Some Factors Affecting the Nest-Cleaning Behavior of Honey Bees (Apis mellifera)

Glass-paned observation hives were used to study the behavior of nestcleaning in American Foulbrood-resistant honey bees. Transplanted-dead brood in comb inserts was used to determine the rate of removal of dead brood. Dead brood located within the brood nest was removed faster than dead brood located in other areas. Strong nectar flow appeared to exert a positive influence on the rate of removal of dead brood. Comparisons made between the responses of honey bees toward brood killed by American Foulbrood and brood killed by hydrogen cyanide showed inconsistencies that indicate the possibility of unknown environmental factors

Inconsistent black hole kick estimates from gravitational-wave models

The accuracy of gravitational-wave models of compact binaries has traditionally been addressed by the mismatch between the model and numerical-relativity simulations. This is a measure of the overall agreement between the two waveforms. However, the largest modelling error typically appears in the strong-field merger regime and may affect subdominant signal harmonics more strongly. These inaccuracies are often not well characterised by the mismatch. We explore the use of a complementary, physically motivated tool to investigate the accuracy of gravitational-wave harmonics in waveform models: the remnant's recoil, or kick velocity. Asymmetric binary mergers produce remnants with significant recoil, encoded by subtle imprints in the gravitational-wave signal. The kick estimate is highly sensitive to the intrinsic inaccuracies of the modelled gravitational-wave harmonics during the strongly relativistic merger regime. Here we investigate the accuracy of the higher harmonics in four state-of-the-art waveform models of binary black holes. We find that the SEOBNRv4HM_ROM, IMRPhenomHM, IMRPhenomXHM and NRHybSur3dq8 models are not consistent in their kick predictions. Our results enable us to identify regions in the parameter space where the models require further improvement and support the use of the kick estimate to investigate waveform systematics. We discuss how numerical-relativity kick estimates could be used to calibrate waveform models further, proposing the first steps towards kick-based gravitational-wave tuning

Nanoscale magnetic structure of ferromagnet/antiferromagnet manganite multilayers

Polarized Neutron Reflectometry and magnetometry measurements have been used to obtain a comprehensive picture of the magnetic structure of a series of La{2/3}Sr{1/3}MnO{3}/Pr{2/3}Ca{1/3}MnO{3} (LSMO/PCMO) superlattices, with varying thickness of the antiferromagnetic (AFM) PCMO layers (0<=t_A<=7.6 nm). While LSMO presents a few magnetically frustrated monolayers at the interfaces with PCMO, in the latter a magnetic contribution due to FM inclusions within the AFM matrix was found to be maximized at t_A~3 nm. This enhancement of the FM moment occurs at the matching between layer thickness and cluster size, where the FM clusters would find the optimal strain conditions to be accommodated within the "non-FM" material. These results have important implications for tuning phase separation via the explicit control of strain.Comment: 4 pages, submitted to PR

Black-hole kicks: a tool to measure the accuracy of gravitational-wave models

Asymmetric binary systems radiate linear momentum through gravitational waves, leading to the recoil of the merger remnant. Black-hole kicks have attracted much attention because of their astrophysical implications. However, little information can be extracted from the observations made by LIGO and Virgo so far. In this work, we discuss how the gravitational recoil, an effect that is encoded in the gravitational signal, can be used to test the accuracy of waveform models. Gravitational-wave models of merging binary systems have become fundamental to detect potential signals and infer the parameters of observed sources. But, as the interferometers' sensitivity is enhanced in current and future detectors, gravitational waveform models will have to be further improved. We find that the kick is highly sensitive to waveform inaccuracies and can therefore be a useful diagnostic test. Furthermore, we observe that current higher-mode waveform models are not consistent in their kick predictions. For this reason, we discuss whether measuring and improving waveform accuracy can, in turn, allow us to extract meaningful information about the kick in future observations

An Electrophoretic Study of Caecal Proteins of Clinostomum marginatum (Trematoda)

Whole-worm extracts of Clinostomum marginatum were subjected to polyacrylamide gel electrophoresis. Gels of early stage metacercariae, late-stage metacercariae and adult worms contained 26,24, and 27 protein bands respectively. The protein band patterns of the three stages were similar except for 1) a hemoglobin band in gels of adult extracts and 2) a large increase in the quantity of four anodic bands of late-stage gels. The proteins constituting these four bands were present in the caecal contents of late-stage metacercariae . These same proteins were also found in metacercarial cysts as part of an exuded material left behind by the fluke after excystment

Twin Texts and Technology: Enhancing Algebra Instruction for Elementary Teachers

Introduction: Algebra is often thought of as a course taken in high school, not a part of mathematics instruction in the elementary grades. In reality, algebra is the study of mathematics concerning structure, relations, and quantity and justifying those relationships (Blanton, 2008)