The influence of soil heterogeneity on exploratory tunnelling by the subterranean termite Coptotermes frenchi (Isoptera: Rhinotermitidae)

2003 ◽  
Vol 93 (5) ◽  
pp. 413-423 ◽  
Author(s):  
T.A. Evans
Keyword(s):  
Water Conservation ◽  
Field Data ◽  
Large Scale ◽  
Laboratory Experiments ◽  
Field Studies ◽  
Soil Heterogeneity ◽  
Large Field ◽  
Small Scale ◽  
Scale Field ◽  
Large Scale Field

AbstractThe exploration of sand-filled arenas by workers of an entire colony of the Australian, subterranean foraging, tree-nesting termite, Coptotermes frenchi Hill was investigated under laboratory conditions. The first experiment tested whether termite exploration of sand was influenced by the presence of gaps or objects in the sand. Gaps and objects were chosen to represent soil heterogeneity in the urban environment: gaps to represent tunnels dug by other animals, perspex strips to represent cables and pipes, and wood strips to represent roots. Termites always chose to explore gaps thoroughly before they began tunnelling in the sand. Significantly more and longer tunnels were excavated from the end of gaps at the far end of the arenas, and relatively little tunnelling occurred around and along objects. Termite density was significantly greater around and along wood compared with perspex blocks. The second experiment tested whether termite exploratory tunnelling was influenced by soil moisture. The termites tunnelled slowly in dry sand, but after discovering a patch of wet sand, increased tunnelling five-fold until it was completely explored, after which activity declined. Energy and water conservation may be behind these patterns of exploratory tunnelling as well as those seen in large field studies, but caution is urged when interpreting small scale laboratory experiments to explain large scale field data.

scholarly journals A Field Efficacy Evaluation of In2Care Mosquito Traps in Comparison with Routine Integrated Vector Management at Reducing Aedes aegypti

2021 ◽  
Vol 37 (4) ◽  
pp. 242-249
Author(s):  
Eva A. Buckner ◽  
Katie F. Williams ◽  
Samantha Ramirez ◽  
Constance Darrisaw ◽  
Juliana M. Carrillo ◽  
...  
Keyword(s):  
Aedes Aegypti ◽  
Large Scale ◽  
Pathogen Transmission ◽  
Small Scale ◽  
Integrated Vector Management ◽  
Control Programs ◽  
Vector Management ◽  
Scale Field ◽  
Large Scale Field ◽  
Eggs And Larvae

ABSTRACT Aedes aegypti is the predominant vector of dengue, chikungunya, and Zika viruses. This mosquito is difficult to control with conventional methods due to its container-inhabiting behavior and resistance to insecticides. Autodissemination of pyriproxyfen (PPF), a potent larvicide, has shown promise as an additional tool to control Aedes species in small-scale field trials. However, few large-scale field evaluations have been conducted. We undertook a 6-month-long large-scale field study to compare the effectiveness and operational feasibility of using In2Care Mosquito Traps (In2Care Traps, commercially available Aedes traps with PPF and Beauveria bassiana) compared to an integrated vector management (IVM) strategy consisting of source reduction, larviciding, and adulticiding for controlling Ae. aegypti eggs, larvae, and adults. We found that while the difference between treatments was only statistically significant for eggs and larvae (P < 0.05 for eggs and larvae and P > 0.05 for adults), the use of In2Care Traps alone resulted in 60%, 57%, and 57% fewer eggs, larvae, and adults, respectively, collected from that site compared to the IVM site. However, In2Care Trap deployment and maintenance were more time consuming and labor intensive than the IVM strategy. Thus, using In2Care Traps alone as a control method for large areas (e.g., >20 ha) may be less practical for control programs with the capacity to conduct ground and aerial larviciding and adulticiding. Based on our study results, we conclude that In2Care Traps are effective at suppressing Ae. aegypti and have the most potential for use in areas without sophisticated control programs and within IVM programs to target hotspots with high population levels and/or risk of Aedes-borne pathogen transmission.

scholarly journals Viscosity and Large-Scale Magnetic Fields from Accretion Disc Dynamos

1997 ◽  
Vol 163 ◽  
pp. 190-200
Author(s):  
Christopher A. Tout
Keyword(s):  
Magnetic Fields ◽  
Large Scale ◽  
Small Scale ◽  
Cascade Process ◽  
Jet Formation ◽  
Magnetohydrodynamic Turbulence ◽  
Discs Large ◽  
Scale Field ◽  
Large Scale Field ◽  
Nova Outbursts

AbstractWe review those processes associated with accretion discs that are probably influenced by magnetic fields, specifically, accretiondisc viscosity, energy dissipation and jet formation. We consider how magnetic instabilities in the disc can lead to a self-sustaining dynamical dynamo and how this is manifested as magnetohydrodynamic turbulence in numerical simulations. We show that currently these models do not fit with observational constraints imposed by dwarf-nova outbursts. We also show that the drop in ionisation fraction does not lead to the apparently necessary drop in viscosity in quiescent cataclysmic variable discs. Large-scale magnetic fields are required to launch and collimate jets form discs. We describe an inverse cascade process that can construct sufficient large-scale field from small-scale field generated by a dynamo.

scholarly journals Off-Site Lime Stabilisation as an Option to Treat Pit Latrine Faecal Sludge for Emergency and Existing On-Site Sanitation Systems

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Wilson Greya ◽  
Bernard Thole ◽  
Catherine Anderson ◽  
Flavius Kamwani ◽  
Jan Spit ◽  
...  
Keyword(s):  
Large Scale ◽  
Buffer Capacity ◽  
Hydrated Lime ◽  
Field Trials ◽  
Small Scale ◽  
E Coli ◽  
Scale Field ◽  
Large Scale Field ◽  
Sanitation Systems ◽  
Faecal Sludge

Off-site lime stabilisation for treating faecal sludge was assessed by undertaking small-scale (35 L) and large-scale (600 L) field trials in Blantyre, Malawi. Hydrated lime was dosed to maintain pH 10, pH 10.5, pH 11, pH 11.5, and pH 12 depending on the buffer capacity of the faecal sludge in the four replica small-scale field trials. Significant reduction of E. coli to below the detection limit of 104 CFU/100 mL within 1 hour of treatment was reported for pH > 11. Based on the small-scale findings, large-scale field trials were conducted and greater than 3 log removal of E. coli was observed under pH 12 conditions. Therefore, based on the study, off-site lime stabilisation by dosing lime in the range of 10–35% w/w (dry solid basis), depending on the buffer capacity and solids content of the sludge to maintain pH > 11, can be used to sanitise faecal sludge during emergencies, as well as for existing on-site sanitation systems.

The Smartphone as a Pacifying Technology

2020 ◽  
Vol 47 (2) ◽  
pp. 237-255 ◽  
Author(s):  
Shiri Melumad ◽  
Michel Tuan Pham
Keyword(s):  
Large Scale ◽  
Laboratory Experiments ◽  
Stress Relief ◽  
Unique Combination ◽  
Personal Nature ◽  
Scale Field ◽  
Large Scale Field ◽  
Underlying Mechanisms ◽  
The Relationship ◽  
Actual Stress

Abstract In light of consumers’ growing dependence on their smartphones, this article investigates the nature of the relationship that consumers form with their smartphone and its underlying mechanisms. We propose that in addition to obvious functional benefits, consumers in fact derive emotional benefits from their smartphone—in particular, feelings of psychological comfort and, if needed, actual stress relief. In other words, in a sense, smartphones are not unlike adult pacifiers. This psychological comfort arises from a unique combination of properties that turn smartphones into a reassuring presence for their owners: the portability of the device, its personal nature, the subjective sense of privacy experienced while on the device, and the haptic gratification it affords. Results from one large-scale field study and three laboratory experiments support the proposed underlying mechanisms and document downstream consequences of the psychological comfort that smartphones provide. The findings show, for example, that (a) in moments of stress, consumers exhibit a greater tendency to seek out their smartphone (study 2); and (b) engaging with one’s smartphone provides greater stress relief than engaging in the same activity with a comparable device such as one’s laptop (study 3) or a similar smartphone belonging to someone else (study 4).

scholarly journals Announcements of Support and Public Good Provision

2017 ◽  
Vol 107 (12) ◽  
pp. 3760-3787 ◽  
Author(s):  
Judd B. Kessler
Keyword(s):  
Public Goods ◽  
Field Experiment ◽  
Prosocial Behavior ◽  
Public Good ◽  
Large Scale ◽  
Laboratory Experiments ◽  
Public Good Provision ◽  
Scale Field ◽  
Large Scale Field ◽  
Good Provision

Providing information about contributions to public goods is known to generate further contributions. However, it is often impossible to provide verifiable information on contributions. Through a large-scale field experiment and a series of laboratory experiments, I show that nonbinding announcements of support for a public good encourage others to contribute, even when actual contributions might not or cannot be made. Providing a way to easily announce support for a charity increases donations by $865 per workplace fundraising campaign (or 16 percent of average giving). I discuss implications for understanding prosocial behavior and for organizations aiming to increase contributions to public goods. (JEL C93, D64, D83, H41, L31)

scholarly journals PENGEMBANGAN MEDIA PANLINTARMATIKA (PAPAN PERKALIAN PINTAR MATEMATIKA) MATERI PERKALIAN UNTUK SISWA SEKOLAH DASAR

2021 ◽  
Vol 2 (1) ◽  
pp. 41-47
Author(s):  
Hasna Nur Afifah ◽  
Meita Fitrianawati
Keyword(s):  
Data Analysis ◽  
Field Test ◽  
Large Scale ◽  
Field Testing ◽  
Small Scale ◽  
Quantitative Data Analysis ◽  
Scale Field ◽  
Large Scale Field ◽  
The Media ◽  
Information Collecting

This study aims to 1) find out the steps in developing Panlintarmatika learning media, 2) know the feasibility of developing Panlintarmatika learning media based on experts.  This study is a type of Research and Development (RD) research using the Borg and Gal model which consists of: (1) research and information collecting, (2) planning, (3) developing preliminary from a product, (4) prelimunary field testing,  (5) main product revision, (6) main field testing, (7) operational product revision (8) operational field testing.  The trial subjects used were 18 grade 2 students and teachers at SD N Kalangan.  Data collection techniques in the form of observation, interviews and questionnaires.  Data analysis includes quantitative data analysis and qualitative data analysis.  The results showed that the validation of the media experts received a score of 60 in the "Very good" category, the validation of the material experts received a score of 42 in the "Good" category and the learning expert received a score of 60 in the "Good" category.  The results of the small-scale field test students get a score of 100 with the category "Very Good" and the teacher gets a score of 94 with the category "Very Good".  Large-scale field test results students get a score of 100 with the category "Very Good" and the teacher scores 98 with a score of "Very Good" It can be concluded that the Panlintarmatika learning media is feasible and can be used as class 2 learning multiplication material

scholarly journals Advection/diffusion of large scale magnetic field in accretion disks

2009 ◽  
Vol 16 (1) ◽  
pp. 77-81 ◽  
Author(s):  
R. V. E. Lovelace ◽  
G. S. Bisnovatyi-Kogan ◽  
D. M. Rothstein
Keyword(s):  
Magnetic Field ◽  
Large Scale ◽  
Turbulent Viscosity ◽  
Pressure Ratio ◽  
Rotational Instability ◽  
Small Scale ◽  
Magnetic Diffusivity ◽  
Large Scale Magnetic Field ◽  
Scale Field ◽  
Large Scale Field

Abstract. Activity of the nuclei of galaxies and stellar mass systems involving disk accretion to black holes is thought to be due to (1) a small-scale turbulent magnetic field in the disk (due to the magneto-rotational instability or MRI) which gives a large viscosity enhancing accretion, and (2) a large-scale magnetic field which gives rise to matter outflows and/or electromagnetic jets from the disk which also enhances accretion. An important problem with this picture is that the enhanced viscosity is accompanied by an enhanced magnetic diffusivity which acts to prevent the build up of a significant large-scale field. Recent work has pointed out that the disk's surface layers are non-turbulent and thus highly conducting (or non-diffusive) because the MRI is suppressed high in the disk where the magnetic and radiation pressures are larger than the thermal pressure. Here, we calculate the vertical (z) profiles of the stationary accretion flows (with radial and azimuthal components), and the profiles of the large-scale, magnetic field taking into account the turbulent viscosity and diffusivity due to the MRI and the fact that the turbulence vanishes at the surface of the disk. We derive a sixth-order differential equation for the radial flow velocity vr(z) which depends mainly on the midplane thermal to magnetic pressure ratio β>1 and the Prandtl number of the turbulence P=viscosity/diffusivity. Boundary conditions at the disk surface take into account a possible magnetic wind or jet and allow for a surface current in the highly conducting surface layer. The stationary solutions we find indicate that a weak (β>1) large-scale field does not diffuse away as suggested by earlier work.

scholarly journals Pengembangan Alat Peraga Taktual Model Atom untuk Siswa Tunanetra Kelas VIII

INKLUSI ◽  
2014 ◽  
Vol 1 (2) ◽  
pp. 159
Author(s):  
Wahyu Triningsih ◽  
Winarti Winarti
Keyword(s):  
Large Scale ◽  
Student Response ◽  
Atomic Model ◽  
Small Scale ◽  
Product Analysis ◽  
Expert Teacher ◽  
Scale Field ◽  
Large Scale Field ◽  
Research Procedure ◽  
Grade 3

The research purposes to (1) produce atomic model tactual props and material guidance of atomic model for blind student on eight grade, (2) know quality of atomic model tactual props and material guidance of atomic model for blind student on eight grade, (3) know student response toward atomic model tactual props and material guidance of atomic model for blind student on eight grade.This is a developmental research based on a procedural model. The development procedure is based on the development research procedure by Puslitjaknov Team that is adapted from Borg and Gallresearch procedure with development steps such as (1) doing product analysis that will be developed, (2) developing preliminary product, (3) experts validation and revision, (4) small scale field test and product revision, and (5) large scale field and final product. Collecting data technique by a non test research instruments are developed by such as validation sheet, appraisal sheet and student response. The analyzing data technique is done by changing the quantitative data into qualitative data.This research produced an atomic model tactual props and material guidance for blind student on eight grade. Based on the appraisal of media expert, material expert, teacher, atomic and students this prop has a very good quality.

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