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Recently, LiGa 5 O 8 was claimed to be a p -type dopable ultrawide-bandgap oxide, based on measurements of undoped material. Here, the electronic properties of potential acceptor dopant impurities in LiGa 5 O 8 are calculated using hybrid density functional theory to evaluate their potential for causing p -type conductivity. As with the related compound LiGaO 2 , the heavy oxygen-derived valence bands lead to stable self-trapped holes in LiGa 5 O 8. Acceptor defects and dopants also bind trapped holes (or small polarons), which lead to large acceptor ionization energies. The calculations here indicate that neither native acceptor defects (such as cation vacancies or antisites) nor impurity dopants can give rise to p -type conductivity in LiGa 5 O 8. Optical transitions associated with these defects are also calculated, in order to allow for possible experimental verification of their behavior. [ABSTRACT FROM AUTHOR]

Moving beyond both a neoliberal as well as a 'heroic' conception of how the International Baccalaureate (IB) might 'make a better world', this paper focuses on the transformative potentiality of IBDP classroom pedagogy from the perspective of an experienced and critically minded educator, whose praxis has evolved across more than three decades of teaching IBDP courses in elite, well-established international schools around the world. In the IBDP teacher's account, particular attention is placed on the relational qualities of the (ideal) classroom culture and on the tensions between learner autonomy, teacher and learner authenticity and the critical imperative to interrogate privilege. We seek to provide a generative case for researchers and educators to reflect and find greater precision on the desired ends, possibilities and limits of critical and progressive pedagogies in school classrooms under contemporary conditions constituting our 'world in trouble'. More specifically for stakeholders of the IBDP, we offer up a promising orientation to IBDP classroom pedagogy in pursuit of the IB mission. [ABSTRACT FROM AUTHOR]

Background: The COVID-19 pandemic has placed an unprecedented strain on the US healthcare system, greatly impacting transplant centers. Objective: The purpose of this survey was to evaluate the impact of the COVID-19 pandemic on the transplant pharmacist workforce. Methods: A survey was disseminated electronically to assess the impact of the COVID-19 pandemic on the transplant pharmacist workforce. Respondents were asked to give background regarding transplant center, patient, population, and departmental staffing. Results: There were 67 total respondents from 56 transplant centers. In response to the COVID-19 pandemic, 55% of centers reported stopping non-life saving transplants, and a majority (89%) stopped living donor transplants altogether. The banning of caregivers on-site during education, reduction of bedside education teaching, and cancelling of group teaching classes occurred at 46%, 40%, and 22% of centers, respectively. Consequently, 42% of pharmacists surveyed felt that their confidence in patient and caregiver's understanding of medications had decreased since these changes have been implemented. Conclusions: Pharmacist perception of patient and caregiver understanding of transplant medications has decreased since before the COVID-19 pandemic. As health systems strategize resource allocation throughout the pandemic, the importance of patient education must be prioritized to sustain and improve transplant outcomes. [ABSTRACT FROM AUTHOR]

Although Ga 2 O 3 is widely believed to be one of the most promising ultrawide-bandgap semiconductors, its inability to be p -type doped hampers its future applications. Other oxides have recently emerged as potential competitors to Ga 2 O 3 , but their propensity for hole conductivity is less well known. Here, the stability of hole polarons is examined in pristine material and in the presence of impurities for a set of ultrawide-bandgap oxides ( Ga 2 O 3 , Al 2 O 3 , ZnGa 2 O 4 , MgGa 2 O 4 , LiGaO 2 , and GeO 2). Holes spontaneously self trap in all oxides investigated here. Acceptor impurities (such as group-I elements, N, and F) further stabilize these trapped holes, leading to large acceptor ionization energies. Hole trapping also leads to characteristic distortions and distinct optical transitions, which may explain some experimentally observed signals. These results indicate that achieving p -type conductivity in any of these oxides is unlikely, with the possible exception of GeO 2. [ABSTRACT FROM AUTHOR]

Attaining control over the electrical conductivity of gallium nitride through impurity doping is one of the foremost achievements in semiconductor science. Yet, unwanted contaminants and point defects continue to limit device performance, and experimental techniques alone are insufficient for elucidating the behavior of these unintentionally incorporated species. Methodological advancements have made first-principles calculations more powerful than ever and capable of quantitative predictions, though care must still be taken in comparing results from theory and experiment. In this Tutorial, we explain the basic concepts that define the behavior of dopants, unintentional impurities, and point defects in GaN. We also describe how to interpret experimental results in the context of theoretical calculations and also discuss how the properties of defects and impurities vary in III-nitride alloys. Finally, we examine how the physics of defects and impurities in GaN is relevant for understanding other wide-bandgap semiconductor materials, such as the II–IV-nitrides, boron nitride, and the transition metal nitrides. [ABSTRACT FROM AUTHOR]

We present an analysis of quantum confinement of carriers and excitons, and exciton fine structure, in metal halide perovskite (MHP) nanocrystals (NCs). Starting with coupled-band k · P theory, we derive a nonparabolic effective mass model for the exciton energies in MHP NCs valid for the full size range from the strong to the weak confinement limits. We illustrate the application of the model to CsPbBr3 NCs and compare the theory against published absorption data, finding excellent agreement. We then apply the theory of electron-hole exchange, including both short- and long-range exchange interactions, to develop a model for the exciton fine structure. We develop an analytical quasicubic model for the effect of tetragonal and orthorhombic lattice distortions on the exchange-related exciton fine structure in CsPbBr3, as well as some hybrid organic MHPs of recent interest, including formamidinium lead bromide (FAPbBr3) and methylammonium lead iodide (MAPbI3). Testing the predictions of the quasicubic model using hybrid density functional theory (DFT) calculations, we find qualitative agreement in tetragonal MHPs but significant disagreement in the orthorhombic modifications. Moreover, the quasicubic model fails to correctly describe the exciton oscillator strength and with it the long-range exchange corrections in these systems. Introducing the effect of NC shape anisotropy and possible Rashba terms into the model, we illustrate the calculation of the exciton fine structure in CsPbBr3 NCs based on the results of the DFT calculations and examine the effect of Rashba terms and shape anisotropy on the calculated fine structure. [ABSTRACT FROM AUTHOR]

Background: Efforts have been concentrated on improving vaccination administration during the pretransplant evaluation period. However, concern for human leukocyte antigen (HLA) sensitization subsequent to vaccination exists. Methods: A retrospective review of pediatric kidney transplant candidates (PKTCs) ≤18 years old who had received vaccinations between February 1, 2017 and November 30, 2019 was conducted. Emergence of de novo anti‐HLA antibody (HLA‐Ab) 3–4 weeks postvaccinations detected by the Luminex single antigen bead assay (SAB) was evaluated. Outcomes assessed included change in the HLA‐Ab mean fluorescence intensity (MFI) ≥25% from baseline, and change in preexisting HLA‐Ab MFI strength, categorized as weak: 1000–2999; moderate: 3000–9999; and strong: ≥10 000. Results: Sixty vaccinations were administered to 14 patients. Forty‐one potential de novo HLA‐Ab were detected in five patients. After additional antibody panel testing, 5/41 potential de novo HLA‐Ab were determined to be HLA specific; the remaining 36 were deemed nonspecific. The 5 de novo HLA‐Ab were observed in three patients and were deemed weak antibody (Ab). Median MFI showed a significant increase for nonspecific Ab, but not de novo HLA‐Ab. Median MFI values were deemed transient at 7–10 week follow‐up. No HLA‐donor–specific Ab developed posttransplant in the patients who developed de novo HLA‐Ab. Conclusion: Vaccination resulted in a transient increase in non‐HLA–specific Ab. The majority of responses were non‐HLA specific, hypothesized to be related to denatured antigens on single antigen beads. These data suggest limited clinical impact of vaccinations on the emergence of de novo HLA‐Ab. [ABSTRACT FROM AUTHOR]

• Ultra-wide bandgap semiconductors have immense potential as power switches. • The most serious materials challenge is control over electrical conductivity. • The most promising ultrawide-bandgap materials do not exhibit bipolar conductivity. Ultra-wide bandgap semiconductors, with bandgaps greater than 3.5 eV, have immense potential in power-switching electronic applications and ultraviolet light emitters. But the development of these materials faces a number of challenges, many of which relate to controlling electrical conductivity. In this work, we review the major obstacles for a set of these materials (focusing on AlGaN, AlN, BN, Ga 2 O 3 , Al 2 O 3 , and diamond) including limitations in n - and p -type doping and the effects of impurities and native point defects. We present an in-depth discussion on ultra-wide-bandgap nitride and oxide semiconductors, which face several similar challenges, as well as diamond, which presents a more unique scenario. The biggest obstacle for these semiconductors is attaining bipolar electrical conductivity, which means achieving both n -type and p -type conductivity within the same material. Toward this end, we also discuss potential future research directions that may lead to the development of bipolar ultra-wide bandgap semiconductor devices. [ABSTRACT FROM AUTHOR]

The 2018 eruption of Kīlauea Volcano produced large and destructive lava flows from the fissure 8 (Ahu 'aila 'au) vent with flow velocities up to 17 m s−1, highly variable effusion rates over both short (minutes) and long (hours) time scales, and a proximal channel or spillway that displayed flow features similar to open channel flow in river systems. Monitoring such dynamic vent and lava flow systems is a challenge. Our results demonstrate that infrasound, combined with ground-based observations and imagery from unoccupied aircraft systems (UAS), can be used to distinguish vent degassing activity from high-speed lava flow activity. We use spectral characteristics and the infrasound frequency index (FI) to distinguish spillway infrasound from vent infrasound. Comparing FI with flow speeds derived from UAS videos reveals that spillway infrasound only occurs when flow speeds were sufficiently high to cause a supercritical flow state and breaking waves (Froude values > 1.7), and we propose that the spillway signals are produced primarily through the interaction of the turbulent lava-free surface with the atmosphere. We show that FI can also provide a means to track bulk effusion rate. Our results indicate that infrasound offers a new way to characterize lava flow channel hydraulics and is a powerful tool for monitoring effusive eruptions when high-speed flows are possible. [ABSTRACT FROM AUTHOR]

Ga2O3 is a promising wide-bandgap material for electronic applications. The metastable orthorhombic κ phase is of particular interest due to its large predicted spontaneous electrical polarization. Here, we investigate how the properties of the orthorhombic phase can be tuned by alloying with In2O3. In particular, we determine how the lattice constants, bandgap, and band offsets change over the full range of possible alloy compositions. For completeness, we also compare to alloys with Al2O3. Lattice constants decrease linearly with Al content, while the bandgaps and conduction-band offsets increase non-linearly, with a bowing of 1.41 eV. Alloying with In2O3 allows to increase the lattice constants linearly and to decrease the bandgaps and conduction-band offsets non-linearly, with a bowing of 0.31 eV. Alloying, therefore, allows for the modification of the structural and electronic properties over a wide range, opening the possibility to tailor the alloy properties to specific applications. [ABSTRACT FROM AUTHOR]

Hole localization is a root cause of difficulties in p‐type doping of aluminum nitride. Herein, the stability of localized holes in AlN and their susceptibility to self‐trapping within bulk material or in the presence of isovalent elements and acceptor impurities are calculated. It is found that self‐trapped holes are metastable in bulk AlN, and also exhibit a very low barrier to detrapping. However, holes become trapped in the presence of acceptor impurities as well as isovalent elements such as B, In, and Sc, and may contribute to the broad luminescence observed in AlN alloys. It is also found that hole trapping contributes to the large ionization energies for acceptors in AlN. Most acceptors can also trap a second hole, becoming positively charged and further exacerbating difficulties in doping aluminum nitride p type. The stability of trapped holes is found to scale with atomic size mismatch to Al. [ABSTRACT FROM AUTHOR]

During infectious disease, pathogen load drives inflammation and immune response that together contribute to tissue injury often resulting in organ dysfunction. Pulmonary failure in SARS-CoV2-infected hospitalized COVID-19 patients is one such prominent example. Intervention strategies require characterization of the host-pathogen interaction by accurately assessing all of the above-mentioned disease parameters. To study infection in intact mammals, mice are often used as essential genetic models. Due to humane concerns, there is a constant unmet demand to develop studies that reduce the number of mice utilized while generating objective data. Here, we describe an integrated method of evaluating lung inflammation in mice infected with Pseudomonas aeruginosa or murine gammaherpesvirus (MHV)-68. This method conserves animal resources while permitting evaluation of disease mechanisms in both infection settings. Lungs from a single euthanized mouse were used for two purposes-biological assays to determine inflammation and infection load, as well as histology to evaluate tissue architecture. For this concurrent assessment of multiple parameters from a single euthanized mouse, we limit in-situ formalin fixation to the right lung of the cadaver. The unfixed left lung is collected immediately and divided into several segments for biological assays including determination of pathogen titer, assessment of infection-driven cytokine levels and appearance of cell death markers. In situ fixed right lung was then processed for histological determination of tissue injury and confirmation of infection-driven cell death patterns. This method reduces overall animal use and minimizes inter-animal variability that results from sacrificing different animals for different types of assays. The technique can be applied to any lung disease study in mice or other mammals. [ABSTRACT FROM AUTHOR]

Ga 2 O 3 has attracted significant attention as a wide-bandgap material for electronic applications. The orthorhombic κ phase is of interest due to its large predicted spontaneous electrical polarization. Here, we use density functional theory and hybrid functionals to investigate how alloying Ga 2 O 3 with Al 2 O 3 can be used to modify lattice constants, bandgaps, and conduction-band offsets. We find that increasing the Al content decreases lattice constants linearly, but that the increase in bandgaps and conduction-band offsets is non-linear, with a bowing of 1.41 eV. Structurally, there is a strong energetic preference of Al atoms to occupy octahedrally coordinated sites, and of Ga atoms to occupy tetrahedral sites. Ga will also occupy pentahedral sites, but at a small energy cost. The formation enthalpy of alloys is smaller than that of the pure materials, with ordered alloys with 50% Al having especially low formation enthalpies. These quantitative results can be used to guide experimental device design. [ABSTRACT FROM AUTHOR]

Bogoslof volcano, a back-arc volcano in Alaska's Aleutian arc, began an eruptive sequence in mid-December 2016 that ended in late August 2017, with 70 individual eruptive episodes. Because there were no local seismic or infrasound stations on the island, the Alaska Volcano Observatory (AVO) relied on distant geophysical networks and remote sensing techniques to assess activity during the eruption. AVO maintains six infrasound arrays to monitor activity along the Aleutian arc: Adak, the Island of Four Mountains, Okmok, Akutan, Sand Point, and Dillingham. Eruption detection at infrasound arrays is subject to local as well as mesoscale meteorological conditions that vary greatly over both short and long timescales. Infrasound detections from the array nearest to Bogoslof (Okmok), with a latency of about 3 min, played a crucial role in monitoring activity during the eruption. Despite the relative proximity of the Okmok array to Bogoslof (60 km), infrasound detections were not uniformly observed with only about two-thirds of the events successfully detected. The farthest array at Dillingham (816 km) detected approximately half of the explosive events, with all other arrays detecting less than half of the events. We compare observations with infrasound propagation model predictions, using both normal mode and parabolic equation forward models, to interpret the variation in detections of the 70 explosive events across the AVO infrasound network. The forward models utilize the newly created, publicly available AVO-G2S atmospheric reconstruction using numerical weather predictions data for the lower atmosphere, coupled with upper atmosphere empirical models of wind speeds and temperature. We find that long-range detections (> 100 km) of Bogoslof events are largely aligned with seasonal variability in favorable propagation conditions, while regional detections (< 100 km) are less consistent with propagation modeling. Understanding the output of numerical models in comparison to past observations will facilitate their use in future operational settings for AVO and other observatories. [ABSTRACT FROM AUTHOR]

The 2016–2017 shallow submarine eruption of Bogoslof volcano produced numerous infrasound signals over 9 months that were recorded on six Alaska Volcano Observatory (AVO) arrays at ranges of 59 to over 800 km from the volcano. The lack of geophysical monitoring near Bogoslof and the repeated production of volcanic clouds to flight levels made monitoring by remote infrasound critical during the eruption; for the first time, AVO relied extensively on automated infrasound detections from regional arrays to dispatch timely notifications of the ongoing activity. Most of the 70 eruptive events were detected on at least one array, but no array detected all of the events mainly because atmospheric conditions were highly variable during the eruption. Acoustic propagation modeling helps explain some of the variation in array detections but also highlights limitations in regional propagation models. To our knowledge, this is the first example of well-recorded infrasound from an explosive eruption occurring in shallow seawater, providing extensive insights into eruption dynamics in this unique environment. The dominance of low-frequency infrasound (0.1–1 Hz) is attributed to eruptions occurring beneath tens of meters of seawater. Higher-frequency infrasound signals were mostly limited to eruptions where the vent was isolated from major interaction with seawater or in several cases where a lava dome grew above sea level. [ABSTRACT FROM AUTHOR]

Characterizing the state of the volcanic vent is key for interpreting observational datasets and accurately assessing volcanic hazards. This is particularly true for remote, complex eruptions such as the 2016–2017 Bogoslof volcano, Alaska eruption sequence. Bogoslof's eruptions in this period were either shallow submarine or subaerial, or some combination of both. Our results demonstrate how low-frequency sound waves (infrasound), integrated with seismic and satellite data, can provide unique insight into shallow vent processes, otherwise not available. We use simple metrics, such as the infrasound frequency index (FI), event duration, and acoustic-seismic amplitude ratio, to look at changes in the elastic energy radiation and infer changes in seawater access to the vent. Satellite imagery before and after selected eruptions is used to ground-truth inferences on vent conditions. High FI and gradual increases in infrasound frequency content at Bogoslof correspond with transitions from submarine to subaerial vent conditions and a diminished or absent role of water, likely resulting in a drying out of the vent region. Event durations generally correlate with high FI and the range of FI values for each event, suggesting long duration events were more effective at drying out the vent region. A trend from low to high acoustic-seismic amplitude ratios for some long duration events also suggests an increase in acoustic efficiency as the vent dried out. We demonstrate that infrasound can serve as a robust indicator of seawater involvement for Bogoslof and other shallow submarine eruptions that may not be inferable from other datasets, particularly in near-real-time. [ABSTRACT FROM AUTHOR]

Hybridization among gar species (Pisces: Family Lepisosteidae) has only recently been documented, and relatively few occurrences have been reported. In the Fox River drainage of the Lake Michigan Basin in Wisconsin, apparent hybrids and introgressed individuals (hereafter "hybrids") of Longnose Gar (Lepisosteus osseus) and Shortnose Gar (L. platostomus) were widespread and numerous, constituting about 44% of the total gar population. Presumed hybrids could be readily distinguished by either their intermediate ratio of snout length to snout width or a low ratio, characteristic of Shortnose Gar, coupled with the presence of conspicuous spots on the top of the snout, an occasional Longnose Gar characteristic. Presumed hybrids had genetic matrilines (cytochrome b) of either Shortnose or Longnose Gar. Apparent hybrids occur commonly throughout the Fox River drainage, including the upper and lower Fox River, its major tributary the Wolf River, the riverine lakes Poygan, Winneconne, Butte des Morts, Winnebago, and Little Butte des Morts, and Green Bay, Lake Michigan, near the mouth of the lower Fox River. Evidence exists for possible hybrids in the adjacent Mississippi River basin and the Missouri River basin, but they appear to be less common and more localized. Extensive hybridization and introgression in the Fox River drainage may have been facilitated by the close phylogenetic relationship of Longnose and Shortnose Gar, the much greater abundance of Longnose relative to Shortnose Gar in the Fox River drainage, the apparent relatively recent colonization of the Fox River drainage by the Shortnose Gar, and the substantial modification and loss of gar spawning habitat in the Fox River drainage caused by dams and artificial water level regulation. [ABSTRACT FROM AUTHOR]

The current distribution and abundance of the 40 species of Goodeidae fishes known from Mexico are described, and a total of 84 Evolutionarily Significant Units (ESUs) is designated within these species. Two species and four ESUs are likely extinct with no captive populations, and three species and eight ESUs are probably extinct in the wild but have at least one captive population in Mexico, the United States, or Europe. Of the 35 extant species, the analyses indicate that nine should be considered as critically endangered, 14 as endangered, nine as vulnerable, and only three as least concern. Twenty-seven of these species have experienced substantial declines in distribution or abundance or both since 2000, and only eight appear to have remained relatively stable. Of the 72 extant ESUs, our analyses indicate that 29 should be considered as critically endangered, 21 as endangered, 18 as vulnerable, and only four as least concern. Brief summaries of the historic and current distributions and abundance of each species are provided, as well as ESU. Three strategies are recommended to conserve Mexican goodeids: protect the best-quality remaining habitats where goodeids still persist, restore degraded habitat and re-introduce species or ESUs where prac-tical, and establish captive populations to ensure continued survival of the many species and ESUs that will almost inevitably go extinct in the coming years. Limited resources require cooperation and collaboration between scientists, conservationists, and aquarium hobbyists for successful captive maintenance. [ABSTRACT FROM AUTHOR]

Climate warming is a threat to the survival of fishes adapted to cold water. Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta are two cold-water species occurring in streams in Wisconsin, where climate change may make these species particularly vulnerable. Vulnerable trout populations need to be identified to aid in the development of adaptation strategies. We used web-based stream temperature and fish-distribution models in FishVis to predict current (late twentieth century) and project future (mid-twenty-first century) distributions of Brook Trout and Brown Trout. The models predict the suitability of habitat for trout in individual reaches using environmental variables in a geographic information system, including adjacent and upstream channel characteristics, surficial geology, landcover, and climate. Future projections of air temperature and precipitation were obtained from 13 general circulation models downscaled for Wisconsin. Currently, 34,251 km of streams are suitable for Brook Trout and 20,011 km for Brown Trout. The models project a decline of 68% (10,995 km) in stream habitat for Brook Trout and a decline of 32% (13,668 km) for Brown Trout. These projected declines, while substantial, were lower than earlier estimates because our models account for projected increased precipitation that may enhance groundwater inputs and partially offset higher air temperatures. [ABSTRACT FROM AUTHOR]

Objective: The adult INTERMED is used to determine case complexity and psychosocial needs. We developed and validated a pediatric version of the INTERMED for children and adolescents with inflammatory bowel disease (IBD) and assessed its utility in predicting healthcare utilization.Methods: We performed a cross-sectional study of children (aged 8-17 y) with IBD (n = 148) and their parents, seen in a hospital-based clinic. Subjects completed semi-structured interviews that were scored on the 34 pIBD-INTERMED items. To assess inter-rater reliability, 40 interviews were videotaped and scored by a second assessor. Convergent and predictive validity were assessed by examining the relation of the pIBD-INTERMED to standardized measures of psychological, social, and family functioning, disease activity, and healthcare utilization.Results: Correlational analyses supported the validity of all five pIBD-INTERMED domains with very good inter-rater reliability (median r = 0.87) and internal consistency (α = 0.91) for the total complexity index. Ratings of 2-3 on the pIBD-INTERMED "mental health/cognitive threat" item were associated with greater odds of behavior and social problems (CBCL-Internalizing scale OR = 7.27, 95% CI 2.17-24.36); CBCL-Externalizing scale OR = 24.79, 95% CI 5.00-122.84), depression (Children's Depression Inventory OR = 8.52, 95% CI 1.70-43.02) and anxiety (Multidimensional Anxiety for Children OR = 11.57, 95% CI 3.00-45.37). The pIBD-INTERMED complexity index added significantly to the prediction of healthcare utilization, beyond the contribution of disease severity.Conclusions: The pIBD-INTERMED is a reliable and valid tool for identifying psychosocial risks and needs of children with IBD. It can be used to guide planning of individualized care and enhance interdisciplinary pediatric IBD care. [ABSTRACT FROM AUTHOR]

Kokanee salmon are a dwarf freshwater form of the anadromous sockeye salmon (Oncorhynchus nerka) native to the Pacific coast of North America and Asia and widely introduced in western North America as a sport and prey fish. Few kokanee salmon introductions have succeeded in eastern North America. A naturalized population of kokanee salmon has persisted for over 50 yr in Florence Lake, Wisconsin, an unlikely location given its relatively small size (21.4 ha), shallow maximum depth (7.6 m), low elevation (381 m), and southerly latitude (45.128N). Kokanee salmon completed their entire life cycle within the lake and rarely entered an accessible coldwater inlet stream. Spawning occurred during late October and early November along the lake shoreline. Spawning redds with defending males were observed in 1-2 m of water on sand/gravel/cobble substrate. Kokanee salmon growth in the lake was relatively rapid, and fish had a mean total length of 117 mm after their first growing season (age 0þ), 212 mm after their second (age 1þ), begin to mature and spawn after their third (age 2þ) at 317 mm for females and 324 mm for males, and were at 344 mm for females and 354 mm for males after their fourth (age 3þ). Few fish reproduced at age 4þ. Despite limited oxy-thermal habitat during summer, kokanee salmon appear to thrive in Florence Lake, perhaps because of cold inflows from the inlet and springs within the lake. [ABSTRACT FROM AUTHOR]

Fishes that depend on large‐river habitats have declined in many regions due to human alteration of both mainstems and tributaries. Conserving these species is often complicated by their dependence on long‐distance movements to complete their life cycle, but the location of key habitats is difficult to assess across multiple life history stages. Movement of large‐river fishes between mainstems and major tributaries is commonly observed, but the role of these exchanges at the population level is uncertain. We used shovelnose sturgeon (Scaphirhynchus platorynchus) as a case study for assessing the lifelong spatial ecology of large‐river fishes. Fin ray microchemistry data indicate that shovelnose sturgeon from the Mississippi and Wisconsin rivers represent a unified population that relies on connections among multiple large‐river habitats throughout life history. The tributary serves as an important spawning area, but fin ray chemistry data suggest larvae subsequently drift downstream to nursery habitats in the mainstem; an assertion that is supported by extensive field survey data. Our analyses underscore the lifelong importance of connections within river networks for maintaining viable populations of this, and likely other large‐river species that have been documented to use tributary habitats. These findings support a metapopulation perspective on species that depend on large‐river habitats, many of which are now highly altered and fragmented. For shovelnose sturgeon and species with similar life history, protecting or restoring linkages between mainstem rivers and their tributaries should be a conservation priority. [ABSTRACT FROM AUTHOR]

Cubic boron arsenide (c-BAs) exhibits an ultrahigh thermal conductivity (κ) approaching 1300 Wm−1 K−1 at room temperature. However, c-BAs is believed to incorporate high concentrations of crystal imperfections that can both quench κ and act as sources of unintentional p-type conductivity. Although this behavior has been attributed to native defects, we show here, using optical and magnetic resonance spectroscopies together with first-principles calculations, that unintentional acceptor impurities such as silicon and/or carbon are more likely candidates for causing the observed conductivity. These results also clarify that the true low-temperature bandgap of c-BAs is 0.3 eV higher than the widely reported value of ∼1.5 eV. Low-temperature photoluminescence measurements of c-BAs crystals reveal impurity-related recombination processes (including donor-acceptor pair recombination), and electron paramagnetic resonance experiments show evidence for effective mass-like shallow acceptors. Our hybrid density functional calculations indicate that native defects are incapable of giving rise to such signals. Instead, we find that group-IV impurities readily incorporate on the As site and act as shallow acceptors. Such impurities can dominate the electrical properties of c-BAs, and their influence on phonon scattering must be considered when optimizing thermal conductivity. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The investigation of the miscibility between active pharmaceutical ingredients (API’s) and polymeric excipients is of great interest for the formulation and development of amorphous solid dispersions, especially in the context of the prediction of the stability of these systems. Two different methods were applied to determine the miscibility between model compounds poly(vinylpyrrolidone-co-vinyl acetate) (PVPVA) and indomethacin (IND), viz. the measurement of the glass transition temperature ( T g ) and the melting point depression method framed on the Flory-Huggins theory. Measurement of the glass transition temperatures of the binary blends showed the formation of an amorphous single phase system between the PVPVA and the IND regardless of the composition. Variation of T g with the composition was well described by the Gordon-Taylor equation leading to the error of concluding lack of intermolecular interactions between the materials. Application of the Brostow-Chiu-Kalogeras-Vassilikou-Dova (BCKV) model shows a negative interaction parameter ( a 0 ) suggesting the presence of drug-drug intermolecular interactions. Application of the melting point depression method within the framework of the Flory-Huggins theory proved the miscibility of the system at temperatures close to the melting point of IND. [ABSTRACT FROM AUTHOR]

Halogens are emitted from volcanoes primarily as hydrogen halides (HCl, HF, HBr, and HI). Upon mixing with the atmosphere, chlorine and bromine species are partially converted to the halogen oxides OClO and BrO. Here we report on the spatial distribution of BrO and OClO in the gas plume emitted from Mount Pagan volcano, Northern Mariana Islands. We found enhanced BrO/SO2 ratios near the plume edges and a lack of OClO in the plume's core. Our results highlight the importance of in‐mixing of atmospheric oxidants for halogen oxide formation. They indicate that OClO can only be formed after most bromide dissolved in plume aerosols has been released to the gas phase. We conclude that Mount Pagan's gas emissions originated from a shallow magma body and were transported to the surface along dry degassing pathways and that the volcano's halogen emissions likely had significant impact on the oxidation capacity of the downwind atmosphere. Plain Language Summary: The halogens chlorine, fluorine, bromine, and iodine are commonly degassed from volcanoes and can cause ozone destruction in downwind areas. This occurs through a series of complex chemical reactions taking place within the first few minutes after emission that convert part of the emitted bromine and chlorine into bromine monoxide (BrO) and chlorine dioxide (OClO). These halogen oxides can be measured using remote sensing instruments commonly used to monitor volcanic degassing around the world. In this study, we examine the spatial distribution of BrO and OClO in the plume of Mount Pagan volcano. Our measurements allow insights into the chemical processes responsible for BrO and OClO formation. We find that in‐mixing of background air is of fundamental importance for the reaction scheme and that BrO is formed preferentially over OClO. This information will allow volcanologists to better link bromine emissions to associated volcanic activity and help in assessing the impact of volcanic halogen degassing on atmospheric chemistry. Key Points: The spatial distributions of bromine monoxide and chlorine dioxide were measured in the plume of Mount Pagan volcanoBoth species exhibited enhanced concentrations toward the edges of the plume. No chlorine dioxide was detected in the plume centerOur results suggest that chlorine dioxide is only formed once most bromide dissolved in plume aerosols has been released to the gas phase [ABSTRACT FROM AUTHOR]

The cisco ( Coregonus artedi) requires cold, well-oxygenated water and is threatened by climate warming and lake eutrophication, especially at the southern edge of its range in the Laurentian Great Lakes region. In this paper, a method is described to assess the quality, quantity, and variability of suitable cisco habitat. Two metrics are proposed to characterize existing cisco oxythermal habitat in this region: water temperature in the water column at a dissolved oxygen of 6 mg/L (TDO6) and 'cisco layer thickness' (CLT), the vertical extent of the water column within which water temperature is ≤22.8 °C and dissolved oxygen is ≥6 mg/L. It is proposed that values of TDO6 = 22.8 °C and CLT = 1 m be used as benchmarks to identify cisco lakes with potentially stressful oxythermal habitat. Long-term summer data from 14 Wisconsin cisco lakes with a wide range of limnological characteristics indicated that TDO6 varied from 4.2 to 27.5 °C and CLT from −6.2 to 66.7 m. Cisco abundance across lakes was greater at lower values of TDO6 and higher values of CLT, and non-attainments of the proposed benchmarks were most likely in lakes with remnant or extirpated cisco populations. Non-attainment of benchmarks could occur from late June through September, and three or more samples across the entire summer would be required to have a reasonable probability of detecting a non-attainment in TDO6 or CLT within any given year. Across years, to detect a single year of non-attainment with an 80% level of confidence, two years of sampling would be sufficient for CLT and three years for TD06; to detect more than one non-attaining year, three years of sampling for CLT and six years of sampling for TD06 would be required. Despite relatively high temporal variation in some lakes, the proposed metrics and benchmarks appear to have value for assessing cisco oxythermal habitat in the Great Lakes region. [ABSTRACT FROM AUTHOR]

Cell production and death are tightly regulated in the rapidly renewing gut epithelium, with proliferation confined to crypts and apoptosis occurring in villi and crypts. This study sought to determine how stress alters these compartmentalized processes. Wild-type mice made septic via cecal ligation and puncture had decreased crypt proliferation and increased crypt and villus apoptosis. Fabpi-TAg mice expressing large T-antigen solely in villi had ectopic enterocyte proliferation with increased villus apoptosis in unmanipulated animals. Septic fabpi-TAg mice had an unexpected increase in villus proliferation compared with unmanipulated littermates, whereas crypt proliferation was decreased. Cell cycle regulators cyclin D1 and cyclin D2 were decreased in jejunal tissue in septic transgenic mice. In contrast, villus and crypt apoptosis were increased in septic fabpi-TAg mice. To examine the relationship between apoptosis and proliferation in a compartment-specific manner, fabpi-TAg mice were crossed with fabpl-Bcl-2 mice, resulting in expression of both genes in the villus but Bcl-2 alone in the crypt. Septic bi-transgenic animals had decreased crypt apoptosis but had a paradoxical increase in villus apoptosis compared with septic fabpi-TAg mice, associated with decreased proliferation in both compartments. Thus, sepsis unmasks compartment-specific proliferative and apoptotic regulation that is not present under homeostatic conditions. [ABSTRACT FROM AUTHOR]

First-principles calculations of defects and electron–phonon interactions play a critical role in the design and optimization of materials for electronic and optoelectronic devices. The late Audrius Alkauskas made seminal contributions to developing rigorous first-principles methodologies for the computation of defects and electron–phonon interactions, especially in the context of understanding the fundamental mechanisms of carrier recombination in semiconductors. Alkauskas was also a pioneer in the field of quantum defects, helping to build a first-principles understanding of the prototype nitrogen-vacancy center in diamond, as well as identifying novel defects. Here, we describe the important contributions made by Alkauskas and his collaborators and outline fruitful research directions that Alkauskas would have been keen to pursue. Audrius Alkauskas' scientific achievements and insights highlighted in this article will inspire and guide future developments and advances in the field. [ABSTRACT FROM AUTHOR]

To identify past successes and future opportunities for improved fisheries management in Wisconsin, we synthesized size-structure information on 19 gamefish species from 1944 to 2012, incorporating data on more than 2 million measured individuals. Since the 1940s, mean and mean maximum sizes of five “gamefish” species (Lake SturgeonAcipenser fulvescens, Largemouth BassMicropterus salmoides, Smallmouth BassM. dolomieu, Northern PikeEsox lucius, and SaugerSander canadensis) have stayed fairly stable, and one (MuskellungeE.masquinongy) initially dropped and then rebounded—most likely as a product of increased catch-and-release fishing and restrictive harvest regulations. In contrast, four “panfish” species (i.e., BluegillLepomis macrochirus, GreenL. cyanellus, Yellow PerchPerca flavescens, and Black CrappiePomoxis nigromaculatus), which have not received the same conservation management attention, have experienced substantial and sustained erosions in size over the same period. Regulations for many species and species complexes have been cyclical over time, illustrating the challenge of consistently managing fisheries. Our long-term retrospective analysis was effective at identifying new opportunities for improved fisheries management in Wisconsin (i.e., panfish management). We therefore encourage other big data retrospective approaches within and across regions to identify past successes and future opportunities in other fisheries management programs. [ABSTRACT FROM PUBLISHER]

Background: Mortality is significantly higher in septic patients with cancer than in septic patients without a history of cancer. We have previously described a model of pancreatic cancer followed by sepsis from Pseudomonas aeruginosa pneumonia in which cancer septic mice have higher mortality than previously healthy septic mice, associated with increased gut epithelial apoptosis and decreased T cell apoptosis. The purpose of this study was to determine whether this represents a common host response by creating a new model in which both the type of cancer and the model of sepsis are altered. Methods: C57Bl/6 mice received an injection of 250,000 cells of the lung cancer line LLC-1 into their right thigh and were followed three weeks for development of palpable tumors. Mice with cancer and mice without cancer were then subjected to cecal ligation and puncture and sacrificed 24 hours after the onset of sepsis or followed 7 days for survival. Results: Cancer septic mice had a higher mortality than previously healthy septic mice (60% vs. 18%, p = 0.003). Cancer septic mice had decreased number and frequency of splenic CD4+ lymphocytes secondary to increased apoptosis without changes in splenic CD8+ numbers. Intestinal proliferation was also decreased in cancer septic mice. Cancer septic mice had a higher bacterial burden in the peritoneal cavity, but this was not associated with alterations in local cytokine, neutrophil or dendritic cell responses. Cancer septic mice had biochemical evidence of worsened renal function, but there was no histologic evidence of renal injury. Conclusions: Animals with cancer have a significantly higher mortality than previously healthy animals following sepsis. The potential mechanisms associated with this elevated mortality differ significantly based upon the model of cancer and sepsis utilized. While lymphocyte apoptosis and intestinal integrity are both altered by the combination of cancer and sepsis, the patterns of these alterations vary greatly depending on the models used. [ABSTRACT FROM AUTHOR]

In semiconductor-based photoelectrochemical (PEC) water splitting, carrier separation and delivery largely relies on the depletion region formed at the semiconductor/water interface. As a Schottky junction device, the trade-off between photon collection and minority carrier delivery remains a persistent obstacle for maximizing the performance of a water splitting photoelectrode. Here, it is demonstrated that the PEC water splitting efficiency for an n-SrTiO3 ( n-STO) photoanode is improved very significantly despite its weak indirect band gap optical absorption ( α < 104 cm−1), by widening the depletion region through engineering its doping density and profile. Graded doped n-SrTiO3 photoanodes are fabricated with their bulk heavily doped with oxygen vacancies but their surface lightly doped over a tunable depth of a few hundred nanometers, through a simple low temperature reoxidation technique. The graded doping profile widens the depletion region to over 500 nm, thus leading to very efficient charge carrier separation and high quantum efficiency (>70%) for the weak indirect transition. This simultaneous optimization of the light absorption, minority carrier (hole) delivery, and majority carrier (electron) transport by means of a graded doping architecture may be useful for other indirect band gap photocatalysts that suffer from a similar problem of weak optical absorption. [ABSTRACT FROM AUTHOR]

In semiconductor-based photoelectrochemical (PEC) water splitting, carrier separation and delivery largely relies on the depletion region formed at the semiconductor/water interface. As a Schottky junction device, the trade-off between photon collection and minority carrier delivery remains a persistent obstacle for maximizing the performance of a water splitting photoelectrode. Here, it is demonstrated that the PEC water splitting efficiency for an n -SrTiO3 (n -STO) photoanode is improved very significantly despite its weak indirect band gap optical absorption (α < 104 cm-1), by widening the depletion region through engineering its doping density and profile. Graded doped n -SrTiO3 photoanodes are fabricated with their bulk heavily doped with oxygen vacancies but their surface lightly doped over a tunable depth of a few hundred nanometers, through a simple low temperature reoxidation technique. The graded doping profile widens the depletion region to over 500 nm, thus leading to very efficient charge carrier separation and high quantum efficiency (>70%) for the weak indirect transition. This simultaneous optimization of the light absorption, minority carrier (hole) delivery, and majority carrier (electron) transport by means of a graded doping architecture may be useful for other indirect band gap photocatalysts that suffer from a similar problem of weak optical absorption. [ABSTRACT FROM AUTHOR]

While the child serving system has been measuring and monitoring outcomes for more than three decades, the promise of actually using outcomes to support changes in the functioning of the system has not yet lived up to its full potential. In this Editorial, I review what I believe to be a number of ways that we have mistakenly conceptualized outcomes. By working through these myths, we can begin to teach the system to learn from its own experiences to better help child and families. [ABSTRACT FROM AUTHOR]

Acceptor defects and impurities play a critical role in the performance of GaN-based devices. Mg is the only acceptor impurity that gives rise to p-type conductivity, while other acceptors (such as C [ABSTRACT FROM AUTHOR]

In order to understand the differential presentation of trauma stress symptoms over the course of development from children to adolescents, a sample of more than 11,000 children and adolescents were studied who were identified as to whether they had experienced multiple trauma experiences prior to placement in child welfare custody. Six age groups were compared on their presentation of symptoms associated with traumatic experiences. Trauma stress symptoms were dramatically different for children and adolescents despite the similarity of trauma experiences. Implications for understanding and addressing multiple trauma experiences across a developmental trajectory are discussed. [ABSTRACT FROM AUTHOR]

Size-exclusion chromatography (SEC),coupled with differentialviscometry detection (SEC/DV), is applied to the dilute suspensioncharacterization of solvent-swollen cross-linked polymeric nanoparticles(PNPs). Cross-linked, unimolecular polymeric nanoparticles in the5–50 nm weight-average diameter (dw) range were prepared by batch and semibatch microemulsion polymerizationtechniques and isolated. SEC and SEC/DV characterization techniquesyield, based on the principle of universal calibration, a wealth ofinformation regarding the structural attributes of PNPs, includingapparent and absolute molecular weight distributions, apparent andabsolute molecular weight averages, peak and weight-average particlediameters, particle size distributions in both the solvent-swollenand solvent-free states, particle conformation (shape), and an estimateof the volumetric swell factor. These structural parameters are criticalto understanding PNP performance, and all are obtained in a singlerapid chromatographic experiment, when conducted under conditionswhere universal calibration applies. Particle sizes determined undersuch conditions are in excellent agreement with those obtained bydynamic light scattering, transmission electron microscopy, hydrodynamicchromatography, and SEC/static light scattering (SEC/SLS). In addition,Mark–Houwink exponents of approximately zero were found acrossthe molecular weight and size distribution of many of these tightlycross-linked PNPs, which is consistent with a spherical particle conformationin these dilute suspensions. The SEC/DV methods are especially valuableto characterize the diameter, volume swell factor, and suspensionconformation of small (4–5 nm dw) PNPs. [ABSTRACT FROM AUTHOR]

The article considers an example where tragic spectacle is likely to lead spectators neither to a sense of reconciliation nor to a recognition of transcendent. Topics discussed include philosopher Plato's position that tragedy arouses emotions that should be kept in check, the huge discrepancy between high abstraction of claims for reading tragedy and actual content of the plays labeled as tragedies and Alexandre Hardy's "Scedase" as an example of tragic representation of horrible actions.

Abstract: Determining the optimal well location in a reservoir is a challenging problem. It involves taking several factors into account, including geological uncertainty, reservoir and fluid properties, economic costs, and technical ability. Most research on well placement optimization under uncertainty has assumed static uncertainty in the reservoir parameters, until the introduction of the pseudohistory concept. The pseudohistory concept incorporates the field's probable history and results in the determination of optimal locations of future wells with greater certainty. This approach, however, requires an excessive number of simulations and may not be practical for optimization of a reservoir model having a large number of geological realizations. In this study, we use an ensemble Kalman filter (EnKF) to perform history matching of the PUNQ-S3 reservoir model using data from six production wells over an eight-year period. This is followed by well placement optimization using a genetic algorithm (GA) combined with pseudohistory matching, carried out over two years, following the placement of the first future well. Thus, this approach not only provides increased certainty in optimal well placement but also, using EnKF as a history matching method, requires only a single “best estimate” realization for objective function evaluation during GA optimization. As a result, the total time taken to find the optimal well locations is significantly reduced. We illustrate this through comparison with the previous research. [Copyright &y& Elsevier]

We investigate the electronic structure of carbon and nitrogen impurities, which are commonly incorporated during atomic-layer deposition of high-κ oxides such as Al2O3 and HfO2. The impact on metal-oxide-semiconductor devices is assessed by examining formation energies, transition levels, and band alignment between the oxide and semiconductors such as GaN, Si, and III-As. Carbon introduces charge-state transition levels near the semiconductor conduction-band edges, resulting in border traps and/or leakage current. Nitrogen acts as a source of negative fixed charge but may also be effective in alleviating the problem of carrier traps associated with native defects. [ABSTRACT FROM AUTHOR]

We perform first-principles calculations to investigate the electronic structure of native defects in various oxide dielectrics to address the impact of defects on GaN/oxide metal-oxide-semiconductor (MOS) devices. We calculate defect formation energies in Al2O3, HfO2, and LaAlO3, as a function of the chemical potentials and of the Fermi-level position in the band gap. By aligning the conduction-band and valence-band edges of these oxides to those of GaN, the role of native defect as charge-trap or fixed-charge centers in GaN-based MOS devices is examined. We find that oxygen vacancies in the oxide dielectrics result in charge-state transition levels near the GaN conduction-band edge. They can therefore introduce border traps and/or leakage current through the gate dielectric in the n-GaN/oxide MOS devices such as MOS field-effect-transistors. While the transition levels for other defects are well away from the GaN conduction-band edge, these defects are stable in non-neutral charge states and thus act as sources of fixed charge in MOS devices. [ABSTRACT FROM AUTHOR]

Complications after tracheal repair in the past have included wound infections, tracheal stenosis, "spitting" of sutures, and tracheoesophageal fistulas. Modern operative approaches have significantly decreased the incidence of these complications. We conducted retrospective data collection using the TRACS database. Changes that preceded the time interval of the study included the following: 1) an emphasis on clinical (rather than endoscopic) recognition of injury; 2) minimal peritracheal dissection and repair with absorbable sutures; 3) limited use of "protective" tracheostomies; and 4) use of muscle buttresses to cover tracheal repairs, especially in patients with combined injuries. From 1997 to 2010, 22 patients were treated for wounds to the trachea (cervical 20, thoracic 2). The mechanism of injury was a gunshot wound in 15 patients and a stab wound in seven. A clinical diagnosis of the need for cervical operation or of a tracheal injury was made in 19 patients (86%), whereas three patients had positive diagnostic studies. Direct tracheal repair (No. 19) or evaluation of a superficial injury (No. 1) was performed in 20 patients, and three (15%) had a tracheostomy performed. Combined injuries were present in 12 patients (55%), most commonly to the esophagus (10 of 12 [83%]), and 10 of these 12 patients had vascularized buttresses applied to the tracheal repair. There were seven significant complications in patients with combined injuries to the esophagus or carotid artery. One patient (4.5%) died. Patients with penetrating tracheal injuries most commonly present with overt findings. Modern techniques of repair have eliminated many of the complications noted in the past. [ABSTRACT FROM AUTHOR]

We present a theoretical study of the broadening of defect luminescence bands due to vibronic coupling. Numerical proof is provided for the commonly used assumption that a multidimensional vibrational problem can be mapped onto an effective one-dimensional configuration coordinate diagram. Our approach is implemented based on density functional theory with a hybrid functional, resulting in luminescence line shapes for important defects in GaN and ZnO that show unprecedented agreement with experiment. We find clear trends concerning effective parameters that characterize luminescence bands of donor- and acceptor-type defects, thus facilitating their identification. [ABSTRACT FROM AUTHOR]

Perennial coolwater streams (maximum daily mean water temperature 20.7–24.6°C; 90th percentile annual exceedence flow≥0.0283m3/s) are common in the Laurentian Great Lakes region of North America, including the state of Wisconsin, but they lack specific and effective bioassessment tools. I used landscape-scale ecological modeling of geographically referenced data on stream location, stream and valley slope, watershed surficial geology, air temperatures, riparian and watershed land cover, watershed road and population densities, and watershed nutrient and wastewater inputs to classify Wisconsin stream sites based on water temperature, flow, and degree of environmental degradation. Fish data from sites classified as perennial coolwater were then analyzed with objective standardized procedures to develop coolwater indices of biotic integrity (IBI). Because of substantial differences in their fish assemblages, separate IBI's were formulated for cool-cold transition (20.7–22.5°C) and cool–warm transition (22.6–24.6°C) streams. The cool–cold transition IBI had five metrics: numbers of darter, madtom, and sculpin species, of coolwater species, and of intolerant species, and the percentages of individuals as tolerant species and as generalist feeders. Scoring criteria differed between northern and southern Wisconsin (boundary at 44.6°N latitude) for the coolwater species metric. The cool–warm transition IBI also had five metrics: numbers of native minnow, of intolerant, and of benthic invertivore species, and percentages of individuals as tolerant species and as omnivores. Scoring criteria differed between small and large streams (boundary at 200km2 watershed area) for the intolerant species, benthic invertivore species, and percentage tolerants metrics. In validation tests, scores for both IBI's were significantly related to independent measures of human disturbance, indicating that the IBI's would be useful tools for assessing the environmental quality of coolwater streams. However, for any given level of human disturbance, scores for both IBI's varied substantially, suggesting that multiple IBI samples from multiple sites would be needed to provide a reliable evaluation of a particular stream segment. [ABSTRACT FROM AUTHOR]

Several epidemiological studies have reported that large numbers of children and adolescents suffer from diagnosable psychiatric conditions, however most of them do not receive treatment. The schools are a key setting where youth with mental health problems are identified and linked to treatment. In this study we examine the demographic and clinical characteristics of youth referred to a school-based mental health intervention, the youth characteristics associated with continued participation in the intervention at 6-month follow up, and the youth characteristics that are associated with intensity of service use at 6-month follow up. The data were analyzed using descriptive frequencies, Chi-square tests and t tests, and bivariate and multivariable Poisson regressions. Demographic and clinical characteristics were not found to be significantly associated with discontinuing services before 6-months; however, several youth who discontinued services before 6-months had clinical characteristics suggesting a possible need for services. Youth demographic (sex, race) and clinical (diagnosis, suicidal ideation, alcohol/drug use, psychiatric medication use, and physical health) characteristics were significantly associated with intensity of service use in the multivariable analysis. This study underscores the importance of monitoring program participation, after the referral has been made and services have been accessed, to assure that youth participate in treatment long enough to obtain clinical benefits. [ABSTRACT FROM AUTHOR]

Background: The optimal surgical management of patients found to have unresectable pancreatic cancer at open exploration remains unknown. Methods: Records of patients who underwent non-therapeutic laparotomy for pancreatic cancer during 2000-2009 and were followed until death at Memorial Sloan-Kettering Cancer Center, New York, were reviewed. Results: Over the 10-year study period, 157 patients underwent non-therapeutic laparotomy. Laparotomy alone was performed in 21% of patients; duodenal bypass, biliary bypass and double bypass were performed in 11%, 30% and 38% of patients, respectively. Complications occurred in 44 (28%) patients. Three (2%) patients died perioperatively. Postoperative interventions were required in 72 (46%) patients following exploration. The median number of inpatient days prior to death was 16 (interquartile range: 8-32 days). Proportions of patients requiring interventions were similar regardless of the procedure performed at the initial operation, as were the total number of inpatient days prior to death. Patients undergoing gastrojejunostomy required fewer postoperative duodenal stents and those undergoing operative biliary drainage required fewer postoperative biliary stents. Conclusions: In this study, duodenal, biliary and double bypasses in unresectable patients were not associated with fewer invasive procedures following non-therapeutic laparotomy and did not appear to reduce the total number of inpatient hospital days prior to death. Continued effort to identify unresectability prior to operation is justified. [ABSTRACT FROM AUTHOR]

Background: Only one tumor site is usually biopsied to determine the histologic features of that patient’s entire tumor burden. We hypothesized that there are significant histologic and functional differences in primary neuroendocrine tumors (NETS) and their nodal or organ metastases. We also hypothesized that limited tumor sampling could lead to erroneous assumptions about the tumor’s histologic characteristics and clinical behavior. Materials and Methods: Thirteen patients with metastatic well differentiated midgut NETS underwent simultaneous removal of their primary tumor, nodal metastasis, and organ metastasis. Each tumor site was stained quantitatively for Ki-67, chromogranin A (CGA), synaptophysin, CD31, and Factor VIII. Samples were also evaluated with in vitro tumor angiogenesis and drug chemoresistance assays. Results: Ki-67 staining was nearly identical at all sites tested. Quantitative stains for CGA, synaptophysin, cluster of differentiation 31 (CD31), and Factor VIII varied considerably among the patient’s three tissue site samples. Only 6% of the tissue samples tested against a battery of chemotherapeutic agents exhibited susceptibility to a single drug at all three tumor sites. In contrast, several antiangiogenic agents exhibited uniform effectiveness across all three tissue sites in multiple patients. Conclusions: Sampling only one NET tumor site may lead to erroneous assumptions about the tumor’s histologic features and functional behavior. Evaluation of primary tumors and their nodal and organ metastasis may be necessary to optimize clinical decision making. [Copyright &y& Elsevier]