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Hybrid pixel detectors have become indispensable at synchrotron and X-ray free-electron laser facilities thanks to their large dynamic range, high frame rate, low noise, and large area. However, at energies below 3 keV, the detector performance is often limited because of the poor quantum efficiency of the sensor and the difficulty in achieving single-photon resolution due to the low signal-to-noise ratio. In this paper, we address the quantum efficiency of silicon sensors by refining the design of the entrance window, mainly by passivating the silicon surface and optimizing the dopant profile of the n + region. We present the measurement of the quantum efficiency in the soft X-ray energy range for silicon sensors with several process variations in the fabrication of planar sensors with thin entrance windows. The quantum efficiency for 250 eV photons is increased from almost 0.5% for a standard sensor to up to 62% as a consequence of these developments, comparable to the quantum efficiency of backside-illuminated scientific CMOS sensors. Finally, we discuss the influence of the various process parameters on quantum efficiency and present a strategy for further improvement.

The Community Research Liaison Model (CRLM) is a novel model to facilitate community-engaged research (CEnR) and community-academic research partnerships focused on health priorities identified by the community. This model, informed by the Principles of Community Engagement, builds trust among rural communities and expands capacity for community and investigator-initiated research. We describe the CRLM development process and how it is operationalized today. We followed a multi-phase process to design and implement a community engagement model that could be replicated. The resulting CRLM moves community-academic research collaborations from objectives to outputs using a conceptual framework that specifies our guiding principles, objectives, and actions to facilitate the objectives (i.e., capacity, motivations, and partners), and outputs. The CRLM has been fully implemented across Oregon. Six Community Research Liaisons collectively support 18 predominantly rural Oregon counties. Since 2017, the liaison team has engaged with communities on nearly 300 community projects. The CRLM has been successful in facilitating CEnR and community-academic research partnerships. The model has always existed on a dynamic foundation and continues to be responsive to the lessons learned by the community and researchers. The model is expanding across Oregon as an equitable approach to addressing health disparities across the state., Competing Interests: Authors have disclosed that they do not have any financial conflicts of interest., (© The Author(s) 2023.)

Chromium compensated GaAs or GaAs:Cr sensors provided by the Tomsk State University (Russia) were characterized using the low noise, charge integrating readout chip JUNGFRAU with a pixel pitch of 75 × 75 µm 2 regarding its application as an X-ray detector at synchrotrons sources or FELs. Sensor properties such as dark current, resistivity, noise performance, spectral resolution capability and charge transport properties were measured and compared with results from a previous batch of GaAs:Cr sensors which were produced from wafers obtained from a different supplier. The properties of the sample from the later batch of sensors from 2017 show a resistivity of 1.69 × 10 9 Ω/cm, which is 47% higher compared to the previous batch from 2016. Moreover, its noise performance is 14% lower with a value of (101.65 ± 0.04) e - ENC and the resolution of a monochromatic 60 keV photo peak is significantly improved by 38% to a FWHM of 4.3%. Likely, this is due to improvements in charge collection, lower noise, and more homogeneous effective pixel size. In a previous work, a hole lifetime of 1.4 ns for GaAs:Cr sensors was determined for the sensors of the 2016 sensor batch, explaining the so-called "crater effect" which describes the occurrence of negative signals in the pixels around a pixel with a photon hit due to the missing hole contribution to the overall signal causing an incomplete signal induction. In this publication, the "crater effect" is further elaborated by measuring GaAs:Cr sensors using the sensors from 2017. The hole lifetime of these sensors was 2.5 ns. A focused photon beam was used to illuminate well defined positions along the pixels in order to corroborate the findings from the previous work and to further characterize the consequences of the "crater effect" on the detector operation.

Recent advances in segmented low-gain avalanche detectors (LGADs) make them promising for the position-sensitive detection of low-energy X-ray photons thanks to their internal gain. LGAD microstrip sensors fabricated by Fondazione Bruno Kessler have been investigated using X-rays with both charge-integrating and single-photon-counting readout chips developed at the Paul Scherrer Institut. In this work it is shown that the charge multiplication occurring in the sensor allows the detection of X-rays with improved signal-to-noise ratio in comparison with standard silicon sensors. The application in the tender X-ray energy range is demonstrated by the detection of the sulfur K α and K β lines (2.3 and 2.46 keV) in an energy-dispersive fluorescence spectrometer at the Swiss Light Source. Although further improvements in the segmentation and in the quantum efficiency at low energy are still necessary, this work paves the way for the development of single-photon-counting detectors in the soft X-ray energy range.

EIGER is a single-photon-counting hybrid pixel detector developed at the Paul Scherrer Institut, Switzerland. It is designed for applications at synchrotron light sources with photon energies above 5 keV. Features of EIGER include a small pixel size (75 µm × 75 µm), a high frame rate (up to 23 kHz), a small dead-time between frames (down to 3 µs) and a dynamic range up to 32-bit. In this article, the use of EIGER as a detector for electrons in low-energy electron microscopy (LEEM) and photoemission electron microscopy (PEEM) is reported. It is demonstrated that, with only a minimal modification to the sensitive part of the detector, EIGER is able to detect electrons emitted or reflected by the sample and accelerated to 8-20 keV. The imaging capabilities are shown to be superior to the standard microchannel plate detector for these types of applications. This is due to the much higher signal-to-noise ratio, better homogeneity and improved dynamic range. In addition, the operation of the EIGER detector is not affected by radiation damage from electrons in the present energy range and guarantees more stable performance over time. To benchmark the detector capabilities, LEEM experiments are performed on selected surfaces and the magnetic and electronic properties of individual iron nanoparticles with sizes ranging from 8 to 22 nm are detected using the PEEM endstation at the Surface/Interface Microscopy (SIM) beamline of the Swiss Light Source.

MÖNCH is a 25 µm-pitch charge-integrating detector aimed at exploring the limits of current hybrid silicon detector technology. The small pixel size makes it ideal for high-resolution imaging. With an electronic noise of about 110 eV r.m.s., it opens new perspectives for many synchrotron applications where currently the detector is the limiting factor, e.g. inelastic X-ray scattering, Laue diffraction and soft X-ray or high-resolution color imaging. Due to the small pixel pitch, the charge cloud generated by absorbed X-rays is shared between neighboring pixels for most of the photons. Therefore, at low photon fluxes, interpolation algorithms can be applied to determine the absorption position of each photon with a resolution of the order of 1 µm. In this work, the characterization results of one of the MÖNCH prototypes are presented under low-flux conditions. A custom interpolation algorithm is described and applied to the data to obtain high-resolution images. Images obtained in grating interferometry experiments without the use of the absorption grating G 2 are shown and discussed. Perspectives for the future developments of the MÖNCH detector are also presented.

Measuring the thermal conditions of aquatic reptiles with temperature dataloggers is a cost-effective way to study their behavior and habitat use. Temperature dataloggers are a particularly useful and informative approach to studying organisms such as the estuarine diamondback terrapin (Malaclemys terrapin) that inhabits a dynamic environment often inaccessible to researchers. We used carapace-mounted dataloggers to measure hourly carapace temperature (Tc) of free-ranging terrapins in South Carolina from October 2007 to 2008 to examine the effects of month, sex, creek site, and tide on Tc and to determine the effects of month, sex, and time of day on terrapin basking frequency. Simultaneous measurements of environmental temperatures (Te; shallow mud, deep mud, water) allowed us to make inferences about terrapin microhabitat use. Terrapin Tc differed significantly among months and creek and between sexes. Terrapin microhabitat use also varied monthly, with shallow mud temperature being the best predictor of Tc November-March and water temperature being the best predictor of Tc April-October. Terrapins basked most frequently in spring and fall and males basked more frequently than females. Our study contributes to a fuller understanding of terrapin thermal biology and provides support for using dataloggers to investigate behavior and habitat use of aquatic ectotherms inhabiting dynamic environments., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Introduction: Children with dual sensory impairments are receiving cochlear implants; however, little is known regarding their language outcomes., Materials and Methods: Children between the ages of 6 months and 8 years with dual sensory impairment and cochlear implant(s) were recruited from across the United States to participate in an evaluation of language skills using the Reynell-Zinkin Developmental Scales, a tool validated on children with vision impairment and adapted for children with hearing loss. Basic demographic information was also collected from care givers., Results: Ninety-one children completed assessments after implantation. For receptive language abilities, 32% of children obtained a level of sound detection, 15% obtained the ability to understand simple words, 21% could identify words, 5% could follow simple directions, and 22% could follow directions related to the functional use of objects. Four children had no response to sound after cochlear implantation. For expressive language abilities, 49% only had sound production skills, 9% could jargon, 18% could communicate with some words, 12% could communicate with simple sentences, and 12% could communicate with complex sentences. Children with lower developmental ages (or quotients) tended to obtain lower level expressive language skills such as sound production and jargoning. Developmental abilities, rather than age at implant, were the most robust predictor associated with outcomes., Discussion: This information can guide cochlear implant centers when discussing outcomes with families in the cochlear implant candidacy process. There is great heterogeneity in outcomes and caution should be used in discussing possible language outcomes for children with dual sensory impairments.

Background: The efficacy of smoking cessation interventions for hospital patients has been well described, but we know little regarding implementation and outcomes of real-world programs., Objective: To describe the services provided and outcomes of an academic medical center-based tobacco treatment service (UKanQuit) located in the Midwestern United States., Method: This is a descriptive observational study. Both quantitative and qualitative data of all patients treated by UKanQuit over a 1-year period were analyzed., Results: Among 513 patients served, average interest in quitting was 7.9, standard deviation (SD) 2.9 on a scale of 0 to 10. More than 1 in 4 had been given an in-hospital medication to ameliorate withdrawal prior to seeing a counselor. Counselors recommended medication changes for 1 in 3 patients, helped 73% set a goal for quitting or reducing tobacco use, and fax referred 56% to quitlines. Six-month follow-up (response rate, 46%) found a 7-day abstinence rate of 32% among respondents for an intent-to-treat abstinence rate of 15%. Post-discharge, 74% made at least one serious quit attempt, 34% had used a quit smoking medication, but only 5% of those referred to the quitline reported using it., Conclusions: In a hospital setting, interest in quitting is high among smokers who requested to see a tobacco counselor but administration of inpatient medications remains low. Many smokers are making unassisted quit attempts post-discharge because utilization of cessation medications and quitline counseling were low. Fax-referral to quitline may not, on its own, fulfill guideline recommendations for post-discharge follow-up., (Copyright © 2010 Society of Hospital Medicine.)

To compare the fixation strengths of two arthroscopic anterior cruciate ligament reconstruction techniques, we harvested 10-mm bone-patellar tendon-bone grafts with 25-mm bone plugs from 12 fresh-frozen cadaveric knees. One knee of each pair was fixed using Acufex instruments and the two-incision technique; one knee was fixed using Arthrotek instruments and the one-incision technique. We used cannulated 9 x 25 mm Kurosaka screws for femoral and tibial tunnel fixation. All knees were mounted on the Instron Test System and were stressed to failure by recreating a pivot shift maneuver. The one-incision technique graft fixation was significantly stronger (mean failure, 695 N) than that with the two-incision technique (mean failure, 593 N). In all one-incision technique knees, either the patellar tendon graft avulsed off a bone plug or the plug broke. In five of six two-incision technique knees, the tibia bone plug pulled out around the interference screw. Patellar tendon graft length ranges from 90 to 105 mm, and the average two-incision technique tunnel length is 120 mm. The interference screw compressed the femoral bone plug into conical bone but compressed the tibial bone plug into cancellous bone in the two-incision technique, while in the one-incision technique the bone plug was compressed into cortical bone on both sides.

The care of patients with a skeletal deficiency currently involves the use of bone graft or a non-biologic material such as a metal or polymer. There are alternate possibilities in development which involve the growth of bone cells (osteoblasts) on degradable polymer scaffolds. These tissue engineering strategies require production of the polymeric scaffold, cellular harvest followed by either ex vivo or in vivo growth of the cells on the scaffold, and exploration of the interaction between the cell and scaffold. Research into these strategies utilizes cells from a variety of species, but clinical applications will likely require human osteoblasts. This study explores the process whereby human osteoblasts are harvested under sterile conditions during joint replacement surgery from normally discarded cancellous bone, transported from the operating room to the lab, and grown in culture. This process is feasible, and the cells express their phenotype via the production of alkaline phosphatase and collagen in culture.

Blood samples were collected from 26 moose (Alces alces ) and evaluated for the presence of an antigen that cross-reacted with antisera to bovine pregnancy-specific protein B (P-SPB). The objective of this study was to determine if the P-SPB radioimmunoassay (RIA) was a reliable indicator of pregnancy in these animals. In the first year of the study calf production the following summer was used as the index of previous pregnancy. In the second year all females were subjected to palpation per rectum after chemical immobilization. Seven of the 10 cows sampled in the first year were also sampled in the second year. All animals determined pregnant by rectal palpation were positive for P-SPB; however, P-SPB was not detected in males.

To determine whether the uterus was the source of serum pregnancy-specific protein B (PSPB) after calving, five beef cows were hysterectomized at 21 d postpartum and five served as intact controls. A single blood sample was taken from all cows immediately after calving and then twice weekly until 21 d postpartum. Beginning on d 22, blood samples were taken from all cows at 3-h intervals for 4 d and then twice weekly until 53 d postpartum. When the half-life calculated for the interval from d 1 to 21 was used as a covariate, the adjusted d-22 to -53 half-lives were 8.4 d for control cows vs 7.3 d for hysterectomized cows (P = .044). Data show that PSPB has a long half-life in the circulation and that the uterus is a minimal, if any, source of postpartum circulating PSPB. In another experiment, PSPB was measured weekly after calving in serum of 58 Polled Hereford and Simmental cows. Cows were exposed to fertile bulls and allowed to mate at every estrus. Observations were made for estrus, and progesterone concentrations in serum were measured to estimate the time of ovulations. Levels of PSPB were highest at approximately the time of calving, then decreased rapidly. Concentrations of PSPB were < 1 ng/mL by 80 d in eight cows that had not conceived since calving. Two cows eventually had nondetectable PSPB levels, one by 86 d and the other by 96 d after calving.(ABSTRACT TRUNCATED AT 250 WORDS)

A radioimmunoassay (RIA) for bovine pregnancy-specific protein B (bPSPB) has been shown to be a reliable test for pregnancy in cows. Pregnant ewes have a blood antigen that cross-reacts in this RIA. Two studies were conducted to determine the accuracy of detection of pregnancy in sheep using the bPSPB RIA. In Study 1, 33 ewe lambs were bred over a 70-d period in late fall. At 26, 56, and 83 d after the end of the breeding period, blood samples were collected for assay in the bPSPB RIA, and the Pregmatic 3 ultrasonic device was used to detect pregnancy. Pregmatic 3 detected pregnancy in 14, 27 and 28 ewes and nonpregnancy in 19, 6 and 3 ewes at Days 26, 56 and 83 past the breeding period, respectively. The bPSPB assay detected pregnancy in 32, 31 and 30 ewes and nonpregnancy in 1, 2 and 2 ewes at Days 26, 56 and 83 past breeding, respectively, Thirty ewes lambed and three did not. In Study 2, 180 multiparous ewes were bred over a 60-d period in summer. At 35 d after the end of the breeding period, blood samples were collected for assay in the RIA, and a real-time ultrasonic scan was done to detect pregnancy. Real-time ultrasonic testing detected pregnancy in 163 ewes and nonpregnancy in 17 ewes; whereas, the RIA detected pregnancy in 161 ewes and nonpregnancy in 19 ewes. One hundred fifty-nine ewes lambed and 21 did not. The bPSPB RIA detected pregnancy earlier and more accurately than the Pregmatic 3 ultrasonic device and was equally as accurate as the real-time scanning instrument. These studies demonstrate an accurate serological test for a pregnancy-specific antigen in sheep.

Two pregnancy-specific proteins were detected by immunoelectrophoresis using antisera developed to homogenates of bovine extraembryonic membranes. Antisera also reacted to extracts of endometrium from pregnant cows and extraembryonic fluids. However, antisera did not react with a preparation presumed to be bovine placental lactogen, fetuin, extracts of various somatic tissues from pregnant cows or extracts of endometrium from nonpregnant cows. One of the proteins had an estimated molecular weight of 65,000-70,000, an isoelectric point of 4.6-4.8 and yielded a reaction of identity with bovine alpha 1-fetoprotein by immunodiffusion. The second protein yielded a reaction of identity with bovine alpha 1-fetoprotein by immunodiffusion. The second protein had no immunological cross-reactivity with the known proteins or organ extracts which were tested. The molecular weight and isoelectric point was 47,000-53,000 and 4.0-4.4, respectively. These data demonstrate the presence of at least 2 pregnancy-specific proteins in cattle.

A study was conducted to evaluate the effect of a deficiency in dietary crude protein intake on postpartum reproductive performance of first-calf beef cows. Forty primigravid Hereford heifers were randomly assigned to two groups that were fed isocaloric (100% NRC requirements) diets containing .96 (adequate) or .32 (deficient) kg crude protein per head daily. Animals were individually fed from 150 d prepartum to 40 d postpartum and then were group-fed until the end of the experiment at 110 d postpartum. Total nutrient intake was increased by 33% at time of parturition to meet lactation requirements. Animals were artificially inseminated between 45 and 110 d postpartum when they showed estrus. Eighty-nine percent of those fed adequate protein showed estrus, whereas only 63% of protein-restricted heifers exhibited estrus (P less than .05). First-service conception (P less than .05; 71 vs 25%) and overall pregnancy rates (P less than .05; 74 vs 32%) were lower in protein-restricted heifers. Compared with those fed adequately, protein-restricted heifers had a tendency for longer intervals to first estrus (P less than .08; 75 vs 86 d), to first service (P less than .09; 76 vs 87 d) and to conception (P less than .09; 81 vs 92 d). Regardless of diet, weight at first estrus, weight at first service and average daily gain to 40 d postpartum were negatively correlated (P less than .01) with length of intervals from parturition to first estrus and first service.(ABSTRACT TRUNCATED AT 250 WORDS)

Jet ventilation via the Sanders injector during intravenous general anesthesia provides excellent operative conditions for CO2 laser microsurgery of the larynx. This technique, which includes complete muscle relaxation, is superior to traditional methods of anesthesia because the endotracheal tube is eliminated, thus improving the surgical field and reducing burn hazards owing to ignition of the tube. The laryngoscope has been modified to carry multiple ports into which a 14-gauge needle is inserted and the tip advanced just distal to the vocal cords. This needle is securely attached to the injector and pressure from the oxygen source is adjusted according to the patient's build and total compliance. Satisfactory arterial blood gases, superb operating conditions, safety, and rapid awakening make this the method of choice for most patients.

Tests for the detection of pregnancy early after insemination have not yet reached their full potential. Currently, the milk progesterone assay provides the earliest possible test, at an interval of one oestrous cycle after insemination, i.e. 17, 21 and 21 days in sheep, goats and cows respectively. This assay is pregnancy non-specific and rate of detection of pregnant animals is acceptable but less than desirable. Detection of activity of early pregnancy factor may develop into an excellent early test for many species, but the rosette inhibition test which is currently required has limited development and use. Pregnancy-specific protein B has been developed as a radioimmunoassay and is reliable under laboratory situations for ruminants. It can be used after 24 days of gestation in the cow. Application to field testing awaits development. Other pregnancy-associated or specific substances which are found in maternal body fluids might develop as pregnancy markers. Ultrasonic devices might provide very early detection in cattle but the expense of a test will limit application. All tests for pregnancy early after insemination have an inherent inaccuracy. Presence of an embryo at the time the test is applied will not assure pregnancy at the time of a confirmatory test, such as birth of live young or rectal examination in cows after 35 days of gestation. Therefore, no matter how early the test, a follow-up examination might be desirable in intensively managed herds or flocks. The animal industry is on the verge of new biotechnological approaches to reproductive management. The potential seems as great as the imagination.

The influence of dietary CP on circulating LH and anterior pituitary and hypothalamic function was examined. In Exp. 1, 28 cows were randomly assigned to four treatment groups: adequate CP (ADQ; .96 kg/d) or deficient CP (DEF; .32 kg/d) beginning at 90, 60 and 30 d before parturition and continued at a 33% increase in feed consumption after parturition. Cows were bled at 15-min intervals for 8 h on d 20, 40 and 60 after parturition. Pituitaries were collected on d 62 to analyze GnRH receptor numbers and gonadotropin content. Frequency of pulsatile LH release increased (P less than .05) from 20 to 60 d in ADQ cows. Basal and mean LH were not affected (P greater than .10) by CP restriction or by days after parturition. Crude protein did not affect pituitary GnRH receptors (P greater than .10), but it did affect pituitary LH content, FSH content and FSH concentration (P less than .05). In Exp. 2, 28 cows were assigned to treatment groups as in Exp. 1. All cows were challenged with GnRH (.22 micrograms/kg BW) at 20, 40 and 60 d after parturition and were bled every 30 min for 6 h. Responsiveness to GnRH increased with increased time after parturition (P less than .07). Deficient CP decreased GnRH-induced LH release (P less than .05). In Exp. 3, 12 cows were randomly assigned to ADQ or DEF CP beginning 120 d before parturition. All cows received 1 mg estradiol-17 beta (E2) on d 19, 39 and 59 after parturition and were bled every 30 min for 14 h beginning 14 h following E2. Response to E2 was unaffected by CP restriction (P greater than .10), whereas time to E2-induced LH peak decreased as time after parturition increased in ADQ cows (P less than .05). Results suggest that delayed return to estrus in CP-deficient postpartum beef cows might be due to reduced gonadotropin release from the anterior pituitary and decreased anterior pituitary responsiveness to GnRH.

Two language-delayed children received comprehension instruction on preposition-object phrases using a miniature linguistic system format to structure generalization. Results indicated generalization not only to untreated two-word combinations, but also to comprehension of four-word phrases. In addition, there was some generalization of production of two- and four-word structures.

The development of a double antibody radioimmunoassay for a bovine pregnancy-specific protein (pregnancy-specific protein B; PSPB) is presented. By means of this assay, PSPB could be measured in serum of pregnant cows. Five dairy cows were bled throughout gestation to measure serum levels of PSPB. Serum concentrations (means +/- SE) exceeded 1 ng/ml by 30 days postbreeding and increased gradually through three months (9 +/- 0.6 ng/ml), six months (35 +/- 6 ng/ml), and nine months (150 +/- 75 ng/ml) of gestation. Maximum levels of PSPB (542 +/- 144 ng/ml) were reached two days before parturition and then steadily declined to less than 78 ng/ml by 21 days postpartum. In 21 cows bled daily from 15 through 30 days postbreeding, PSPB could be measured in a few cows before and in most cows by 24 days after breeding. In a commercial herd of 102 beef cows, the assay could detect pregnancy earlier and more accurately than the routine method of rectal palpation. This radioimmunoassay measures a unique antigen that, for the first time, provides a serological method for detecting pregnancy in cows.