Aluminum Bands Research Articles

Maximally localized Wannier functions within the (L)APW+LO method

We present a robust algorithm that computes (maximally localized) Wannier functions (WFs) without the need of providing an initial guess. Instead, a suitable starting point is constructed automatically from so-called local orbitals which are fundamental building blocks of the basis set within (linearized) augmented planewave methods. Our approach is applied to a vast variety of materials such as metals, bulk and low-dimensional semiconductors, and complex inorganic-organic hybrid interfaces. For the interpolation of electronic single-particle energies, an accuracy in the meV range can be easily achieved. We exemplify the capabilities of our method by the calculation of the joint density of states in aluminum, (generalized) Kohn-Sham and quasi-particle band structures in various semiconductors, and the electronic structure of $\beta$-Ga$_2$O$_3$, including electron and hole effective masses.

Band Wear and Effects on Recovery and Survival Estimates of Diving Ducks

ABSTRACTWildlife biologists commonly use marked individuals to estimate population size and vital rates. If markers are lost or become too illegible to be reported (which we define as functional loss), population size and vital rates derived from marked individuals could be biased. We double‐banded 4,990 lesser scaup (Aythya affinis) and 1,429 redheads (A. americana) with a traditionally used band made of aluminum, plus another band made of incoloy designed to be more resistant to wear. Banding took place at 10 late‐summer banding stations in the northcentral United States and Canada during 2009 and 2010 and during spring at Pool 19 on the Mississippi River, Iowa, USA, during 2009–2011. We then examined bands recovered from hunter‐shot birds to assess wear of paired bands. We also conducted band‐recovery analyses to test for differences in band retention and reporting rates between birds banded with aluminum versus hard metal bands. Band wear assessments indicated that incoloy bands lost zero mass over time and showed no effects of wear. Although no bands were lost, aluminum bands showed significant mass loss and wear over time. For double‐banded lesser scaup recovered in their fourth year after banding, 71.9% of aluminum bands had contact information that was completely unreadable, compared with only 12.5% for those worn by redheads. Based on our recent double‐band recovery data, up to 34% of lesser scaup bands would be recovered during the fifth through eighth hunting seasons of band wear. Band wear affected estimated recovery rates of both species, with stronger effects in lesser scaup. Our results indicate that use of aluminum bands resulted in a substantial loss of information; thus, banders should only use bands made of hard metal alloys (e.g., incoloy or stainless steel), and discontinue all use of aluminum bands for these species and other diving ducks with sparse recovery data. Future demographic analyses using banding data for species with excessive band wear and low numbers of band‐recoveries should account for band type and functional band loss. © 2020 The Wildlife Society.

Foraging of vampire bats ( Desmodus rotundus ) in Atlantic wet lowland Costa Rica

Extensive observations of the foraging activity of vampire bats (Desmodus rotundus) were conducted for eleven successive months at one locality in Atlantic wet lowland Costa Rica. This study period included parts of two wet seasons and one entire dry season. Data were obtained on nightly departures and returns of individual vampires at two roosting sites in order to estimate the amount of time spent away from roosts during the wet and dry seasons. Several individuals from these roots were marked (using different colored aluminum bands for different roosts) and nightly data were also obtained on their Occurrence, along with many unmarked individuals, attaching themselves to cattle (prey) inhabiting three nearby pastures. From these two series of observations, it was found that (i) vampires exploit local cattle populations for blood; (ii) vampires invariably return to the same roosts every night after foraging; (iii) vampires spend more time attached to their prey animals during the dry season than they do during the wet season, and (iv) presumably more blood is actually ingested during the dry season. A brief study of homing ability demonstrated that vampires can return to their original roosting sites from as far away as 10 to 18 miles.

Evaluation of leg banding and attachment of radio‐transmitters on ring‐necked pheasant chicks

Marking birds is a vital tool for determining survival, habitat‐use patterns, and movements. For galliform species, metal leg bands and radio‐transmitters are widely used marking techniques. While commonly used on adult birds, leg banding and radio‐marking of galliform chicks are not commonly employed. During a two‐year study to evaluate survival, dispersal, and habitat‐use of released four‐week old ring‐necked pheasants Phasianus colchicus, we sought to mark chicks in a manner that allowed us to track them post‐release and recognize them if harvested as adults. Our objectives were to evaluate the efficacy of four banding techniques: 1) standard bands for adult ring‐necked pheasants [no. 6 aluminum butt‐end bands], 2) colored plastic spiral leg bands commonly used for banding poultry, 3) no. 6 bands and plastic spiral leg bands to prevent the aluminum bands from slipping off, and 4) cotton‐filled no. 6 bands to prevent bands from slipping off and allow growth of the tarsus. We also evaluated two radio‐transmitter attachment methods: gluing or suturing transmitters on the back of four‐week‐old chicks. The no. 6 bands did not stay attached to the birds due to the bands being too large, and plastic spiral bands commonly caused constriction of the legs, possibly crippling birds. However, using cotton filled leg‐bands was a reliable method for marking pheasant chicks. Although gluing has been used successfully as a radio‐transmitter attachment method in other studies, in our study it largely failed given that few radio‐transmitters remained attached beyond two days. Suturing was an effective method (90% of the transmitters remained attached until death or expected life of the battery) for attaching radio‐transmitters to ring‐necked pheasant chicks. Our field study has revealed promising approaches and we suggest that a captive study should now evaluate the possible sub‐lethal effects (e.g. growth rates, body condition, transmitter retention times) of these attachment methods.

Band-related Foot Loss Does Not Prevent Successful Return and Reproduction in the Ovenbird (Seiurus aurocapilla)

In spite of recent developments in tracking technology, leg bands are still the main marking method in songbird population studies. Yet, band-related injury rates and the effects of such injuries on survival and reproductive success have rarely been documented in songbirds. Over a 9-year period, we banded 525 male Ovenbirds using a numbered aluminum band and three celluloid color bands. Of these, 322 individuals returned to our study area in at least one of the subsequent years, including four males (1.2%) missing a foot. In all cases, foot loss occurred 2–3 years after banding, suggesting indirect effects of bands rather than injuries sustained at the time of capture or banding. Among returning individuals, 91 were recaptured and only one had noticeable leg injuries that did not result in foot loss. Three of the four males missing a foot were able to fledge young, one of which produced young during two successive breeding seasons. The fact that injured males could hold territories overlapping their previous one and produce young suggests that they could forage efficiently. Although leg injuries may carry a cost over the longer term, two of the four injured males were re-sighted in our study area the year following the first observation of foot loss. Our results, along with those of other studies, suggest that the benefits of bird banding greatly outweigh the costs associated with potential injuries, at least in this ground-foraging forest songbird.

Readability of Anodized Aluminum Bands Versus Plastic Darvic Bands on Striated Caracaras in the Falkland Islands (Malvinas)

Readability of Anodized Aluminum Bands Versus Plastic Darvic Bands on Striated Caracaras in the Falkland Islands (Malvinas)

Retention of Riveted Aluminum Leg Bands by Wild Turkeys

Abstract In order for mark–recapture models to provide unbiased estimates of population parameters, it is critical that uniquely identifying tags or marks are not lost. We double-banded male and female wild turkeys with aluminum rivet bands and estimated the probability that a bird would be recovered with both bands <1–225 wk since banding (mean = 51.2 wk, SD = 44.0). We found that 100% of females (n = 37) were recovered with both bands. For males, we recovered 6 of 188 turkeys missing a rivet band for a retention probability of 0.984 (95% CI = 0.96–0.99). If male turkeys are double-banded with rivet bands the probability of recovering a turkey without any marks is <0.001. We failed to detect a change in band retention over time or differences between adults and juveniles. Given the low cost and high retention rates of rivet aluminum bands, we believe they are an effective marking technique for wild turkeys and, for most studies, will minimize any concern about the assumption that marks are not lost.

Microstructure Characteristic of Adiabatic Shear Bands for Aluminum Matrix Composites Compressed With High Strain Rates

In this paper, the novel transformed bands in adiabatic shear bands (ASBs) were researched which was characterized as melting or solid to liquid phase transformation. By split Hopkinson pressure bar (SHPB), optical microscope (OM) and scanning electron microscope (SEM), microstructure characteristic in the transformed bands at varied strain rates were observed. From the experimental results, it was found that molten aluminum bands and aluminum balls agglomeration, which called transformed bands, were found on the shearing surface for 55%TiB2/Al composites compressed at strain rates of 1~2×103 s -1 . It was concluded that there were the molten aluminium alloy and the molten aluminium particles on the shear flat surface oriented at an angle approximately 45°to the compression axis, which was transformed band. It was formed due to aluminium alloy melt at high temperature and solidified sharply by analysis. The formation of transformed bands was ascribed to adiabatic temperature rise, which caused aluminum alloy matrix softened and molten. The adiabatic temperature rise was 800-900K by caculation. The local high temperature led to the formation of the molten aluminium particles whose diameter was 1-3µm on the adiabatic shear flat surface. With the rapid convergence of molten aluminium particles and growing up, the adiabatic shear band was finally formed.

Rapid Treatment of Waist Pain by Nanoscale Electric Stimulation

The primary purpose of the study was to examine the ability of thin aluminum and copper bands to treat difficulties in moving, such as walking, standing and sitting, due to waist pain. The mechanism behind this therapy is a very weak nanoscale electrical stimulation caused by the electric current flow between aluminum and copper due to a difference in ionization tendency and electronegativity. The bands were firmly attached at the specified area, which was carefully selected based on the nerve connection of the human body. Prompt improvement in those having moving difficulties could be observed. More clinical trials are being conducted to analyze the rapid effect of nanoelectric current on the treatment of pain.

An experimental assessment of shotgun discharge on aluminum legband retention

AbstractAlthough metal legbands have been an important scientific tool, their use for estimation of harvest and survival relies on samples of dead birds harvested by hunters using shotguns. We hypothesized that the force of steel pellets discharged from a shotgun, within the range of conditions normally experienced by goose hunters, was sufficient to reduce probability of band retention. We conducted 8 experimental trials to estimate retention per round fired at aluminum bands normally applied to arctic‐nesting geese in relation to effects of 1) target range (20 m vs. 40 m), 2) steel pellet size (4.57 mm [BB] vs. 3.81 mm [number 2]), 3) cartridge size (76.2 mm [3 in.] vs. 69.9 mm [2.75 in.]), and 4) number of rounds fired (up to 25). There was nearly complete band retention (0.999/round) at 40 m regardless of shot size or shell size used. Retention per round fired at 20 m declined to between 0.984 and 0.987 for number 2 shot and between 0.968 and 0.974 for BB shot. Our conclusions apply to unworn bands, so we recommend further simulations to assess how retention may change with age of bands as they erode or corrode on free‐ranging geese. Bias in estimates associated with loss of older bands from shotgun discharge could be adjusted if bias is estimated as done in this article. © 2011 The Wildlife Society.

Evaluation of Total Body Electrical Conductivity to Estimate Body Composition of a Small Mammal

ABSTRACT The ability to measure body composition is critical for studying the physiological ecology of animals. This is particularly true for small mammals that have a high metabolic rate. We evaluated a nondestructive method of body composition analysis that would allow accurate assessment of body fat, body water, and lean mass. We used total body electrical conductivity (TOBEC) to estimate body composition in the little brown myotis (Myotis lucifugus). In a sample of 46 individuals, TOBEC was both accurate and precise in estimating total body water and lean mass but was less effective at estimating total body fat. Mass‐independent or whole‐body compartments (i.e., total body water, total body fat, lean dry mass, and lean body mass) were more accurately estimated than mass‐dependent or mass‐specific body composition compartments (i.e., water content, fat index, and % lean dry mass). The TOBEC measurements we made using an SA‐3000 analyzer were influenced by extremes in body temperature, as well as by aluminum and incoloy wing bands. Our study also presents a new method of restraint especially suited for small mammals and birds that increases precision of TOBEC measurements. This study shows that TOBEC is a potentially valuable tool for studying changes in body composition of small mammals and may provide insight into the physiological impacts of various life history stages such as postnatal growth, reproduction, and hibernation.

Characterization and Management of Postoperative Hemorrhage Following Upper Retroperitoneal Laparoscopic Surgery

Surgical paradigms may change in the era of laparoscopic surgery. We evaluated a conservative nonsurgical approach to postoperative hemorrhage following laparoscopic upper retroperitoneal surgery as opposed to the more traditional strategy of reexploring the surgical site. In 911 laparoscopic procedures performed in 8 years we retrospectively identified risk factors and characterized treatment for postoperative hemorrhage. We considered postoperative hemorrhage to be present when postoperative transfusion was required that could not be accounted for by operative blood loss or another definable cause outside of the surgical field. Red blood cell transfusion was required after 53 procedures (5.8%), of which 34 (3.7%) were done for postoperative hemorrhage. Postoperative hemorrhage occurred only after nephrectomy in 3.3% of cases, after partial nephrectomy in 9.9% and after adrenalectomy in 5.4%. Multivariate analysis revealed a significant association of postoperative hemorrhage with patient age and American Society of Anesthesiologists score (preoperative factors), operative time and splenic injury (intraoperative factors), and gastrointestinal complications and prolonged hospitalization (postoperative factors). Postoperative hemorrhage increased mean hospitalization from 2.5 to 6.4 days. No significant differences in post-hospital recovery were associated with postoperative hemorrhage. Only 4 of the 34 patients (12%) required surgical management of postoperative hemorrhage. All other cases were conservatively managed. Outcome after surgical and conservative management did not differ except postoperative renal complications tended to be more common in the former cases (50% vs 7%). Most patients with hemorrhage following laparoscopic upper retroperitoneal surgery can be treated with conservative nonsurgical interventions.

Novel anodized aluminum bands cause leg injuries in Piping Plovers

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Wear and Opening as Sources of Band Loss in the White Stork

Butt-end and lock-on aluminum band loss and wear were studied in the White Stork (Ciconia ciconia) banded in Spain. The risk of loss of butt-end bands increased from 0% to 85% in bands of 0 to 12 years. However, no loss occurred when storks were banded on the tibia rather than in the tarsus. Lock-on metal bands showed a low band loss rate throughout. The results indicated that band loss was mainly caused by the band opening, probably because of frequent contact with mud and water on the tarsus. Aluminum bands should be completely discarded to avoid important biases in analyses of population dynamics, dispersal and survival of storks and other groups. This is currently already done in many banding schemes, but should be applied more generally worldwide.

A technique to produce aluminum color bands for avian research

We developed a technique to produce metal (aluminum) color bands, in response to concerns about leg injuries caused by celluloid-plastic color bands applied to Willow Flycatchers (Empidonax traillii). The technique involves color-anodized aluminum bands (unnumbered blanks and federal numbered bands), with auto pin-striping tape and flexible epoxy sealant, to create a variety of solid, half- and triple-split colors. This allows for hundreds of unique, high-contrast color combinations. During six consecutive years of application, these colored metal bands have resisted color fade compared to conventional celluloid-plastic bands, and have reduced leg injuries in the flycatcher. Although not necessarily warranted for all color-banding studies, these metal bands may provide a lower-impact option for studies of species known to be impacted by plastic color bands.

Intelligent location of two simultaneously active acoustic emission sources

Acoustic emission (AE) analysis is used for characterization and location of developing defects in materials. The location of AE on complicated aircraft frame structures is a difficult problem of non-destructive testing. This article describes an intelligent AE source locator which comprises a sensor antenna and a general regression neural network, which solves the location problem based on learning from examples. The location accuracy achieved by the intelligent locator is comparable to that obtained by the conventional triangulation method, while the applicability of the intelligent locator is more general since analysis of sonic ray paths is avoided. AE sources often generate a mixture of various statistically independent signals. A difficult problem of AE analysis is separation and characterization of signal components when the signals from various sources and the mode of mixing are unknown. Recently, blind source separation (BSS) by independent component analysis (ICA) has been used to solve these problems. The purpose of this paper is to demonstrate the applicability of ICA to separate and locate two independent simultaneously active AE sources on an aluminum band specimen. The method is promising for non-destructive testing of aircraft frame structures by acoustic emission analysis.

Production and Metrology of Cylindrical Inertial Confinement Fusion Targets with Sinusoidal Perturbations

Shock waves generated during inertial confinement fusion implosions propagate toward the center of the capsule encountering interfaces between materials with different densities, such as between the ablator and the DT fuel. These interactions are hydrodynamically unstable and the resulting instability causes mixing of the materials at the interface, which is predicted to have detrimental effects on fusion burn. In this experiment, the growth of a single-mode perturbation machined into a radiographically opaque marker layer, driven by a strong shock, is measured during a cylindrically symmetric implosion. These measurements are used to validate simulations and theories of the complex hydrodynamics. Since any perturbation on the marker layer surface will lead to instability growth, precise knowledge of the initial conditions is critical. The targets used in this experiment have up to a 3.0-μm-amplitude, mode 28 (θ = 98 μm) sinusoidal perturbation machined into a 438-μm-outerradius aluminum band with a nominal thickness of 8 μm. The perturbations were machined using a fast-tool servo [B. JARED and T. A. DOW, Precision Engineering Center Annual Report, North Carolina State University, Raleigh NC, p. 123 (1996)] and were metrologized using a linear variable differential transformer [FRANK J. OLIVER, Practical Instrumentation Tranducers, p. 42-45, Hayden Book Company (1971)]. In this paper, the importance of metrology is discussed and is shown to be critical to the interpretation of experimental results.

Intelligent location of two simultaneously active acoustic emission sources: Part II

In Part I, an intelligent acoustic emission (AE) locator is described while the Part II discusses a blind source separation, time delay estimation and location of two continuous AE sources. AE analysis is used for characterization and location of developing defects in materials. AE sources often generate a mixture of various statistically independent signals. A difficult problem of AE analysis is a separation and characterization of signal components when the signals from various sources and the mode of mixing are unknown. Recently, blind source separation (BSS) by independent component analysis (ICA) has been used to solve these problems. The purpose of this paper is to demonstrate the applicability of ICA to locate two independent simultaneously active AE sources on an aluminum band specimen. The method is promising for non‐destructive testing of aircraft frame structures by AE analysis.

Location of acoustic emission sources generated by air flow

The location of continuous acoustic emission sources is a difficult problem of non-destructive testing. This article describes one-dimensional location of continuous acoustic emission sources by using an intelligent locator. The intelligent locator solves a location problem based on learning from examples. To verify whether continuous acoustic emission caused by leakage air flow can be located accurately by the intelligent locator, an experiment on a thin aluminum band was performed. Results show that it is possible to determine an accurate location by using a combination of a cross-correlation function with an appropriate bandpass filter. By using this combination, discrete and continuous acoustic emission sources can be located by using discrete acoustic emission sources for locator learning.

Theoretical investigations of NMR chemical shieldings on the AlPON catalyst system

Using molecular cluster models we present a theoretical ab initio study of the 27 Al and 31 P nuclear magnetic resonance (NMR) chemical shieldings aimed at obtaining short-range structural information on the aluminophosphate oxynitride (AlPON) catalyst system. We have employed orthophosphate-like molecular models with P/Al ratio equal to one and varying N/O ratios to simulate the experimentally obtained compositions. The computed NMR chemical shieldings reproduce quantitatively the observed features in the 31 P magic angle spinning NMR (MAS-NMR) spectra and permit the explanation of these modifications in terms of a progressive and preferential nitridation on the first coordination shell of the phosphorus atom leading to a mixture of [PO x N 4− x ] units in the solid. The comparison of 27 Al isotropic chemical shieldings and the experimental spectra allow us to conclude that N/O substitution does not happen in the first coordination shell of aluminum atoms. The experimentally observed broadening of the tetrahedral aluminum band can be explained by a nitridation of aluminum environment, but not by a nitridation of its first coordination shell.