Principal Portion Research Articles

Integrated study of the microfossils of the upper Aptian (Lower Cretaceous) of the Sobradinho and Serra do Mãozinha sections (Araripe Basin, northeastern Brazil): Biostratigraphic and paleoenvironmental inferences

The present study reports the results of an integrated analysis of the microfossil assemblages from the Sobradinho and Serra do Mãozinha sections of the upper Aptian Romualdo Formation in the Araripe Basin, northeastern Brazil. The analysis of the distribution pattern of palynomorphs (terrestrial and marine), foraminifera, and ostracods revealed the presence of the palynomorph Sergipea variverrucata and the ostracod Damonella grandiensis, which supported the allocation of the principal portion of the sections to the Sergipea variverrucata Palynozone (P-270) and Ostracod Biozone O11, which are both indicators of the Aptian (= Alagoas local Stage). The frequent occurrence of both marine and continental palynomorphs, as well as calcareous microfossils, provide evidence of a coastal marine to restricted transitional environments, under a semi-arid to arid climate, with two well-defined marine incursions. The highlight of the data from the Serra do Mãozinha section is a new record of the Subtilisphaera Ecozone. In this section, the monospecific Subtilisphaera microflora represents the interval of weak marine influence. By contrast, the Sobradinho section is characterized by the occurrence of calcareous microfossils, foraminiferal linings, and a previously undocumented association of dinocysts, including 13 genera with four taxa being identified to species. Of these, Atopodinium cf. Iuvene, Apteodinium maculatum, Batiacasphaera sp., Circulodinium sp., Impagidinium sp., Gonyaulacysta sp., and Pervosphaeridium sp. Were recorded in the Araripe Basin for the first time.

Diffusion Height and Order of Sulfur Dioxide and Bromine Monoxide Plumes from the Hunga Tonga–Hunga Ha’apai Volcanic Eruption

A violent volcanic eruption attracting considerable attention occurred on 15 January 2022 near the South Pacific island nation of Tonga. To investigate its environmental impact, we retrieved the sulfur dioxide (SO2) and bromine monoxide (BrO) vertical column densities of environmental trace gas monitoring instrument 2 (EMI-2) based on the differential optical absorption spectroscopy algorithm. The results showed westward and southeastward transport of principal parts of SO2 and BrO plumes, respectively, from the Hunga Tonga–Hunga Ha’apai (HTHH) eruption. On 15 January, most of the released SO2 entered the stratosphere (above 20 km) directly and spread rapidly westward (approximately 30 m/s). In contrast, the principal portion of the BrO spread southeastward slowly (approximately 10 m/s) within the 8–15 km altitude layer on 16 January. Our research results also suggest that during the HTHH eruption, BrO was released from the magmatic melt later than SO2. The total SO2 emissions from this eruption were approximately 0.24 Tg. The majority of SO2 and BrO plumes were transported within the Southern Hemisphere. This study is an important extension to the empirical database of volcanological and magmatic degassing research.

Identification of DC Thermal Steady-State Differential Inductance of Ferrite Power Inductors

In this paper, we propose a method for the identification of the differential inductance of saturable ferrite inductors adopted in DC–DC converters, considering the influence of the operating temperature. The inductor temperature rise is caused mainly by its losses, neglecting the heating contribution by the other components forming the converter layout. When the ohmic losses caused by the average current represent the principal portion of the inductor power losses, the steady-state temperature of the component can be related to the average current value. Under this assumption, usual for saturable inductors in DC–DC converters, the presented experimental setup and characterization method allow identifying a DC thermal steady-state differential inductance profile of a ferrite inductor. The curve is obtained from experimental measurements of the inductor voltage and current waveforms, at different average current values, that lead the component to operate from the linear region of the magnetization curve up to the saturation. The obtained inductance profile can be adopted to simulate the current waveform of a saturable inductor in a DC–DC converter, providing accurate results under a wide range of switching frequency, input voltage, duty cycle, and output current values.

Stable Ultrathin Perovskite/Polyvinylidene Fluoride Composite Films for Imperceptible Multi‐Color Fluorescent Anti‐Counterfeiting Labels

AbstractAs an essential part of information security in the Internet of Things (IoT), fluorescent labels possess a principal portion of anti‐counterfeiting due to its easy fabrication, low cost, and high yield. Here an ultrathin, stable, and patterned multi‐color fluorescent label with perovskite/polyvinylidene fluoride composite film is presented, which registers a resolution of 56.4 dpi and almost maintains its original fluorescent intensity after being immersed in water for 120 h. The variable color of fluorescent labels will improve the anti‐counterfeiting dimensions for the information security due to precise halogen constitutions. The imperceptible fluorescent labels are typically with a thickness of 1.2 um and a weight of 1.2 mg. They can be conformally adhered on the arbitrary curved substrate as the intelligent multi‐color fluorescent anti‐counterfeiting labels for IoT applications.

Research on the Pricing of Global Drought Catastrophe Bonds

The rapid development of catastrophe bonds provides a new idea for catastrophe risk dispersion, since its traditional means fail to afford the economic losses caused by the global drought catastrophe. With the deepening of the concept of the community with a shared future for mankind, there is an opportunity to issue global drought catastrophe bonds through international cooperation. Based on the data of global drought catastrophe losses from 1900 to 2018, this paper selects 21 countries as the primary participants of international cooperation and studies the pricing of drought catastrophe bonds by the POT model and high quantile estimation. The results show that the first-class bond has a 10% occurrence probability with the trigger point of $252.54 million, and the second-class one has a 35% occurrence probability with the trigger point being $117.13 million. In line with high quartile estimates, the one-year principal-protected catastrophe bonds with a face value of $1,000 are valued at $957.14 and $939.29, respectively. Besides, the principal portion of the lost bonds is $912.50 and $783.04, while the total of it is $867.86 and $626.79, respectively.

Flexible and efficient feedforward control of concentrating solar collectors

In this work, a static feedforward strategy for concentrating solar energy harvesting is proposed to confront the weather and load fluctuations. In order to counteract the disturbance and maintain the outlet temperature by regulating the mass flow rate, we derived and deployed a generalized disturbance-control equation, which could precisely describe the relationship of the disturbance-manipulated-controlled variables. Based on this equation, disturbance-rejection and setpoint-tracking tuning issues are individually studied. Besides, the rationality of this proposed almost-linear feedforward scheme has been numerically assured regardless of whether phase-change occurs. Finally, the result temperature deviation ranging between −2 °C and 2.5 °C is still tolerable in spite of harsh operating conditions with big share of thermal loss (6% relative to effectively-received radiation), poor optical efficiency (50%) and steep change ratio of effectively-received radiation (±20%). Compared with the widely-adopted PID feedback control scheme in numerical simulation, the feedforward scheme demonstrates the feasibility and superiority in targeted regulation. The feedforward strategy directly determines the manipulated mass flow rate to answer the imposed disturbance, whereas the optimized PID scheme costs respectively about 896 s ~ 1504 s and 658 s ~ 1174 s for the current disturbance-rejection and setpoint-tracking tuners. Moreover, the controlled outlet temperature costs about additional 200 s on the basis to approach to the setpoint, of which the delays are at least two times of the feedforward scheme. A detailed feedforward measurement-control program has also been presented. Notably, the present methodology is conducive to identifying the principal portion of regulation output, which is of particular value to further construct high-performance control schemes.

Wormlike Micellar Solutions, Beyond the Chemical Enhanced Oil Recovery Restrictions

While traditional oil recovery methods are limited in terms of meeting the overall oil demands, enhanced oil recovery (EOR) techniques are being continually developed to provide a principal portion of our energy demands. Chemical EOR (cEOR) is one of the EOR techniques that shows an efficient oil recovery factor in a number of oilfields with low salinity and temperature ranges. However, the application of cEOR under the harsh conditions of reservoirs where most of today’s crude oils come from remains a challenge. High temperatures, the presence of ions, divalent ions, and heterogeneous rock structures in such reservoirs restrict the application of cEOR. Polymer solutions, surfactants, alkaline-based solutions, and complex multi-components of them are common chemical displacing fluids that failed to show successful recovery results in hostile conditions for various reasons. Wormlike micellar solutions (WMS) are viscoelastic surfactants that possess advantageous characteristics for overcoming current cEOR challenges. In this study, we first review the major approaches and challenges of commonly used chemical agents for cEOR applications. Subsequently, we review special characteristics of WMS that make them promising materials for the future of cEOR.

Transcriptional analysis and histochemistry reveal a dominant role for cell wall signaling in mediating Pythium myriotylum resistance in Zingiber zerumbet

Although post infection changes in cell wall constituents are known to induce the immune response in plants against necrotrophs, little is known about the role of the cell wall in mediating resistance in Zingiber zerumbet (L.) Smith (Zingiberaceae) against the soil-borne necrotrophic oomycete Pythium myriotylum Drechsler, which causes soft-rot disease. Using RNA-Seq in combination with custom gene expression microarray we studied the temporal expression profile of 46 wall-associated genes in Z. zerumbet against P. myriotylum inoculation. Many genes that promote cell wall loosening were suppressed. Similarly, the genes involved in the biosynthesis and the signaling of phytohormones and the receptor-like kinases that mediate cell elongation were also suppressed. Several monolignol biosynthetic pathway genes were up-regulated. Histochemistry of the collar region of the aerial stem revealed H2O2 accumulation, increased lignification of the mesophyll cells surrounding vascular bundles in the leaf sheath and the significant increase in total lignin content. Pathogen hyphae were restricted to peripheral leaf sheath and were not extended into the pith through which the principal portion of the connective tissues passes in the aerial stem. Results highlight a coordinated transcriptional reprogramming of cell wall-associated genes to bring about changes in cell wall composition to minimize the cell wall damage caused by pathogen factors and to render the cell wall less amenable to pathogen penetration. The study illustrates a key role for cell wall fortification in preventing pathogen colonization in the vascular tissues, thus ensuring the transport system remains unaffected by the pathogen invasion.

基于能值分析的中国海洋生态经济可持续发展评价

PDF HTML阅读 XML下载 导出引用 引用提醒 基于能值分析的中国海洋生态经济可持续发展评价 DOI: 10.5846/stxb201512172517 作者: 作者单位: 辽宁师范大学海洋经济与可持续发展研究中心,辽宁师范大学海洋经济与可持续发展研究中心,辽宁师范大学城市与环境学院,辽宁师范大学海洋经济与可持续发展研究中心,辽宁师范大学城市与环境学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金重点项目（41571122）；部省共建人文社会科学重点研究基地项目（14JJD790038） Sustainable development of marine eco-economics based on an emergy analysis in China Author: Affiliation: Research Center for Marine Economy and Sustainable Development, Liaoning Normal University,Research Center for Marine Economy and Sustainable Development, Liaoning Normal University,College of Urban and Environment, Liaoning Normal University, Dalian, Liaoning,Research Center for Marine Economy and Sustainable Development, Liaoning Normal University,College of Urban and Environment, Liaoning Normal University, Dalian, Liaoning Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:海洋生态经济可持续发展的研究既是生态经济研究的重要领域，也是海洋经济研究的重点领域。运用能值分析构建中国海洋生态经济系统能值分析模型和指标体系，以中国沿海地区及其附近海域为研究区域，利用2013年的数据对中国海洋生态经济系统的可持续发展水平进行能值测度。研究表明：（1）2013年，中国沿海各省的海洋生态经济总能值为1.70×1024 sej，可更新资源能值占主体地位。（2）受沿海各省海洋经济发展水平不同和区域海洋资源储量影响，中国沿海地区海洋生态经济能值密度分布差异较大，能值货币比率以上海为界，南高北低，高中低3种能值产出率结构并存且以中能值产出率结构为主。（3）中国海洋生态经济系统的生态承载力以高承载力和较高承载力为主，但局部地区海洋生态承载力偏低影响区域海洋生态系统平衡。中国海洋生态经济系统环境负载率较大，环境负载率高的地区与我国海洋经济发达地区高度耦合。（4）从可持续发展指数来看，中国海洋生态经济发展的整体可持续性较好，局部地区环境负载率过大和生态承载力偏低严重制约着区域海洋生态经济的可持续发展。 Abstract:The sustainable development of marine eco-economic systems is fundamental for ecological and marine economic systems. The present study used emergy analysis to develop a model and index system for marine eco-economic systems. We selected coastal and sea areas in China and used data from 2013 to examine sustainable development of the marine eco-economic system. The results show that the: (1) in 2013, total emergy of marine eco-economic systems of coastal provinces is 1.70×1024 sej, and renewable resource emergy comprised the principal portion of emergy in China;(2) emergy density of different coastal provinces showed considerable differences, which were affected by regional marine resource reserves and economic development levels. The emergy currency ratio was high in the south of Shanghai and low in the north. The emergy yield ratio of marine eco-economic systems had high, middle, and low structures, and was predominantly composed of the middle structures; (3) marine eco-economic systems of China are based on a relatively high marine ecological capacity. However, the marine ecological capacity in some areas is lower than other regions,which influenced the balance of regional marine ecosystems.The environmental load ratio of marine eco-economic systems was high, indicating a more developed marine economy;(4) from the index of sustainable development, the integral sustainability of the Chinese marine economy is good, but there is a heavy environmental load ratio, and the lower marine ecological capacity of some areas could affect the sustainable development of the regional marine economy. 参考文献 相似文献 引证文献

Three-dimensional microanatomy of longitudinal lanceolate endings in rat vibrissae.

The longitudinal lanceolate endings are ubiquitous sensory terminals in the sinus and nonsinus hairs of mammals that form a palisade around the hair follicle. To analyze how the nerve endings detect hair movements, the present study re-examined their fine structure and relationships with surrounding connective tissue in rat vibrissae by using a combination of three methods: immunohistochemistry for S-100 protein, scanning electron microscopy of NaOH-macerated specimens, and transmission electron microscopy of serial sections. Observations showed the lanceolate endings to be represented by triplet units with a flattened axon terminal flanked on each side by a Schwann cell lamella, as reported previously. Two distinct parts were discriminated in the lanceolate ending: a principal portion in which the axon terminal protruded numerous fine fingers from between the Schwann cell coverings, and an apical cone that enclosed a large axon finger in an attenuated Schwann sheath. Long foot processes of Schwann cells fanned out distally from each apical cone. The principal portions of the lanceolate endings were firmly linked to the surrounding connective tissue by the narrow edges equipped with axon fingers, suggesting their continuous deformation by sustained hair deflections. In contrast, the apical cones were freely suspended in an amorphous matrix with only the end feet of the Schwann cell projections attached to rigid tissue elements. This part of the ending was proposed as a possible transducer site to generate rapidly adapting receptor potentials, both retreating and overshooting during the acceleration and deceleration phases of a given vibrissal movement.

Estrogen, but not androgens, regulates androgen receptor messenger ribonucleic acid expression in the developing male rat forebrain.

Testosterone is the principal gonadal hormone responsible for the masculinization of the rat nervous system. Sex differences in both the ligand and receptor availability may play a role in the process of sexual differentiation. In some brain regions, males express more androgen receptor (AR) messenger RNA (mRNA) than females by postnatal day (PND) 10. Gonadectomy on the day of birth (PND-0) eliminated the sex differences in AR mRNA expression at PND-10, and exogenous testosterone replacement restored this sex difference. Because testosterone can be converted to both androgenic and estrogenic metabolites in the brain, the present experiments were performed to determine whether androgenic or estrogenic metabolites of testosterone are responsible for region-specific regulation of AR mRNA content in the developing rat forebrain. We used a 35S-labeled riboprobe and in situ hybridization to assess relative steady-state levels of AR mRNA in animals killed on PND-10. In the principal portion of the bed nucleus of the stria terminalis (BSTpr) and medial preoptic area (MPO), males gonadectomized on PND-0 and treated daily with dihydrotestosterone propionate (DHTP), a nonaromatizable androgen, had low levels of AR mRNA that were not significantly different from AR mRNA levels in intact females. In contrast, males gonadectomized on PND-0 and treated daily with diethylstilbestrol (DES), a synthetic estrogen, maintained high, male-typical levels of AR mRNA in the BSTpr and the MPO. AR mRNA content in the VMH was not sexually differentiated in PND-10 rats and was unaffected by gonadectomy or hormone replacement. To further assess whether AR mRNA was autologously regulated, neonatal male rats were treated with the androgen receptor antagonist, flutamide. Flutamide at a dose of either 40 microg/day or 300 microg/day had no effect on AR mRNA expression in any area examined. Thus, AR mRNA is up-regulated by estrogen but is not regulated by androgen during the early postnatal period.

Regulation of androgen receptor messenger ribonucleic acid expression in the developing rat forebrain.

By postnatal day 10 (PND-10), males express more androgen receptor (AR) messenger RNA (mRNA) than females in the principal portion of the bed nucleus of the stria terminalis (BSTpr) and medial preoptic area (MPO), but not in the ventromedial hypothalamus. The development of these region-specific sex differences in AR mRNA expression may be critical for the organization of male-typical neural circuitry and may represent the onset of sex differences in the sensitivity of the rat brain to the actions of androgens. In this study, we used a 35S-labeled riboprobe and in situ hybridization to address whether postnatal testosterone exposure is important for the up-regulation of AR mRNA content in the developing rat forebrain. In the BSTpr and the MPO of PND-10 rats, males gonadectomized on PND-0 or PND-5 had lower levels of AR mRNA compared with intact or sham-operated control males. Daily replacement of testosterone to animals gonadectomized on PND-0 maintained AR mRNA content in the BSTpr and the MPO at levels equal to those in intact males. In contrast, there was no effect of gonadectomy or testosterone replacement on AR mRNA expression in the ventromedial hypothalamus. Thus, the postnatal hormonal environment may permit the development of region-specific sex differences in AR mRNA. Significant alterations in AR mRNA expression in the BSTpr and MPO in PND-10 male rats were induced by gonadectomy as late as PND-8. Males gonadectomized on PND-8 had levels of AR mRNA significantly lower than those in intact males, but significantly higher than those in intact females. Further, when animals were gonadectomized on PND-0 and given testosterone on PND-8 and PND-9, levels of AR mRNA were also intermediate between those found in intact males and intact females. The exact time course for transcriptional regulation of AR mRNA in the developing rat brain is unknown. However, others have shown significant regulation of AR mRNA within hours of hormone treatment, so that 2 days of hormone withdrawal or replacement are probably sufficient to achieve new steady state levels of message. Moreover, sexually dimorphic neuronal loss has been documented to peak in hypothalamic cell groups during the first postnatal week. Thus, it is likely that changes in the number of AR mRNA-expressing cells as well as the amount of AR mRNA expression per cell are responsible for the development of male-typical AR mRNA content.

Trigeminal projections to thalamus and subthalamus in the hedgehog tenrec

The objective of the present study was the identification and characterization of the trigemino-diencephalic target areas in the Madagascan lesser hedgehog tenrec in order to get a more comprehensive view on the mammalian somatosensory thalamus, its evolution and representation in different species. Such an analysis has been considered important because in lower mammals the head and face are relatively well represented, but their ascending trigeminal projections have scarcely been analysed. Following injections of different tracer substances into the rostral and caudal portions of the trigeminal nuclear complex the most prominent area of termination was found in the medial ventroposterior nucleus. These projections were patchy and scarcely overlapped the region previously shown to receive spinal and dorsal column nuclear afferents. On the basis of the laterality and the intensity of the projections, two subdivisions were distinguished, the principal portion and the accessory portion receiving a dense contralateral and a weak bilateral input, respectively. They were considered equivalents to the magnocellular and parvocellular subdivisions of the medial ventroposterior nucleus in more differentiated mammals. In the latter species, however, the overlap between trigeminal and parabrachial fibres appears less extensive than in the tenrec. In addition, a weak bilateral projection was shown from the caudal trigeminal nucleus to the caudal and dorsal subdivision of the nucleus submedius. There was little, if any evidence for a trigeminal projection to the intralaminar nuclei and we failed to identify a correlate to the posterior nuclear complex of higher mammals. On the other hand, there was a distinct contralateral projection to the ventral portion of the zona incerta. This projection was of similar strength as the projection to the medial ventroposterior nucleus; it supports the notion that the zona incerta may play a crucial role in relaying trigeminal information.

Genera of the North American Corticiaceae sensu lato

The significance of E.A. Burt's “The Thelephoraceae of North America,” published from 1914 to 1926, to the current concept of the Corticiaceae is discussed. The numbers of species of the Corticiaceae reported from various regions of the World are compared. The principal portion of the text is a synopsis of the 165 genera comprising the Corticiaceae s.l. of Canada and the United States of America. The distinctive features for each genus are itemized. Comments are included to aid in the identification of specimens. For genera with a limited number of species, the diagnostic features are given for each species. For larger genera, references are given to keys which include all or most North American species. The generic name Leifia is proposed as a nom. nov. for Granulocystis Hjortstam.

Genera of the North American Corticiaceae Sensu Lato

The significance of E.A. Burt's “The Thelephoraceae of North America,” published from 1914 to 1926, to the current concept of the Corticiaceae is discussed. The numbers of species of the Corticiaceae reported from various regions of the World are compared. The principal portion of the text is a synopsis of the 165 genera comprising the Corticiaceae s.l. of Canada and the United States of America. The distinctive features for each genus are itemized. Comments are included to aid in the identification of specimens. For genera with a limited number of species, the diagnostic features are given for each species. For larger genera, references are given to keys which include all or most North American species. The generic name Leifia is proposed as a nom. nov. for Granulocystis Hjortstam.

The determinants of investment in new technology: An examination of alternative hypotheses

This article evaluates and finds support for the hypothesis that innovative activity undertaken by firms, as measured by the level of investments in new technology, is a positive function of micro-market pressures that they face from potential competitors. The empirical context studies is a cross-sectional sample of 40 firms that make up the principal portion of the local operating sector of the U.S. telecommunications industry. Firm size and potential market power are both found to be insignificant but negative, thus not validating two hypotheses much researched in the literature that innovative activity is a positive function of firm size and potential market power. Demand-growth and imitation effects are also controlled in the model and are found positively to induce investment in new technology.

Cognitive and Behavioral Components of Expertise in Teaching Physical Education

The purpose of this paper is to synthesize research on teaching expertise from physical education and other fields, although this is not an exhaustive review of the literature. After an introductory section about expertise in general and teaching expertise in particular, two examples of expertiserelated topics in physical education are discussed (the importance of personal performance skills and the importance of observational skills). The principal portion of the paper presents major findings about teaching expertise. Finally, methodological problems in undertaking research on teaching expertise are explained.

Serials Automation At UCLA

ORION is UCLA's online integrated processing and public access system. The system and its development are described briefly. The principal portion of the discussion centers round the serials component which includes ordering, check-in. claiming, binding, payment processing and fund accounting. UCLA's serials data conversion activities are also summarized.

Suburbs for a Labor Elite

Suburbs for a Labor Elite

Mechanical properties of developing swine myocardium

1. 1. Mechanical responses of myocardium from 16 piglets were studied from 18hr to 12 days after birth. Tension, time and velocity parameters of contraction and relaxation were determined for every contraction cycle. 2. 2. Increasing the frequency of stimulation in step-changes induced negative inotropy in some muscles regardless of age. 3. 3. Doubling extracellular calcium ion concentration induced a positive force-frequency response in all muscles. 4. 4. Epinephrine increased tension and velocities without affecting contraction time. 5. 5. The ultrastructure was immature even on the 12th postnatal day. 6. 6. We concluded that in newborn piglet hearts, the mechanisms for calcium delivery are not fully developed. Thus, the heart undergoes a transient phase during which at least a principal portion of calcium for the myofibers is supplied by the extracellular fluid. 7. 7. While receptors for catecholamines are present, the time course for their response is immature.