Spacing effects on seedlings of northern red oak and yellow-poplar

Seedlings of northern red oak (Quercus rubra L.) and yellow-poplar (Liriodendron tulipifera L.) were grown at spacings of 10.8/m2 (1 per square foot), 26.9/ m2 (2.5 per square foot), and 53.8/m2 (5 per square foot) for 2 years. Spacing had no significant effect on first-year growth of either species, but increasing density significantly reduced second-year growth. Compared to the 53.8/m2 spacing, 2-year-old seedlings of northern red oak were 3 times larger at 10.8/m 2, and 2-year-old seedlings of yellow-poplar were 4.8 times larger at 10.8/m2

A negative mass theorem for surfaces of positive genus

We define the "sum of squares of the wavelengths" of a Riemannian surface (M,g) to be the regularized trace of the inverse of the Laplacian. We normalize by scaling and adding a constant, to obtain a "mass", which is scale invariant and vanishes at the round sphere. This is an anlaog for closed surfaces of the ADM mass from general relativity. We show that if M has positive genus then on each conformal class, the mass attains a negative minimum. For the minimizing metric, there is a sharp logarithmic Hardy-Littlewood-Sobolev inequality and a Moser-Trudinger-Onofri type inequality.Comment: 8 page

Oxygen and nitrogen cycling in the northeast Pacific – Simulations and observations at Station Papa in 2003/2004

A long-term air-sea exchange mooring has been maintained in the North Pacific near Ocean Station Papa (OSP, 145W, 50N) since September 2002 as part of the Canadian Surface Ocean Lower Atmosphere Study (C-SOLAS). The mooring provides a new long-term data set for gas measurements. In addition to Conductivity, Temperature and Depth (CTD) recorders at two depths, the mooring is equipped with ProOceanus Gas Tension Devices (GTDs) measuring the total gas pressure at four different depths, two oxygen sensors, two fluorometers for chlorophyll estimates, and an upward-looking 200 kHz echo-sounder for bubble measurements. Chlorophyll data have been added using SeaWiFS imagery and occasional bottle casts. Data collected from June 2003 to June 2004 are compared with simulations from a 1-D coupled atmosphere-ocean-biogeochemical model. The coupled model consists of an atmospheric Single Column Model (SCM), based on the CCCma AGCM (Canadian Centre for Climate Modelling and Analysis-Atmospheric General Circulation Model), the General Ocean Turbulence Model (GOTM) and a 7-component ecosystem model embedded in GOTM. The ecosystem model also includes oxygen, nitrogen, carbon, and silica cycling. The study focuses on simulated and observed N2 and O2 variability. The comparison of these gases allows for separation of physical and biological processes; which can then be evaluated in more detail with the aid of model simulations. The model also tests different parameterizations for saturation and gas exchange, including a formulation for gas injection via bubbles, which affects gas concentrations within the whole mixed layer. For most of the time the model shows good agreement with observations. However, in summer 2003 the observations reveal a strong oxygen and chlorophyll event, which is not reproduced in the standard model run. A weaker signal is seen in May 2004. OSP is a High Nutrient Low Chlorophyll (HNLC) region, limited by the micronutrient iron. Increases in usually low chlorophyll values occur occasionally due to natural iron enrichment (dust deposition, eddy transport, below surface layer transport). Although limitations of 1-D modeling become apparent here, an assumed input of iron in the model explains the differences between simulated and observed oxygen and chlorophyll maxima. The model provides information on the strength and duration of potential iron contribution. No obvious dust events or eddy traverses to supply iron were recorded during this time period. An alternative explanation is entrainment from deeper waters, where occasional iron enrichment is known to occur due to off-shelf transport via eddies or recirculation from the Alaskan shelf

Eye enucleation and exenteration in -cattle: a retrospective study of 38 cases (2013-2020).

INTRODUCTION The study aimed to describe clinical indications for eye enucleation and exenteration, the occurrence of complications and long-term outcome in cattle, and examine owners' attitude towards enucleation and exenteration and their satisfaction with the surgical outcome. Medical records from the two veterinary teaching hospitals in Switzerland were reviewed to identify cattle that underwent unilateral enucleation or exenteration between January 2013 and December 2020. Data extracted included medical history, ocular examination, clinical diagnosis, surgical procedure including anesthesia, suture material and pattern used, complications, and treatment thereof. Long-term follow-up was evaluated via national animal database inquiries to determine survival time and via owners' interviews with the use of a standardized questionnaire that included questions regarding the occurrence of complications and reason for culling, production performances and perceived quality of life after surgery, concerns, factors affecting the decision to proceed with surgery, and general satisfaction with the outcome. Descriptive statistics, Fisher's exact tests and unpaired t-test were used to summarize the data and assess association between variables. Association was considered significant if p < 0,05. Thirty-eight cases were identified, with a median age of 5 years. More than half of the cases (55,3 %) were diagnosed with non-neoplastic ocular lesions represented by severe trauma with loss of globe content, globe rupture with history of infectious keratoconjunctivitis or hypopyon, or congenital malformations. The remaining cases were diagnosed with neoplastic lesions, including ocular squamous cell carcinoma (OSCC), melanoma, or sarcoma. Complications following surgery were reported in 29 % of cases and included postoperative infection and recurrence of OSCC. There was no significant association between ocular diagnosis and the occurrence of postoperative complications or survival time. Surgery did not seem to influence the animals' postoperative production performance or the perceived quality of life. Most owners (92 %) were satisfied with the surgical outcome. The occurrence of postoperative complications leading to increased overall costs and culling was the main reason for lower owner satisfaction

Nature of the constant factor in the relation between radial breathing mode frequency and tube diameter for single-wall carbon nanotubes

Resonance Raman scattering is used to determine the radial breathing mode (RBM) frequency (ωRBM) dependence on tube diameter (dt) for single-wall carbon nanotubes (SWNTs). We establish experimentally the ωRBM=227.0/dt as the fundamental relation for pristine SWNTs. All the other RBM values found in the literature can be explained by an upshift in frequency due mostly to van der Waals interaction between SWNTs and environment

LArPix: Demonstration of low-power 3D pixelated charge readout for liquid argon time projection chambers

We report the demonstration of a low-power pixelated readout system designed for three-dimensional ionization charge detection and digital readout of liquid argon time projection chambers (LArTPCs). Unambiguous 3D charge readout was achieved using a custom-designed system-on-a-chip ASIC (LArPix) to uniquely instrument each pad in a pixelated array of charge-collection pads. The LArPix ASIC, manufactured in 180 nm bulk CMOS, provides 32 channels of charge-sensitive amplification with self-triggered digitization and multiplexed readout at temperatures from 80 K to 300 K. Using an 832-channel LArPix-based readout system with 3 mm spacing between pads, we demonstrated low-noise ($<$500 e$^-$ RMS equivalent noise charge) and very low-power ($<$100 $\mu$W/channel) ionization signal detection and readout. The readout was used to successfully measure the three-dimensional ionization distributions of cosmic rays passing through a LArTPC, free from the ambiguities of existing projective techniques. The system design relies on standard printed circuit board manufacturing techniques, enabling scalable and low-cost production of large-area readout systems using common commercial facilities. This demonstration overcomes a critical technical obstacle for operation of LArTPCs in high-occupancy environments, such as the near detector site of the Deep Underground Neutrino Experiment (DUNE).Comment: 19 pages, 10 figures, 1 ancillary animation. V3 includes minor revisions based on referee comment