectively, 196.80 kJ mol−1,107.03 J mol−1 K−1, and 141.77 kJ mol−1 in the first stage of the process of thermal decomposition; and 246.26 kJ mol−1,146.43 J mol−1 K−1, and 160.82 kJ mol−1 in the second stage.

Prenatal hypoxia affects amyloid metabolism and formation of cognitive functions in postnatal ontogenesis of rats

In medicine, primary prevention constitutes the first level of health care with the goal of preventing onset of a given disease process, whereas secondary prevention represents a second level of postonset early detection and treatment. Because preclinical Alzheimer’s disease (AD) is marked by the asymptomatic onset of AD pathogenesis, preventive measures undertaken at this stage should be regarded as secondary prevention; yet, they are commonly characterized as “primary prevention” or “prevention” in the literature on AD. Certain nontoxic, pleiotropic polyphenolic compounds suitable for long-term use among healthy individuals, derived from the ancient foods identified in the preceding chapter, possess the capability to safely upregulate alpha-secretase activity, decrease beta-secretase and gamma-secretase activity, and enhance clearance of amyloid beta from the brain, thus potentially establishing homeostasis between amyloid beta production and clearance. These pleiotropic capabilities as applied to the preonset “zero stage” of AD may provide a unique primary prevention competence prior to disease-process onset.

Electrical Backplane Equalization Using Programmable Analog Zeros and Folded Active Inductors

In this paper, we present a low-power small-area electrical backplane equalizer using programmable analog zeros and folded active inductors. We also present a dc-offset cancellation circuit, which occupies less chip area than the traditional offset cancellation schemes. The equalizer circuit was fabricated in a 1.0-V 90-nm CMOS process. With one zero stage, the equalizer occupies 0.015-mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> chip area and dissipates 12 mW of power. At 4.25-Gb/s data rate, the equalizer provides 7.8-dB gain boost at the Nyquist frequency. Without the use of any transmitter equalization, the analog zero equalizer demonstrated error-free transmission for pseudorandom-bit-sequence-31 data patterns over 34-in lossy FR4 backplanes.

True then, true now: A 40-year perspective on the early stage investment market

One of the constants in the angel marketplace is that they invest mostly for non-economic reasons. The operations of two Boston-based seed capital funds - Zero Stage Capital and Navigation Technology Ventures - which raise their funds from both institutional and angel investors are described. Some lessons about commercializing technology are reported.

Aerodynamic Design and Testing of an Axial Flow Compressor With Pressure Ratio of 23.3:1 for the LM2500+ Gas Turbine

The LM2500+ gas turbine, rated between 39,000–40,200 shaft horsepower (shp), was introduced for field service in 1998. This growth aero-derivative gas turbine is suitable for a variety of power generation applications, such as co-generation and combined cycle, as well as mechanical drive applications. At the heart of the LM2500+ 25% power increase is an up-rated derivative 17-stage axial compressor. This paper describes the aerodynamic design and development of this high-pressure ratio single-spool compressor for the LM2500+ gas turbine. The compressor is derived by zero-staging the highly efficient and reliable LM2500 compressor to increase the flow by 23% at a pressure ratio of 23.3:1. The aerodynamic efficiency of the compressor is further improved by using three-dimensional, custom-tailored airfoil designs similar to those used in the CF6-80C2 high-pressure compressor. The compressor achieved a peak polytropic efficiency above 91%, meeting all its operability objectives. The technical requirements and overall aerodynamic design features of the compressor are presented first. Next, the zero stage match point selection is described and the procedure used to set up the vector diagrams using a through-flow code with secondary flow and mixing is outlined. Detailed design results for the new transonic airfoils in the compressor using three-dimensional viscous analysis are presented. The compressor instrumentation and performance test results are discussed. The performance of the zero stage is separated from that of the baseline compressor with the CF6-80C2 airfoils to show the improvement in efficiency with the new airfoils.

Venture Funders — Are They the Solution?

The author briefly describes what venture funders do and how they do it to illuminate the process of high-tech business formation and development. By way of illumination, he gives two short histories of successful university spin-outs that his company, Zero Stage Capital, has helped launch. He then examines how this firm's knowledge and experience may apply in the context of the Scottish university and financial climate, and bearing in mind the goals of Scotland's Technology Ventures strategy. Finally, he discusses the US government support initiatives for small business, the Small Business Investment Company (SBIC) Program. He suggests an approach for its application in increasing the birth-rate of fast-track technology-based ventures in Scotland or in other countries that have the infrastructure to support and enhance the process.

Seed venture capital and university research commercialization: the Zero Stage – Penn State connection

Seed venture capital and university research commercialization: the Zero Stage – Penn State connection

Snowball Sampling

Snowball Sampling