bluuebunny/crossref_metadata_2025_split huggingface dataset:
Climate-driven oscillation of phosphorus and iron limitation in the North Pacific Subtropical Gyre
Authors: Letelier Ricardo M. , Björkman Karin M. , Church Matthew J. , Hamilton Douglas S. , Mahowald Natalie M. , Scanza Rachel A. , Schneider Niklas , White Angelicque E. , Karl David M. 
Published: June 2019

Significance
Characterizing the mechanisms driving spatial and temporal changes in the stoichiometry of nutrient supply is crucial to understand the controls of an ecosystem’s carrying capacity and productivity. In marine oligotrophic regions, small changes in the ocean and atmospheric nutrient input ratio can shift the nature of the limiting nutrient. The present study documents such a shift at interannual scales between periods of phosphorus limitation and sufficiency in the North Pacific Subtropical Gyre. These shifts appear to be driven by interannual variations in the transport of iron-rich Asian dust across the North Pacific resulting from basin-scale changes in atmospheric pressure gradients, as reflected by the Pacific Decadal Oscillation index, causing the ecosystem to oscillate between phosphorus and iron limitation.
Periodic catastrophes over human evolutionary history are necessary to explain the forager population paradox
Authors: Gurven Michael D. , Davison Raziel J. 
Published: June 2019

SignificanceMuch of what is known about human life histories is based on studying modern hunter-gatherers experiencing rapid population growth. Yet, if populations are near-stationary over most of their evolutionary history, the positive growth of contemporary foragers is puzzling and potentially unrepresentative. Investigating multiple demographic scenarios in a large sample of human and chimpanzee populations, we find that periodic catastrophes combined with plausible fertility or mortality reductions can reasonably generate zero population growth. Our findings bolster arguments about the role of intergenerational cooperation and cumulative culture in supporting the colonizing potential of human populations once released from catastrophes.
Oxidation of PKGIα mediates an endogenous adaptation to pulmonary hypertension
Authors: Rudyk Olena , Rowan Alice , Prysyazhna Oleksandra , Krasemann Susanne , Hartmann Kristin , Zhang Min , Shah Ajay M. , Ruppert Clemens , Weiss Astrid , Schermuly Ralph T. , Ida Tomoaki , Akaike Takaaki , Zhao Lan , Eaton Philip 
Published: June 2019

Significance
This study demonstrates that oxidation of protein kinase G Iα (PKGIα) to its disulfide-activated state occurs in pulmonary arteries during chronic hypoxia, and that this is a protective event that limits progression of pulmonary hypertension by at least two mechanisms. Firstly, it induces pulmonary vasodilation that counters and offsets maladaptive vasoconstriction during chronic hypoxia, and, secondly, disulfide PKGIα is protective by preventing maladaptive growth and fibrosis signaling. Consistent with oxidation of PKGIα being protective, administration of polysulfides to mice during hypoxia, which increased the abundance of the disulfide form of the kinase, was therapeutic and limited disease progression.
Differential invariants of Kundt waves
Authors: Kruglikov Boris , McNutt David , Schneider Eivind 
Published: June 2019

Abstract
Kundt waves belong to the class of spacetimes which are not distinguished by their scalar curvature invariants. We address the equivalence problem for the metrics in this class via scalar differential invariants with respect to the equivalence pseudo-group of the problem. We compute and finitely represent the algebra of those on the generic stratum and also specify the behavior for vacuum Kundt waves. The results are then compared to the invariants computed by the Cartan–Karlhede algorithm.
Coherent coupling of single molecules to on-chip ring resonators
Authors: Rattenbacher Dominik , Shkarin Alexey , Renger Jan , Utikal Tobias , Götzinger Stephan , Sandoghdar Vahid 
Published: June 2019

Abstract
We report on cryogenic coupling of organic molecules to ring microresonators obtained by looping subwavelength waveguides (nanoguides). We discuss fabrication and characterization of the chip-based nanophotonic elements which yield a resonator finesse in the order of 20 when covered by molecular crystals. Our observed extinction dips from single molecules reach 22%, consistent with an expected enhancement factor of up to 11 for the molecular emission into the nanoguide. Future efforts will aim at efficient coupling of a handful of molecules via their interaction with a ring microresonator mode, setting the ground for the realization of quantum optical cooperative effects.
Negative differential response in chemical reactions
Authors: Falasco Gianmaria , Cossetto Tommaso , Penocchio Emanuele , Esposito Massimiliano 
Published: June 2019

Abstract
Reaction currents in chemical networks usually increase when increasing their driving affinities. But far from equilibrium the opposite can also happen. We find that such negative differential response (NDR) occurs in reaction schemes of major biological relevance, namely, substrate inhibition and autocatalysis. We do so by deriving the full counting statistics of two minimal representative models using large deviation methods. We argue that NDR implies the existence of optimal affinities that maximize the robustness against environmental and intrinsic noise at intermediate values of dissipation. An analogous behavior is found in dissipative self-assembly, for which we identify the optimal working conditions set by NDR.
Passive survivability of buildings under changing urban climates across eight US cities
Authors: Baniassadi Amir , Sailor David J , Krayenhoff E Scott , Broadbent Ashley M , Georgescu Matei 
Published: June 2019

Abstract
In the US, more than 80% of fatal cases of heat exposure are reported in urban areas. Notably, indoor exposure is implicated in nearly half of such cases, and lack of functioning air conditioning (AC) is the predominant cause of overheating. For residents with limited capacity to purchase, maintain, and operate an AC system, or during summertime power outages, the ability of buildings to maintain safe thermal conditions without mechanical cooling is the primary protective factor against heat. In this paper, we use whole-building energy simulations to compare indoor air temperature inside archetypical single-family residential buildings without AC at the start and middle of the century in eight US cities. We ran the models using hourly output from 10 year regional climate simulations that explicitly include heating from mid-century projections of urban development and climate change under a ‘business-as-usual’ emissions scenario. Moreover, to identify the impacts from evolving construction practices, we compare different versions of building energy standards. Our analysis shows that summertime overheat time may increase by up to 25% by the middle of century. Moreover, we find that, while newer building energy codes reduce thermal comfort under moderate outdoor weather, they perform better under extreme heat.
Screening of polyhydroxyalkanoates (PHA)-producing bacteria from soil bacteria strains
Authors: Ratnaningrum D , Saraswaty V , Priatni S , Lisdiyanti P , Purnomo A , Pudjiraharti S 
Published: June 2019

Abstract
Plastic wastes and petrochemical-based polymer materials have become a serious problem to the environment due to the characteristics of these materials that are difficult to degrade in nature. Polyhydroxyalkanoates (PHA) is one type of biodegradable plastics that have a great potential to replace the widely-used hydrocarbon plastics since it will decompose completely into carbon dioxide and water after burial for several months in the soil. PHA can be produced by microorganisms such as bacteria and algae through a fermentation process. The objective of this research is to obtain bacteria that can produce PHA. Screening was carried out by two sequential steps, qualitative and followed by quantitative methods. An amount of 29 bacteria strains isolated from Indonesians soil were screened for this purpose. The qualitative screening was conducted by growing the bacteria in a specific medium containing Nile red dye. The results showed that 19 strains were positive, generated pink to orange colonies under UV light at 235 nm. It was also confirmed by fluorescence microscope. The quantitative screening was performed by measuring the intracellular materials (predicted as PHA) of the bacterial cells by gravimetric method. The results indicated that the highest average of PHA content was 52.9%, 35.6% and 35.4 of dried cell weight, respectively for the Burkholderia sp B73, Bacillus sp B58, Bacillus toyonensis B50 and Staphylococcus cohni B66.
Antioxidant activity of biocellulose-based films incorporated with powder of soursop leaves (Annona muricata L)
Authors: Srikandace Y , Indriyati  
Published: June 2019

Abstract
Biocelluloses are natural materials that are produced from Acetobacter sp through fermentation in coconut water as the medium. In this study, biocellulose-based edible film was used as the carrier film for the antioxidant agents (the soursop leave powder (Annona muricata L)). This leave is considered as a good source of natural antioxidant, while all parts of the fruit are used in traditional medicine. This work aimed to evaluate the antioxidant activity of biocellulose-based edible film added with soursop leave powder. The biocellulose was formed in slurry and leaves of fruit was crushed into powder. The edible films were prepared by mixing biocellulose slurry, carboxy methyl cellulose (CMC) as the homogenizer, and the leaves powder, casting, and drying in the oven at 40 °C for 24 h. The IC50 of methanol extract of leaves powder and edible film containing 0.2 g leaves powder were 89.89 mg/mL and 363.26 mg/mL, respectively. All methanol extracts of edible films incorporated with soursop leaves powder inhibited DPPH about 71.10-86.80% and they remained above 70% after storage in a plastic bag at room temperature for one month. The edible films also had the thickness of 0.040-0.067 mm, the solubility of 80.30-90.20% and all compounds of edible films were still available based on SEM and FTIR results.
Performance of Single Chamber Microbial Fuel Cell (SCMFC) for biological treatment of tofu wastewater
Authors: Permana D , Djaenudin  
Published: June 2019

Abstract
The wastewater of tofu industries consists of organic compounds and in turn, may affect the environment; therefore, a proper wastewater treatment system is needed. Based on its characteristics, biological treatment is a good method to treat tofu wastewater. One of the biological treatment methods that can be used is Microbial Fuel Cell (MFC), which can reduce the pollutant and at the same time generating low-power electricity. This system utilizes microorganisms as a biocatalyst to degrade organic compounds in the wastewater. This study aimed to examine the performance of Single Chamber MFC (SCMFC) to decrease biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) of the tofu wastewater, as well as to generate electricity. Tofu wastewater was sterilized then filled into the reactor. Microbes that either have been acclimatized or not acclimatized were then added. Bacteria that were used were one of the three consortiums of native microbes of tofu wastewater, namely Escherichia coli, Saccharomycopsis fibuligera, and mixed culture of E. coli and S. fibuligera. Carbon (C) was used as both anode and cathode. We found that the acclimatized mixed culture of E. coli and S. fibuligera showed high BOD5, COD removal after 48 hours at 76.57 and 77.22 %, respectively. It also generated 5.49 mA of current, 757 mV of voltage, and the electrical energy produced was 9.216 x10− 5 kWh. The results suggest that using mixed microorganisms is one of the strategies to improve the electricity generation of MFC. The scale-up of the volume, selection of microorganism cultures, and immobilization could be other strategies for further studies.
The performance analysis of a pico-hydro pump as turbine power plant
Authors: Zariatin D L , Shulhanuddin  , Danuriyanto F , Suwandi A 
Published: June 2019

Abstract
Hydropower plant is a type of green technologies to generate electricity. One type of hydropower plants is Pump as Turbine (PAT), an economical alternative to building a power plant with small flow water (pico-hydro). The working principle of the PAT is by reversing the pump working. At PAT, the water flow enters the pump in the discharge section and exit through the suction section of the pump. Centrifugal pump is one type of pumps suitable for use as PAT. The motor from the centrifugal pump can be converted into a generator by replacing the magnetic shaft of the stator. The implementation of PAT was performed on Cibalok Waterfall, with a height of 2.5 m and a water flow of 31.915 L/sec at 70 cm water level. Grundfos NF 30-18 centrifugal pump was used at the implementation. Two models of impellers and two water inlet conditions were tested for comparison. The first model of the impeller was the original impeller from Grundfos NF 30-18 with steel metal material. The second model of the impeller was a modified impeller with a brass metal material. Meanwhile, the two water inlet conditions were a single inlet with a 4-inches diameter and an inlet with two 4-inches pipes. The experiments show that compared to the second model of the impeller, the first model of the impeller with two inlets of 4-inches pipes generated maximum water flow-rate, rotation speed and electrical power at 2.42 L/s, 1134.9 rpm, and 12.05 W, respectively.
Experimental Research on the Influence of Vibration Intensity on Performance of Cement Stabilized Macadam
Authors: Dong Wu , Feng Zhongxu , Zhao Lijun 
Published: June 2019

Abstract
In order to study the influence of different vibration intensity on the performance of cement stabilized gravel. Vibration mixing tests of cement stabilized gravel with 5% cement factor were carried out under different vibration intensity, Through the preparation and maintenance of cylindrical specimen and the mid-beam specimen, The unconfined compressive strength test and the drying shrinkage test were carried out, Vibratory mixing can significantly improve the strength of cement stabilized gravel and reduce the level of intensity variation, As the vibration intensity increases, the increase range of specimen strength increases first and then decreases, Considering the mechanical reliability factors, It is reasonable to increase the strength of the material when the vibration intensity is D = 2 ∼ 3. Vibration mixing can improve drying shrinkage property of cement stabilized gravel, the vibration mixing reduces the water loss rate of the specimen at the later stage of shrinkage, with the increase of vibration intensity, the variation of dry shrinkage coefficient becomes smaller during shrink age period, and the coefficient of dry shrinkage decreases with it, Therefore, the greater the vibration intensity, the better drying shrinkage property of cement stabilized gravel. Vibration mixing can improve the mechanical behavior and cracking resistance of cement stabilized gravel simultaneously, it has a wide application prospect.
Experimental Study on Acoustic Emission Characteristics of Intermittent Jointed Rock Mass Under Uniaxial Compression
Authors: Zhu Le , Zhang Yan , Dong Lu , Wu Jiawen , Duan Liqun , Zhang Li 
Published: June 2019

Abstract
Using large size of intact and intermittent jointed rocks made with equivalent materials, the stress-stain curves, ringing counts and energy accumulation of acoustic emission (AE) were obtained by AE monitoring in real time under uniaxial compression. The strength, deformation, progressive failure evolution and AE properties of two kinds of rock samples were compared. Through the analysis of AE parameters, the results indicate that the sudden increase of AE ringing counts and AE energy may be utilized as precursor information for the failure of rocks. AE location may directly reflect the dynamic evolvement process of rock cracks. Unlike the failure of intact rock sample, the AE ringing counts and energy curves of jointed rock sample show obvious multi-peaks, and the final peak appears behind the stress peak. The failure mode of intact rock is mainly vertical tensile breakage, whereas the tensile wing crack propagates through the joint surface, resulting in the failure of jointed rock sample.
Analysis of Seismic Isolation Effect of Rubber Bearings with Different Periods of Isolated Structures
Authors: Qin Shuiqiang , Song Xiaosheng , Wang Shuo , Du Dandan 
Published: June 2019

Abstract
In order to investigate the isolation performance and economic advantages of different period isolation structures, the isolation design and analysis of different period isolation structures are carried out with an office building as the background, and the related structure, structural design and engineering economy are discussed. Time history analysis shows that under the action of 8 degree earthquake, the isolation performance of short-period isolation structure is better than that of long-period isolation structure; engineering economic analysis shows that when the tensile stress exceeds the limit of the isolation bearing, special measures are needed for adjustment. Will result in a substantial increase in project cost.
Empirical Shear Strength Criterion for Artificial Joint
Authors: Tan Ran , Chai Junrui , Cao Cheng 
Published: June 2019

Abstract
An accurate understanding of shear strength in joints is critical to effective geotechnical engineering. The complete rock shear test continues to shear after shear strength reaches it speak value, resulting in the appearance of a softening stage and a residual stage. Existing research is mainly aimed at the development of dilatancy and shear models of peak strength; few consider post peak processes. This paper attempted to develop a better understanding of changes to shear strength during shear. Direct shear tests of artificial rock joints with the same shape were conducted under the action of 5 normal stresses. By determining a shear dilatancy angle model for the shear process, shear strength can be determined using the Mohr-Coulomb law. The values calculated using our new method agree well with experimental results, indicating that the criterion can be used to accurately estimate the shear strength of rock joints. The parameters required by the proposed criterion can be easily determined in test.
Study on Bias Characteristics of Multi Arch Tunnel Under Different Side Overburden Thickness
Authors: Zhang Jinrui , Zhang Chengliang , Wang Chenhui , Shi Jiangxu 
Published: June 2019

Abstract
The entrance and exit of the Qifengshan tunnel are shallow and the pressure has a certain offset, the overlying soil layer is thin, and the stability is poor. After the excavation disturbance, the upper soil layer tends to slide. The excavation of black holes often causes large deformation, collapse and instability of surrounding rock. In this paper, combined with the geological conditions of the multi arch tunnel and the mechanical characteristics of surrounding rock, the theoretical analysis and numerical simulation are used to study the deformation law of the buried depth, side cover soil thickness and the stress and displacement of the surrounding rock after excavation. The results show that the bias stress of the tunnel under the vertical direction increases with the depth of the buried tunnel. The bias stress of the tunnel in the vertical direction decreases with the increase of the buried depth. The shallower the buried depth is, the more obvious the bias effect is. When the depth of burial exceeds 20m, the increased amount of bias stress is gradually reduced after the bias is applied. The vertical deformation characteristics of the rock mass caused by tunnel excavation with different thickness of the tunnel are analyzed. The vertical displacement is gradually reduced with the increase of the thickness of the side covering layer. When the thickness of the overlying soil is more than 21m, the vertical displacement is less affected by the thickness of the side cladding soil, basically only by the surrounding rock itself.
Knowledge Translation in Oncology
Authors: Morgan Sarah , Hanna Jessica , Yousef George M 
Published: June 2019

Abstract

Objectives
Knowledge translation (KT) is the dynamic process of mobilizing best-practice evidence to guide health care decisions.

Methods
Using a PubMed search, challenges were identified and milestones defined.

Results
Substantial challenges exist in integrating discoveries into patient care, including technical limitations related to genomic testing like turnaround time, standardization, reproducibility, and results interpretation. Other challenges include lack of proper training in genetic counseling for health care providers, clarity of scientific evidence, and ethical, legal and social considerations. In addition, most health care systems lack accessibility to genetic testing services. Moving forward, KT should be addressed at three main frontiers. The first is patients centered for proper understanding and decision making; the second is directed toward health care professionals, including clinical decision support and clarity of roles; and the third addresses resources of health care systems.

Conclusions
Implementing KT requires developing strategies to enhance awareness and promote behavioral changes congruent with research evidence, designing a systematic approach by health care providers and stakeholders to achieve patient-centered care.
Differences in the use of surface water resources by desert birds are revealed using isotopic tracers
Authors: Smit Ben , Woodborne Stephan , Wolf Blair O , McKechnie Andrew E 
Published: June 2019

Abstract
The scarcity of free-standing water sources is a key determinant of animal and plant community structure in arid environments, and an understanding of the extent to which particular species use surface water is vital for modeling the effects of climate change on desert avifauna. We investigated interspecific variation in the use of artificial water sources among birds in the Kalahari Desert, South Africa, by (i) observations at waterholes and (ii) tracing spatial water-use patterns during summer by isotopically labeled water sources and blood sampling. More than 50% of the avian community (primarily insectivores and omnivores) were not observed to drink. The majority (53%) of species drinking at waterholes were granivorous, and their use of surface water was best predicted by their relative abundance in the community. Species representing the remaining dietary guilds drank significantly more on hot days. Blood samples revealed that only 11 of 42 species (mostly granivores and a few omnivores) showed evidence of drinking at a waterhole with enriched deuterium values; on average, in the latter birds, water from the enriched waterhole accounted for ~38% of their body water pool. These findings illustrate that 2 methods employed in this study provide different, but complementary data on the relative importance of a water source for an avian community. Although our results suggest that most avian species are independent of surface water, drinking patterns on the hottest days during our study period suggest that free-standing water might become more important for some of the non-drinking species under hotter climatic conditions.