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Small-Scale Food Animal Production and Antimicrobial Resistance: Mountain, Molehill, or Something in-between?
SummarySmall-scale food animal production is widely practiced around the globe, yet it is often overlooked in terms of the environmental health risks. Evidence suggests that small-scale food animal producers often employ the use of antimicrobials to improve the survival and growth of their animals, and that this practice leads to the development of antimicrobial resistance (AMR) that can potentially spread to humans. The nature of human-animal interactions in small-scale food animal production systems, generally practiced in and around the home, likely augments spillover events of AMR into the community on a scale that is currently unrecognized and deserves greater attention. https://doi.org/10.1289/EHP2116
PENGGUNAAN MODEL PEMBELAJARAN INKUIRI TERBIMBING UNTUK MENINGKATKAN HASIL BELAJAR PESERTA DIDIK
Penelitian ini dilatar belakangi oleh rendahnya sikap rasa ingin tahu dan hasil belajar
peserta didik pada Subtema Makananku Sehat dan Bergizi yang pencapaiannya hanya
35% peserta didik yang tuntas memenuhi nilai KKM. Selain itu pendidik masih
menggunakan metode atau model pembelajaran yang bersifat teacher centered, yaitu
model ceramah.Pelaksanaan yang dilakukan peneiti yaitu dua siklus dan setiap siklus
terdiri dari 3 pembelajaran.Model Pembelajaran yang digunakan peneliti yaitu inkuiri
terbimbing, pengertian dari inkuiri terbimbing merupakan model pembelajaran yang
memberikan kesempatan kepada peserta didik untuk aktif terlibat dalam proses
pembelajaran dengan melakukan penyelidikan dan pemecahan masalah secara
mandiri namum tetap dengan bimbingan pendidik agar peserta didik lebih mudah
dalam memahami konsep pelajaran. Subjek penelitian ini adalah siswakelas IV D
SDN Leuwipanjang dengan jumlah peserta didik sebanyak 35 orang. Instrument
pembelajaran yang digunakan adalah berupa tes, lembar observasi (observasi
pendidik dan observasi peserta didik), LKPD (Lembar Kerja Peserta Didik) dan
lembar angket. Hasil penelitian dengan menggunakan model pembelajaran inkuiri
terbimbing ditunjukan dengan perencanaan setiap siklusnya yang mengalami
perbaikan berdasarkan hasil refleksi di siklus sebelumnya. Pelaksanaan pembelajaran
dengan menggunakan model pembelajaran inkuiri terbimbing dapat dilihat dari
aktivitas pendidik dan peserta didik pada setiap siklusnya yang mengalami
peningkatan. Pencapaian hasil belajar afektif mencapai 44% pada siklus II mencapai
80% dan kognitif peserta didik pada siklus I mencapai rata-rata 35% Siklus II
ketuntasan 80%. Adapun hasil belajar psikomotor peserta didik di siklus I mencapai
ketuntasan 36%. Siklus II mencapai mencapai ketuntasan 88%. Ambatan yang dilami
oleh peneiti yaitu alokasi waktu dan pengelolaan kelas, Upaya yang dilakukan
peneliti adalah mengatur pelaksannaan pembelajaran sesuai dengan rencana yang kita
persiapkan dengan baik dan mengatur suasana kelas dengan menyenangkan yaitu
membuat media pembelajaran yang baik sehingga daapat menarik minat belajar
peserta didik.
Kata Kunci : Inkuiri Terbimbing, rasa ingin tahu, hasil belajar peserta didik,
hambatan pelaksanaan, upaya peningkata
Mathematics difficulties in extremely preterm children : evidence of a specific deficit in basic mathematics processing
Background:
Extremely preterm (EP, <26 wk gestation) children have been observed to have poor academic achievement in comparison to their term-born peers, especially in mathematics. This study investigated potential underlying causes of this difficulty.
Methods:
A total of 219 EP participants were compared with 153 term-born control children at 11 y of age. All children were assessed by a psychologist on a battery of standardized cognitive tests and a number estimation test assessing children’s numerical representations.
Results:
EP children underperformed in all tests in comparison with the term controls (the majority of Ps < 0.001). Different underlying relationships between performance on the number estimation test and mathematical achievement were found in EP as compared with control children. That is, even after controlling for cognitive ability, a relationship between number representations and mathematical performance persisted for EP children only (EP: r = 0.346, n = 186, P < 0.001; control: r = 0.095, n = 146, P = 0.256).
Conclusion:
Interventions for EP children may target improving children’s numerical representations in order to subsequently remediate their mathematical skills
Equality of Participation Online Versus Face to Face: Condensed Analysis of the Community Forum Deliberative Methods Demonstration
Online deliberation may provide a more cost-effective and/or less inhibiting
environment for public participation than face to face (F2F). But do online
methods bias participation toward certain individuals or groups? We compare F2F
versus online participation in an experiment affording within-participants and
cross-modal comparisons. For English speakers required to have Internet access
as a condition of participation, we find no negative effects of online modes on
equality of participation (EoP) related to gender, age, or educational level.
Asynchronous online discussion appears to improve EoP for gender relative to
F2F. Data suggest a dampening effect of online environments on black
participants, as well as amplification for whites. Synchronous online voice
communication EoP is on par with F2F across individuals. But individual-level
EoP is much lower in the online forum, and greater online forum participation
predicts greater F2F participation for individuals. Measured rates of
participation are compared to self-reported experiences, and other findings are
discussed.Comment: 14 pages, 10 tables, to appear in Efthimios Tambouris, Panos
Panagiotopoulos, {\O}ystein S{\ae}b{\o}, Konstantinos Tarabanis, Michela
Milano, Theresa Pardo, and Maria Wimmer (Editors), Electronic Participation:
Proceedings of the 7th IFIP WG 8.5 International Conference, ePart 2015
(Thessaloniki, August 30-September 2), Springer LNCS Vol. 9249, 201
Milling plant and soil material in plastic tubes over-estimates carbon and under-estimates nitrogen concentrations
Peer reviewedPostprin
Bird pollination of Canary Island endemic plants
The Canary Islands are home to a guild of endemic, threatened bird pollinated plants. Previous work has suggested that these plants evolved floral traits as adaptations to pollination by flower specialist sunbirds, but subsequently they appear to be have co-opted passerine birds as sub-optimal pollinators. To test this idea we carried out a quantitative study of the pollination biology of three of the bird pollinated plants, Canarina canariensis (Campanulaceae), Isoplexis canariensis (Veronicaceae) and Lotus berthelotii (Fabaceae), on the island of Tenerife. Using colour vision models, we predicted the detectability of flowers to bird and bee pollinators. We measured pollinator visitation rates, nectar standing crops, as well as seed set and pollen removal and deposition. These data showed that the plants are effectively pollinated by non-flower specialist passerine birds that only occasionally visit flowers. The large nectar standing crops and extended flower longevities (>10days) of Canarina and Isoplexis suggests that they have evolved bird pollination system that effectively exploits these low frequency non-specialist pollen vectors and is in no way suboptimal. Seed set in two of the three species was high, and was significantly reduced or zero in flowers where pollinator access was restricted. In L. berthelotii, however, no fruit set was observed, probably because the plants were self incompatible horticultural clones of a single genet. We also show that, while all three species are easily detectable for birds, the orange Canarina and the red Lotus (but less so the yellow-orange Isoplexis) should be difficult to detect for insect pollinators without specialised red receptors, such as bumblebees. Contrary to expectations if we accept that the flowers are primarily adapted to sunbird pollination, the chiffchaff (Phylloscopus canariensis) was an effective pollinator of these species
Self-Organization, Layered Structure, and Aggregation Enhance Persistence of a Synthetic Biofilm Consortium
Microbial consortia constitute a majority of the earth’s biomass, but little is known about how these cooperating
communities persist despite competition among community members. Theory suggests that non-random spatial structures
contribute to the persistence of mixed communities; when particular structures form, they may provide associated
community members with a growth advantage over unassociated members. If true, this has implications for the rise and
persistence of multi-cellular organisms. However, this theory is difficult to study because we rarely observe initial instances
of non-random physical structure in natural populations. Using two engineered strains of Escherichia coli that constitute a
synthetic symbiotic microbial consortium, we fortuitously observed such spatial self-organization. This consortium forms a
biofilm and, after several days, adopts a defined layered structure that is associated with two unexpected, measurable
growth advantages. First, the consortium cannot successfully colonize a new, downstream environment until it selforganizes
in the initial environment; in other words, the structure enhances the ability of the consortium to survive
environmental disruptions. Second, when the layered structure forms in downstream environments the consortium
accumulates significantly more biomass than it did in the initial environment; in other words, the structure enhances the
global productivity of the consortium. We also observed that the layered structure only assembles in downstream
environments that are colonized by aggregates from a previous, structured community. These results demonstrate roles for
self-organization and aggregation in persistence of multi-cellular communities, and also illustrate a role for the techniques
of synthetic biology in elucidating fundamental biological principles
Decoherence induced deformation of the ground state in adiabatic quantum computation
Despite more than a decade of research on adiabatic quantum computation
(AQC), its decoherence properties are still poorly understood. Many theoretical
works have suggested that AQC is more robust against decoherence, but a
quantitative relation between its performance and the qubits' coherence
properties, such as decoherence time, is still lacking. While the thermal
excitations are known to be important sources of errors, they are predominantly
dependent on temperature but rather insensitive to the qubits' coherence. Less
understood is the role of virtual excitations, which can also reduce the ground
state probability even at zero temperature. Here, we introduce normalized
ground state fidelity as a measure of the decoherence-induced deformation of
the ground state due to virtual transitions. We calculate the normalized
fidelity perturbatively at finite temperatures and discuss its relation to the
qubits' relaxation and dephasing times, as well as its projected scaling
properties.Comment: 10 pages, 3 figure
Chemical cues and pheromones in the sea lamprey (Petromyzon marinus)
Chemical cues and pheromones guide decisions in organisms throughout the animal kingdom. The neurobiology, function, and evolution of olfaction are particularly well described in insects, and resulting concepts have driven novel approaches to pest control. However, aside from several exceptions, the olfactory biology of vertebrates remains poorly understood. One exception is the sea lamprey (Petromyzon marinus), which relies heavily upon olfaction during reproduction. Here, we provide a broad review of the chemical cues and pheromones used by the sea lamprey during reproduction, including overviews of the sea lamprey olfactory system, chemical cues and pheromones, and potential applications to population management. The critical role of olfaction in mediating the sea lamprey life cycle is evident by a well-developed olfactory system. Sea lamprey use chemical cues and pheromones to identify productive spawning habitat, coordinate spawning behaviors, and avoid risk. Manipulation of olfactory biology offers opportunities for management of populations in the Laurentian Great Lakes, where the sea lamprey is a destructive invader. We suggest that the sea lamprey is a broadly useful organism with which to study vertebrate olfaction because of its simple but well-developed olfactory organ, the dominant role of olfaction in guiding behaviors during reproduction, and the direct implications for vertebrate pest management
Ballistic nanofriction
Sliding parts in nanosystems such as Nano ElectroMechanical Systems (NEMS)
and nanomotors, increasingly involve large speeds, and rotations as well as
translations of the moving surfaces; yet, the physics of high speed nanoscale
friction is so far unexplored. Here, by simulating the motion of drifting and
of kicked Au clusters on graphite - a workhorse system of experimental
relevance -- we demonstrate and characterize a novel "ballistic" friction
regime at high speed, separate from drift at low speed. The temperature
dependence of the cluster slip distance and time, measuring friction, is
opposite in these two regimes, consistent with theory. Crucial to both regimes
is the interplay of rotations and translations, shown to be correlated in slow
drift but anticorrelated in fast sliding. Despite these differences, we find
the velocity dependence of ballistic friction to be, like drift, viscous
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