bluuebunny/crossref_metadata_2025 huggingface dataset:
Everything you always wanted to know about sex and dopamine, but were afraid to ask
Authors: Müller Christian P.
Published: December 2019

Behavioral neuroscience has taken a long time to finally recognize that the largely distinct behavioral repertoires of males and females may arise from differences in brain function. This may in particular apply for the neurochemistry of the dopamine systems and their roles in the organization of emotion, learning, and reinforcement in health and in pathological conditions. The current Editorial highlights a study by Egenrieder and colleagues published in the current issue of the Journal of Neurochemistry, in which the authors have analyzed extracellular dopamine neurochemistry from females and males in a meta‐analysis. Largely surprising, they report that after detailed control of methodological differences between studies, no major differences in basal or drug‐induced extracellular dopamine activity emerged between sexes in rodents. The locally dissociating effects of ovariectomy in females reported in the Egenrieder et al. study, may furthermore suggest that there may be different sex effects in the distinct dopaminergic projections of the mesolimbic and nigrostriatal dopamine system. However, this may only be the beginning of a system's analysis of dopaminergic sex differences that calls for further meta‐analyses of the existing studies.

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Role of fasciae around the median nerve in pathogenesis of carpal tunnel syndrome: microscopic and ultrasound study
Authors: Stecco Carla , Giordani Federico , Fan Chenglei , Biz Carlo , Pirri Carmelo , Frigo Anna Chiara , Fede Caterina , Macchi Veronica , Masiero Stefano , De Caro Raffaele
Published: December 2019

This study investigated the connections between the median nerve paraneural sheath and myofascial structures near it, from both macroscopic and microscopic points of view. Four samples of median nerve and surrounding tissues were excised from nine non‐embalmed upper limbs for microscopic analysis. Ultrasound images were analysed in 21 healthy subjects and 16 carpal tunnel syndrome patients to evaluate median nerve transversal displacement during finger motion at carpal tunnel and forearm levels. An anatomical continuity between epimysium and paraneural sheath and a reduction of paraneural fat tissue from proximal to distal was found in all samples. Median nerve displacements at both levels were significantly reduced in carpal tunnel syndrome subjects (P < 0.001). It was observed that the median nerve is not an isolated structure but is entirely connected to myofascial structures. Therefore, unbalanced tension of epimysial fasciae can affect the paraneural sheath, limiting nerve displacement, and consequently this must be included in carpal tunnel syndrome pathogenesis.
Comparative skeletal anatomy of neonatal ursids and the extreme altriciality of the giant panda
Authors: Li Peishu , Smith Kathleen K.
Published: December 2019

Mammalian neonates are born at a wide range of maturity levels. Altricial newborns are born with limited sensory agency and require extensive parental care. In contrast, precocial neonates are relatively mature physically and often capable of independent function shortly after birth. In extant mammals, placental newborns vary from altricial to precocial, while marsupials and monotremes are all extremely altricial at birth. Bears (family Ursidae) have one of the lowest neonatal−maternal mass ratios in placental mammals, and are thought to also have the most altricial placental newborns. In particular, giant pandas (Ailuropoda melanoleuca) are thought to be exceptionally altricial at birth, and possibly marsupial‐like. Here we used micro‐computer (micro‐computed) tomography scanning to visualize the skeletal anatomy of ursid neonates and compare their skeletal maturity with the neonates of other caniform outgroups. Specifically, we asked whether ursid neonates have exceptionally altricial skeletons at birth compared with other caniform neonates. We found that most bear neonates are similar to outgroup neonates in levels of skeletal ossification, with little variation in degree of ossification between ursine bears neonates (i.e. bears of the subfamily Ursinae). Perinatal giant pandas, however, have skeletal maturity levels most similar to a 42−45‐day‐old beagle fetus (~70% of total beagle gestation period). No bear exhibits the skeletal heterochronies seen in marsupial development. With regards to skeletal development, ursine bears are not exceptionally altricial relative to other caniform outgroups, but characterized largely by the drastic difference between newborn and adult body sizes. A review on the existing hypotheses for ursids’ unique reproductive strategy suggests that the extremely small neonatal−maternal mass ratio of ursids may be related to the recent evolution of large adult body size, while life history characteristics retained an ancestral condition. A relatively short post‐implantation gestation time may be the proximal mechanism behind the giant panda neonates’ small size relative to maternal size and altricial skeletal development at birth.
Histological examination of skin tissue in the porcine animal model after simultaneous and consecutive application of monopolar radiofrequency and targeted pressure energy
Authors: Kinney Brian M. , Kanakov Dian , Yonkova Penka
Published: December 2019

Background

The cosmetic appearance of skin is substantially influenced by the organization of connective fibers and underlying subcutaneous tissue. It has been previously documented that radiofrequency and pressure energies alone are able to improve skin appearance; however, detailed histological evaluation should be done to determine their synergistic effect.

Aims

This histological study investigates the difference between simultaneous and consecutive application of monopolar radiofrequency with targeted pressure energy on porcine skin.

Methods

In a total of four weekly abdominal treatments, simultaneous emission of the energies was applied to two pigs (12 minutes per session); additionally, two pigs were treated consecutively (12 + 12 minutes per session). The 5th pig served as a control subject. Biopsies were obtained at baseline, after the 4th treatment, and at 1‐month follow‐up. Primary outcomes were to document changes of dermal and hypodermal tissues.

Results

In the treated subjects, the amount of collagen and elastin fibers increased significantly (P < .001). At follow‐up, simultaneous application showed a significantly higher increase in collagen and elastin fibers (by 59% and 64%, respectively), when compared to consecutive. Thickness of the dermis increased more in the pigs treated simultaneously (+848.8 µm/50.17%; P < .001). Treated tissue also showed the upper part of dermis to be rich in blood vessels and better organized interlobular septa in hypodermis. No significant change was observed in the control subject.

Conclusion

Simultaneous application produces significantly more profound changes, when compared to consecutive treatment. Further research is needed but our findings represent a new potential treatment of various skin conditions like cellulite or laxity.
Social support as predictor of anxiety and depression in cancer caregivers six months after cancer diagnosis: A longitudinal study
Authors: García‐Torres Francisco , Jacek Jabłoński Marcin , Gómez Solís Ángel , Moriana Juan Antonio , Jaén‐Moreno Maria José , Moreno‐Díaz Maria José , Aranda Enrique
Published: December 2019

Aims and Objectives

To establish the predictive utility of specific social support domains for emotional well‐being in cancer caregivers, six months after their partner's cancer diagnosis.

Background

In cancer caregivers, social support has been consistently related to anxiety and depression. There is little information, however, about the predictive utility of specific social support domains for psychological well‐being in the first six months after a partner's cancer diagnosis.

Design

Longitudinal research study.

Methods

Sixty‐seven caregivers of recently diagnosed cancer patients were recruited from the Reina Sofia University Hospital in Cordoba (Spain). Participants completed a set of questionnaires including the Berlin Social Support Scale (BSSS), the Hospital Anxiety and Depression Scale (HADS) and a socio‐demographic questionnaire. Data were collected at two time points: T1 (30–45 days after diagnosis) and T2 (180–200 days after). TRIPOD checklist was used.

Results

Most of the caregivers were female (65%) and the partner of the patient (58%), with an average age of 51.63 years (SD = 13.25). Statistical differences were observed between the two assessment points for the social support domains of perceived emotional support, satisfaction with support and protective buffering. Logistic regression analysis showed that less physical and sports activity, more support seeking and less informational support received at T1 predicted anxiety at T2, while less perceived available support predicted depression.

Conclusions

Accurate information and support from other members of the community and the promotion of physical and sports routines for cancer caregivers may help to alleviate symptoms of anxiety and depression in the first months after a partner's cancer diagnosis.

Relevance to clinical practice

Clinicians must pay attention to the social support needs and physical activity of caregivers in the first days after diagnosis, in order to prevent anxiety and depression.
Racial/Ethnic Differences in the Association Between Family Structure and Children's Education
Authors: Cross Christina J.
Published: December 2019

Objective

This study tested two hypotheses that have been posited to account for racial/ethnic differences in the association between family structure and children's education.

Background

Research has shown that children raised by both biological parents fare better academically than children raised in any other family structure. However, there has been little research to explain an important finding: living apart from a biological parent is less negatively consequential for racial/ethnic minority children than white children. Scholars have speculated that group differences in exposure to socioeconomic stress and embeddedness in extended family networks explain this finding.

Method

This study used nationally representative, longitudinal data from the Panel Study of Income Dynamics (n = 2,589). It employed logistic regression analysis and decomposition techniques to assess whether racial/ethnic differences in these two mechanisms explained the differential association between family structure and children's on‐time high school completion and college enrollment for white, black, and Hispanic children.

Results

The results indicate that socioeconomic stress and extended family embeddedness attenuate the effect of family structure on these two measures of children's education, although the former to a much greater extent. The differences in socioeconomic resources accounted for up to nearly 50% of the gap in these outcomes, and extended family embeddedness explained roughly 15% to 20%.

Conclusion

Findings lend support for the socioeconomic stress hypothesis, which posits that the negative effect of parental absence from the home may be less independently impactful for racial/ethnic groups already facing many socioeconomic disadvantages.
RNAi suppression of CYP82D P450 hydroxylase, an enzyme involved in gossypol biosynthesis, enhances resistance to Fusarium wilt in cotton
Authors: Wagner Tanya A. , Cai Yingfan , Bell Alois A. , Puckhaber Lorraine S. , Magill Clint , Duke Sara E. , Liu Jinggao
Published: December 2019

Cotton plants produce two classes of terpenoid defence compounds against pathogens and other pests. Both classes are derived from a common sesquiterpenoid precursor, δ‐cadinen‐2‐one, which enters either the gossypol pathway or the lacinilene pathway. Blocking the gossypol pathway by RNAi suppression of the early pathway biosynthetic enzyme CYP82D hydroxylase resulted in enhanced resistance to the Fusarium wilt pathogen. Analyses of root terpenoids revealed no overall increases in the products of the gossypol pathway in the roots infected by the wilt pathogen. However, the lacinilene pathway was elicited by the pathogen and the lacinilene levels were 19‐fold higher in the RNAi plants than in wild‐type plants. In the pathogen inoculated RNAi 73R plants, the concentrations of DHC and HMC were 231 μg and 886 μg/g dry roots, respectively, which may have contributed to the inhibition of fungal invasion. In comparison, the concentrations of DHC and HMC in the pathogen inoculated control wild‐type 73W plants were only 0.7 μg and 58 μg/g dry roots, respectively. Fungitoxicity testing showed that DHC at 100 μg/ml inhibited growth of the Fusarium wilt pathogen by >93%. Treatment with the phytohormone jasmonic acid failed to elicit production of lacinilene pathway terpenoids in roots of either RNAi plants or their wild‐type sibling lines, but increased production of gossypol pathway terpenoids with concentrations in RNAi plants 80%–97% less than those in wild‐type plants. This indicates that induction of the lacinilene pathway is not directly mediated by jasmonic acid signalling and requires other signalling to activate the pathway. These results illustrate possible mechanisms of wilt disease resistance in cotton and provide a new approach to increase host resistance by manipulating these two major cotton chemical defence pathways.
Two reproductive traits show contrasting genetic architectures in Plantago lanceolata
Authors: Marshall Matthew M. , Remington David L. , Lacey Elizabeth P.
Published: December 2019

In many species, temperature‐sensitive phenotypic plasticity (i.e., an individual's phenotypic response to temperature) displays a positive correlation with latitude, a pattern presumed to reflect local adaptation. This geographical pattern raises two general questions: (a) Do a few large‐effect genes contribute to latitudinal variation in a trait? (b) Is the thermal plasticity of different traits regulated pleiotropically? To address the questions, we crossed individuals of Plantago lanceolata derived from northern and southern European populations. Individuals naturally exhibited high and low thermal plasticity in floral reflectance and flowering time. We grew parents and offspring in controlled cool‐ and warm‐temperature environments, mimicking what plants would encounter in nature. We obtained genetic markers via genotype‐by‐sequencing, produced the first recombination map for this ecologically important nonmodel species, and performed quantitative trait locus (QTL) mapping of thermal plasticity and single‐environment values for both traits. We identified a large‐effect QTL that largely explained the reflectance plasticity differences between northern and southern populations. We identified multiple smaller‐effect QTLs affecting aspects of flowering time, one of which affected flowering time plasticity. The results indicate that the genetic architecture of thermal plasticity in flowering is more complex than for reflectance. One flowering time QTL showed strong cytonuclear interactions under cool temperatures. Reflectance and flowering plasticity QTLs did not colocalize, suggesting little pleiotropic genetic control and freedom for independent trait evolution. Such genetic information about the architecture of plasticity is environmentally important because it informs us about the potential for plasticity to offset negative effects of climate change.
Increased diversification rates are coupled with higher rates of climate space exploration in Australian Acacia (Caesalpinioideae)
Authors: Renner Matt A. M. , Foster Charles S. P. , Miller Joseph T. , Murphy Daniel J.
Published: December 2019

Australia is an excellent setting to explore relationships between climate change and diversification dynamics. Aridification since the Eocene has resulted in spectacular radiations within one or more Australian biomes. Acacia is the largest plant genus on the Australian continent, with around 1000 species, and is present in all biomes. We investigated the macroevolutionary dynamics of Acacia within climate space.

We analysed phylogenetic and climatic data for 503 Acacia species to estimate a time‐calibrated phylogeny and central climatic tendencies for BioClim layers from 132 000 herbarium specimens. Diversification rate heterogeneity and rates of climate space exploration were tested.

We inferred two diversification rate increases, both associated with significantly higher rates of climate space exploration. Observed spikes in climate disparity within the Pleistocene correspond with onset of Pleistocene glacial–interglacial cycling.

Positive time dependency in environmental disparity applies in the basal grade of Acacia, though climate space exploration rates were lower. Incongruence between rates of climate space exploration and disparity suggests different Acacia lineages have experienced different macroevolutionary processes. The second diversification rate increase is associated with a south‐east Australian mesic lineage, suggesting adaptations to progressively aridifying environments and ability to transition into mesic environments contributed to Acacia's dominance across Australia.
The origin of the turtle body plan: evidence from fossils and embryos
Authors: Schoch Rainer R. , Sues Hans‐Dieter
Published: December 2019

The origin of the unique body plan of turtles has long been one of the most intriguing mysteries in evolutionary morphology. Discoveries of several new stem‐turtles, together with insights from recent studies on the development of the shell in extant turtles, have provided crucial new information concerning this subject. It is now possible to develop a comprehensive scenario for the sequence of evolutionary changes leading to the formation of the turtle body plan within a phylogenetic framework and evaluate it in light of the ontogenetic development of the shell in extant turtles. The fossil record demonstrates that the evolution of the turtle shell took place over millions of years and involved a number of steps.
Paying out one versus paying out all trials and the decrease in behavioral and brain activity in the Balloon Analogue Risk Task
Authors: Xu Sihua , Wang Hua , Wang Cencen
Published: December 2019

Both pay out for all the trials (pay‐all) and pay out for only one randomly selected trial (pay‐one), are widely used in economics experiments to elicit choices from study participants. However, whether pay‐all and pay‐one payments modulate risk‐taking and decision‐making in the same manner remains controversial. In the present study, we used event‐related potentials (ERPs) with the Balloon Analogue Risk Task (BART) to investigate the effects of the pay‐all and pay‐one payments on dynamic sequential decision‐making behavior under uncertainty and brain activity. Behavioral data showed an increased uncertainty aversion, especially after negative feedback (balloon explosion) during the BART in the pay‐all condition, as compared to those in the pay‐one condition. The ERP data demonstrated a larger feedback‐related negativity (FRN) in response to the balloons that exploded during decision‐making in the pay‐all condition, as compared to those in the pay‐one condition. In addition, in the pay‐all condition, the FRN amplitude elicited by the explosion of the balloon correlated with the future decision‐making behavior, although this correlation was not observed in the pay‐one condition. In contrast, the P300 component was unresponsive to payment method manipulation. These findings demonstrate the differential effects of the pay‐all versus the pay‐one payments on decision‐making behavior under uncertainty and brain activity, suggesting that the payment method plays an important role in dynamic decision‐making studies.
Management of intraoral bleeding in patients with Waldenström macroglobulinemia: A protocol proposal
Authors: Ueda Sei , Ishii Kou , Fujii Hitoshi , Mizutani Konosuke , Komaki Kanji , Nagao Toru
Published: December 2019

Aim

Waldenström macroglobulinemia is a type of non‐Hodgkin lymphoma with poor prognosis observed in patients with hyperviscosity syndrome because of its tendency for fatal symptoms. This study investigated the risk of intraoral bleeding in patients with Waldenström macroglobulinemia based on hyperviscosity syndrome stage and oral health status, and described potential strategies for managing intraoral bleeding.

Methods and results

Between April 2012 and March 2017, seven patients with Waldenström macroglobulinemia underwent dental procedures or tooth extraction. Patient records were retrospectively reviewed to obtain data of symptoms, clinical and radiographic findings, treatment details, pretreatment hematological findings, hyperviscosity syndrome status, perioperative method for local haemostasis, postoperative bleeding, and prognosis.

The mean patient age was 71.2 years, and the male‐to‐female ratio was 6:1. Treatment modalities for oral management comprised tooth extraction, scaling, and oral cavity cleaning. Three patients were admitted for hyperviscosity syndrome; one of the patients exhibited postoperative bleeding because of poor oral hygiene, whereas the two other patients with good oral hygiene did not experience intraoral bleeding regardless of the presence of hyperviscosity syndrome.

Conclusion

We recommended that the risk of oral bleeding in patients with Waldenstrom's macroglobulinemia should be assessed for oral health in addition to the stage of hyperviscosity syndrome.
Using Evidence to Drive Impact: Developing the FP Goals Impact Matrix
Authors: Weinberger Michelle , Williamson Jessica , Stover John , Sonneveldt Emily
Published: December 2019

When designing a family planning (FP) strategy, decision‐makers can choose from a wide range of interventions designed to expand access to and develop demand for FP. However, not all interventions will have the same impact on increasing modern contraceptive prevalence (mCP). Understanding the existing evidence is critical to planning successful and cost‐effective programs. The Impact Matrix is the first comprehensive summary of the impact of a full range of FP interventions on increasing mCP using a single comparable metric. It was developed through an extensive literature review with input from the wider FP community, and includes 138 impact factors highlighting the range of effectiveness observed across categories and subcategories of FP interventions. The Impact Matrix is central to the FP Goals model, used to project scenarios of mCP growth that help decision‐makers set realistic goals and prioritize investments. Development of the Impact Matrix, evidence gaps identified, and the contribution to FP Goals are discussed.
Evaluation of the efficacy of triamcinolone acetonide in the treatment of keloids by high‐frequency ultrasound
Authors: Cai Lei , Hu Murong , Lin Lele , Zheng Tianyin , Liu Jingjing , Li Zhiming
Published: December 2019

Background

Intralesional injection of triamcinolone acetonide is an effective method for treating keloids. It still lacks effective and objective evaluation methods. This study aimed to observe the efficacy of intralesional triamcinolone acetonide injections for the treatment of keloids and to explore the role of high‐frequency ultrasound in the monitoring and evaluation of keloids therapy.

Methods

Fifty‐one patients with keloids were treated with triamcinolone acetonide, once a week for 4 weeks. Lesions were detected, recorded, and evaluated using digital photography and high‐frequency ultrasound before and after treatment.

Results

High‐frequency ultrasound showed the depth of drug injection. After the last treatment, an average decrease in dermal tissue layer thickness of 39.0% is compared with before treatment. In addition, there are significant differences in the effectiveness of clinical assessments and ultrasound assessments of keloids with or without subjective symptoms.

Conclusion

The observed results confirmed that intralesional injections of triamcinolone acetonide can effectively treat keloids. High‐frequency ultrasound can be used as a therapeutic monitoring and therapeutic evaluation tool for intralesional injections of triamcinolone acetonide.
Implicit Counterpoint in Gjerdingen's Schemata
Authors: Rabinovitch Gilad
Published: December 2019

Robert Gjerdingen has claimed that schema finding diverges from contrapuntal pitch reduction, Schenkerian or otherwise. Commentators have criticized his approach (see the reviews by Joel Lester in Journal of Music Theory [1990] and Kofi Agawu in Music Theory Spectrum [1991])
and have discussed intersections between schemata and contrapuntal reduction (see the articles by Folker Froebe and Oliver Schwab-Felisch in Music Theory and Analysis [2014] and by Stefan Rohringer in Zeitschrift der Gesellschaft für Musiktheorie [2015]). Here I address
this conundrum from a different angle: I propose that schema analysis may be approximated by two heuristics, which are closely related to the issue identified in Fred Lerdahl and Ray Jackendoff's A Generative Theory of Tonal Music (1983) as finding the head of a time span. By
giving the highest priority to tritone resolutions within a metric segment and otherwise realigning consonances with strong beats by removing dissonances, it is possible to approximate the reductive workings of schema analysis. This is demonstrated through a preliminary sample of two hundred
tacit reductive decisions from Gjerdingen's Music in the Galant Style. I suggest the possibility that Gjerdingen's locally top-down search for complete patterns interacts with a more bottom-up, implicit reductive process, regardless of the identity of the emergent schema. I also discuss
some of the potential implications of the heuristics for theory and analysis as well as for interdisciplinary work on schema finding.
"Nécessité d'une orientation esthétique": Techniques of Development in the Music of Boulez
Authors: Losada Catherine
Published: December 2019

The latter part of the 1950s saw a major change in Boulez's compositional approach: Instead of creating extensive pre-compositional sketches, he increasingly reused previously composed materials as the basis for new works. The shifting aesthetics that characterized this period had a
significant influence on Boulez. His works from the late 1950s explore the ideas of mobility embedded in the open work. Balancing the concept of mobility with the ideals of control that form the basis of his compositional ideology led to an economy of means and an associated emphasis on the
concept of development in his compositional process. Both facilitated the creation of new works from a more limited array of base materials.
 Tracing the concept of development in a sample of Boulez's sketches and works from the late 1950s through the 1960s, this essay presents a
preliminary typology of recurring pitch and temporal developmental techniques. By taking a bird's-eye view, I add an additional level of interpretation, emphasizing their formal function, association with aspects of middleground structure and studying their implications in terms of perception.
In this way, I present a new perspective on the association between these techniques and the practice of derivation from a limited amount of material that characterizes these works.
Matter over Mind in The Secular Commedia
Authors: Goehring Edmund J.
Published: December 2019

The first in a set of review articles treating Wye Allanbrook's posthumously published Secular Commedia (University of California Press, 2014). The reviews originated as a panel discussion organized by Edmund J. Goehring at the Mozart Society of America's 2018 meeting at the
University of Western Ontario.
Influence of Metal Electrodes on the Charge Extraction of Inverted Perovskite Solar Cells
Authors: Gong Jiawei , Krishnan Sumathy
Published: December 2019

A perovskite solar cell in the inverted configuration was modeled and simulated to investigate the impact of the cathode work function on the cell performance. The model utilized the drift-diffusion current equations, coupled with Poisson’s equation and continuity equations to determine the J-V characteristics, the band diagram, and the external quantum efficiencies. It was found the power conversion efficiency (PCE) tended to decrease with the increasing work functions of the metal cathode. The device using low work function metal Ca delivered the best PCE of 16.7%, whereas the one with high work function Au possessed the lowest PCE of 0.3%. These results were in a close agreement with experiments in literature. Photovoltaic parameters (FF, Jsc, and Voc) showed the same tendency and were responsible for the PCE. The band diagram revealed the formation of Schottky barrier was the main reason for the reduction in Voc, and the external quantum efficiency spectrum showed the adverse effect of the Schottky barrier on the charge extraction.
Comparative Studies on the Effect of Selected Iron-Based Additives on Anaerobic Digestion of Okra Waste
Authors: Ugwu Samson N. , Enweremadu Christopher C.
Published: December 2019

Biogas production is an anaerobic waste-to-energy technology, involving waste degradation and stabilization. The sustainable, cheap and clean nature of biogas has led to the unprecedented rise in its use as an alternative energy source. Due to the increased interests, availability of conventional biodegradable organics has shrunk enormously over the years, necessitating the aggressive search for novel energy crops and substrate enhancement options. These novel options ensure feedstock security, optimize conventional biomass feedstocks, improve feedstock degradability and increase in biogas yield. Low biodegradability of most lignocellulosic wastes like okra waste, limits their use as a viable substrate in the anaerobic digestion process. Over the years, several elements, compounds and nanoparticles have been applied to anaerobic digestion systems as supplementary nutrients with a view to enhancing substrate degradation. Such supplements like iron-based additives have gained prominence in anaerobic digestion processes of wastes, owing to their electron donation abilities, promotion of solubilization, hydrolysis, acidification, and hydrogenotrophic methanogenesis. In a bid to enhance substrate degradation, reduce inhibitions, increase both biogas yield and methane content, a comparative study on the influence of four different iron-based additives (nanoscale zero-valent iron (nZVI), Polypyrrole-magnetic nanocomposite (Ppy-Fe3O4), Iron powder (Fe) and Hematite (Fe2O3)) on the entire anaerobic digestion of okra waste was done. Previously determined optimum doses, 20 mg, 20 mg, 750 mg, 750 mg and 0 respectively for nZVI, Ppy-Fe3O4, Fe, Fe2O3 and control were added to the bioreactors containing okra wastes in a 500 mL biomethane potential bioreactors under mesophilic temperature (37°C) for 20 days.

The cumulative volumes of the biogas from different reactors were recorded and analyzed. The morphological deformation, structures and analysis of the undigested substrate, digestates of substrate supplemented with iron-based additives and the control were evaluated with scanning electron microscopy (SEM). Artificial neural network (ANN) model and the modified Gompertz model were validated with the experimental data. The ANN model showed better goodness of fit and was better correlated with the experimental data. Experimental data were subjected to analysis of variance at a 95% confidence level. Results showed that Ppy-Fe3O4 additives better enhanced both biogas yield and methane contents significantly when compared to the control. It was also observed that all iron-additive supplemented processes were more degraded when compared with the control.
Performance Characteristics of Philippine Hydrous Ethanol-Gasoline Blends: Preliminary Findings
Authors: Yu John Luis , Quiros Edwin N.
Published: December 2019

To reduce dependence on imported fossil fuels and develop indigenous biofuels, the Philippines enacted the Biofuels Act of 2006 which currently mandates a 10% by volume blend of 99.6% anhydrous bio-ethanol for commercially sold Unleaded and Premium gasolines. To urge a regulation review of the anhydrous requirement and examine the suitability for automotive use of hydrous bioethanol (HBE) blends, preliminary engine dynamometer tests at 1400–4400 rpm were conducted to measure specific fuel consumption (SFC) and power. In this study, HBE (95 % ethanol and 5% water by volume) produced from sweet sorghum using a locally-developed process, was blended volumetrically with three base gasoline fuels — Neat, Unleaded, and Premium. The four HBE blends tested were 10% and 20% with Neat gasoline, 20% with Unleaded gasoline, and 20% with Premium gasoline.

For blends with Neat gasoline, the SFC of the 10%HBE blend was comparable with to slightly higher than Neat gasoline. The SFC of the 20%HBE blend was comparable with Neat gasoline up to 2800 rpm and lower beyond this speed thus being better overall than the 10%HBE blend. Compared to their respective commercial base fuels, the HBE-Unleaded blend showed lower SFC while the HBE-Premium blend yielded slightly higher SFC over most of the engine speed range. Between commercial fuel blends, the HBE-Unleaded blend gave better SFC than the HBE-Premium blend. Power was practically similar for the fuels tested. No engine operational problems and fuel blend phase separation were encountered during the tests. This preliminary study indicated the suitability of and possible optimum hydrous bio-ethanol blends for automotive use under Philippine conditions.
Characterization of Particle and Heat Losses From Falling Particle Receivers
Authors: Ho Clifford K. , Kinahan Sean , Ortega Jesus D. , Vorobieff Peter , Mammoli Andrea , Martins Vanderlei
Published: December 2019

Camera-based imaging methods were evaluated to quantify both particle and convective heat losses from the aperture of a high-temperature particle receiver. A bench-scale model of a field-tested on-sun particle receiver was built, and particle velocities and temperatures were recorded using the small-scale model. Particles heated to over 700 °C in a furnace were released from a slot aperture and allowed to fall through a region that was imaged by the cameras. Particle-image, particle-tracking, and image-correlation velocimetry methods were compared against one another to determine the best method to obtain particle velocities. A high-speed infrared camera was used to evaluate particle temperatures, and a model was developed to determine particle and convective heat losses. In addition, particle sampling instruments were deployed during on-sun field tests of the particle receiver to determine if small particles were being generated that can pose an inhalation hazard. Results showed that while there were some recordable emissions during the tests, the measured particle concentrations were much lower than the acceptable health standard of 15 mg/m3. Additional bench-scale tests were performed to quantify the formation of particles during continuous shaking and dropping of the particles. Continuous formation of small particles in two size ranges (< ∼1 microns and between ∼8–10 microns) were observed due to de-agglomeration and mechanical fracturing, respectively, during particle collisions.
Robust Control of Hydrogen Flow for an Automotive Fuel Cell System via Model Reference Adaptive Control
Authors: Hwang Janghwan , Yu Sangseok
Published: December 2019

Efficient hydrogen flow control is of great importance to ensure the reliable operation of an automotive fuel cell system because it is closely associated with the safety and the economic efficiency. In this study, an effective hydrogen flow control algorithm for hydrogen excess ratio control is addressed by pointing out the recovery speed and overshoot response. Unlike previous studies on the hydrogen management systems of an automotive fuel cell, this study presents an analytic hydrogen tank model which can present the characteristics of the discharge and charge of hydrogen from a type 4 hydrogen tank. To this end, a mode reference adaptive control (MRAC) based on proportional-integral (PI) control is introduced, to ensure robust hydrogen flow during the dynamic operation of fuel cell system. The MRAC was compared with the nominal PI control and PWM control in the hydrogen management system of an automotive fuel cell operating within normal conditions, under steady-state responses and transient. Based on these result, it can further demonstrate that the MRAC algorithm shows better recovery speed and tracking performance than the nominal PI, and PWM control algorithm with respect to the transient behaviors.
Optimization of Storage Bin Geometry for High Temperature Particle-Based CSP Systems
Authors: Sment Jeremy , Albrecht Kevin , Christian Joshua , Ho Clifford K.
Published: December 2019

Solid particle receivers provide an opportunity to run concentrating solar tower receivers at higher temperatures and increased overall system efficiencies. The design of the bins used for storing and managing the flow of particles creates engineering challenges in minimizing thermomechanical stress and heat loss. An optimization study of mechanical stress and heat loss was performed at the National Solar Thermal Test Facility at Sandia National Laboratories to determine the geometry of the hot particle storage hopper for a 1 MWt pilot plant facility. Modeling of heat loss was performed on hopper designs with a range of geometric parameters with the goal of providing uniform mass flow of bulk solids with no clogging, minimizing heat loss, and reducing thermomechanical stresses. The heat loss calculation included an analysis of the particle temperatures using a thermal resistance network that included the insulation and hopper. A plot of the total heat loss as a function of geometry and required thicknesses to accommodate thermomechanical stresses revealed suitable designs. In addition to the geometries related to flow type and mechanical stress, this study characterized flow related properties of CARBO HSP 40/70 and Accucast ID50-K in contact with refractory insulation. This insulation internally lines the hopper to prevent heat loss and allow for low cost structural materials to be used for bin construction. The wall friction angle, effective angle of friction, and cohesive strength of the bulk solid were variables that were determined from empirical analysis of the particles at temperatures up to 600°C.
Comparison and Implementation of Thermally Massive Wall and Roof Models for Use in Simplified Building Energy Models
Authors: Fernandez Christopher , Jeter Sheldon
Published: December 2019

Although contemporary and complex building energy models such as EnergyPlus are highly advanced and predictive, a simplified building energy model has many advantages and applications. Chief among the advantages are adaptability to the measured response of a building and conciseness in computer implementation. Important applications will include automated fault detection. One of the most important aspects of a successful building energy model is the ability to accurately account for the heat capacity of the structure, especially the envelope. As part of the development of a simplified physics-based building energy model, a variety of roof and wall models were considered. Three different generic models were considered for opaque walls and roofs (1) an analytical model with closed-form solution, (2) a time-series solution using the ASHRAE transfer function method, and (3) a lumped capacity model with various numbers of capacitive nodes. This paper will describe an investigation of various simplified models for the transient conduction through building walls. Specifically, how different kinds of wall constructions and materials can change when the conduction load passes through the wall and when it impacts the HVAC system. Understanding how the physics of dynamic envelope loading can change how much energy a building uses for heating or cooling and when room conditioning loads occur is vital for energy savings and proper modeling.
Effect of Quartz Aperture Covers on the Fluid Dynamics and Thermal Efficiency of Falling Particle Receivers
Authors: Yue Lindsey , Mills Brantley , Ho Clifford K.
Published: December 2019

Falling particle receivers are an emerging technology for use in concentrating solar power systems. In this work, quartz tubes cut in half to form tube shells (referred to as quartz half-shells) are investigated for use as a full or partial aperture cover to reduce radiative and advective losses from the receiver. A receiver subdomain and surrounding air volume are modeled using ANSYS® Fluent®. The model is used to simulate fluid dynamics and heat transfer for the following cases: (1) open aperture, (2) aperture fully covered by quartz half-shells, and (3) aperture partially covered by quartz half-shells. We compare the percentage of total incident solar power lost due to conduction through the receiver walls, advective losses through the aperture, and radiation exiting out of the aperture. Contrary to expected outcomes, simulation results using the simplified receiver subdomain show that quartz aperture covers can increase radiative losses and, in the partially covered case, also increase advective losses. These increased heat losses are driven by elevated quartz half-shell temperatures and have the potential to be mitigated by active cooling and/or material selection.
Optical Performance Modeling and Analysis of a Tensile Ganged Heliostat Concept
Authors: Yellowhair Julius , Andraka Charles E. , Armijo Kenneth M. , Ortega Jesus D. , Clair Jim
Published: December 2019

Designs of conventional heliostats have been varied to reduce cost, improve optical performance or both. In one case, reflective mirror area on heliostats has been increased with the goal of reducing the number of pedestals and drives and consequently reducing the cost on those components. The larger reflective areas, however, increase torques due to larger mirror weights and wind loads. Higher cost heavy-duty motors and drives must be used, which negatively impact any economic gains. To improve on optical performance, the opposite may be true where the mirror reflective areas are reduced for better control of the heliostat pointing and tracking. For smaller heliostats, gravity and wind loads are reduced, but many more heliostats must be added to provide sufficient solar flux to the receiver. For conventional heliostats, there seems to be no clear cost advantage of one heliostat design over other designs.

The advantage of ganged heliostats is the pedestal and tracking motors are shared between multiple heliostats, thus can significantly reduce the cost on those components. In this paper, a new concept of cable-suspended tensile ganged heliostats is introduced, preliminary analysis is performed for optical performance and incorporated into a 10 MW conceptual power tower plant where it was compared to the performance of a baseline plant with a conventional radially staggered heliostat field. The baseline plant uses conventional heliostats and the layout optimized in System Advisor Model (SAM) tool. The ganged heliostats are suspended on two guide cables. The cables are attached to rotations arms which are anchored to end posts. The layout was optimized offline and then transferred to SAM for performance evaluation.

In the initial modeling of the tensile ganged heliostats for a 10 MW power tower plant, equal heliostat spacing along the guide cables was assumed, which as suspected leads to high shading and blocking losses. The goal was then to optimize the heliostat spacing such that annual shading and blocking losses are minimized. After adjusting the spacing on tensile ganged heliostats for minimal blocking losses, the annual block/shading efficiency was greater than 90% and annual optical efficiency of the field became comparable to the conventional field at slightly above 60%.
On-Sun Tracking Evaluation of a Small-Scale Tensile Ganged Heliostat Prototype
Authors: Yellowhair Julius , Armijo Kenneth M. , Ortega Jesus D. , Clair Jim
Published: December 2019

Various ganged heliostat concepts have been proposed in the past. The attractive aspect of ganged heliostat concepts is multiple heliostats are grouped so that pedestals, tracking drives, and other components can be shared, thus reducing the number of components. The reduction in the number of components is thought to significantly reduce cost. However, since the drives and tracking mechanisms are shared, accurate on-sun tracking of grouped heliostats becomes challenging because the angular degrees-of-freedom are now limited for the multiple number of combined heliostats. In this paper, the preliminary evaluation of the on-sun tracking of a novel tensile-based cable suspended ganged heliostat concept is provided. In this concept, multiple heliostats are attached to two guide cables. The cables are attached to rotation spreader arms which are anchored to end posts on two ends. The guide cables form a catenary which makes tracking on-sun interesting and challenging. Tracking is performed by rotating the end plates that the two cables are attached to and rotating the individual heliostats in one axis. An additional degree-of-freedom can be added by differentially tensioning the two cables, but this may be challenging to do in practice. Manual on-sun tracking was demonstrated on small-scale prototypes. The rotation arms were coarsely controlled with linear actuators, and the individual heliostats were hand-adjusted in local pitch angle and locked in place with set screws. The coarse angle adjustments showed the tracking accuracy was 3–4 milli-radians. However, with better angle control mechanisms the tracking accuracy can be drastically improved. In this paper, we provide tracking data that was collected for a day, which showed feasibility for automated on-sun tracking. The next steps are to implement better angle control mechanisms and develop tracking algorithms so that the ganged heliostats can automatically track.
Green Diesel From Microalgae
Authors: Costa Iago G. , Vargas José V. C. , Balmant Wellington , Z. Filho Arion , Ramos Luiz P. , Taher Dhyogo M. , Mariano André B.
Published: December 2019

This work developed a process of extraction of crude oil from microalgae for production of hydrocarbon based fuel (green diesel). The microalgae Tetradesmus obliquus were cultivated in 12 m3 compact photobioreactors (FBRS) for 15 days using biodigester effluent as nutrients. Microalgae oil was obtained from the dry biomass through hot extraction with organic solvents (hexane and ethanol). After extraction the solvents were recovered from the sample using evaporation methods. After solvent recovery, the results showed that with pure ethanol, only 1.7% w/w crude oil was obtained, whereas with a mixture of hexane and ethanol the yield was 11.1% w/w. Fractional distillation was used as purification methods of the compounds in order to separate the nonsterifiable portion. The first process (pure hexane) after purification delivered 0.4% w/w, and the second process (hexane and ethanol) yielded 6.3% w/w. In addition, the sample was characterized using gas chromatography coupled to a mass spectrometer (GC-MS). An average of 70.6% w/w hydrocarbons ranging from C11 to C22 was found in the first experimental condition, and the main compounds were undecane (8.1% w/w) and pentadecane (10.62% w/w). For the second experimental condition, about 79.6% w/w hydrocarbons were found that varied from C13 to C23 and the main compounds were pentadecane (13.5% w/w) and heptadecane (11.28% w/w). The lower heating value of the purified microalgae oil was measured as 42,464.6 kJ·kg−1, whereas petroleum-based diesel has a lower heating value of 42,500.2 kJ·kg−1. In sum, green diesel from microalgae was proven to have potential to be a concrete alternative to replace diesel from the technical point of view.