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Proton beams driven by chirped pulse amplified lasers have multi-picosecond duration and can isochorically and volumetrically heat material samples, potentially providing an approach for creating samples of warm dense matter with conditions not present on Earth. Envisioned on a larger scale, they could heat fusion fuel to achieve ignition. We have shown in an experiment that a kilojoule-class, multi-picosecond short pulse laser is particularly effective for heating materials. The proton beam can be focussed via target design to achieve exceptionally high flux, important for the applications mentioned. The laser irradiated spherically curved diamond-like-carbon targets with intensity 4 × 1018 W/cm2, producing proton beams with 3 MeV slope temperature. A Cu witness foil was positioned behind the curved target, and the gap between was either empty or spanned with a structure. With a structured target, the total emission of Cu Kα fluorescence was increased 18 fold and the emission profile was consistent with a tightly focussed beam. Transverse proton radiography probed the target with ps order temporal and 10 μm spatial resolution, revealing the fast-acting focussing electric field. Complementary particle-in-cell simulations show how the structures funnel protons to the tight focus. The beam of protons and neutralizing electrons induce the bright Kα emission observed and heat the Cu to 100 eV.

Intense lasers can accelerate protons in sufficient numbers and energy that the resulting beam can heat materials to exotic warm (10 s of eV temperature) states. Here we show with experimental data that a laser-driven proton beam focused onto a target heated it in a localized spot with size strongly dependent upon material and as small as 35 μm radius. Simulations indicate that cold stopping power values cannot model the intense proton beam transport in solid targets well enough to match the large differences observed. In the experiment a 74 J, 670 fs laser drove a focusing proton beam that transported through different thicknesses of solid Mylar, Al, Cu or Au, eventually heating a rear, thin, Au witness layer. The XUV emission seen from the rear of the Au indicated a clear dependence of proton beam transport upon atomic number, Z, of the transport layer: a larger and brighter emission spot was measured after proton transport through the lower Z foils even with equal mass density for supposed equivalent proton stopping range. Beam transport dynamics pertaining to the observed heated spot were investigated numerically with a particle-in-cell (PIC) code. In simulations protons moving through an Al transport layer result in higher Au temperature responsible for higher Au radiant emittance compared to a Cu transport case. The inferred finding that proton stopping varies with temperature in different materials, considerably changing the beam heating profile, can guide applications seeking to controllably heat targets with intense proton beams.

Following a disturbance, dispersal shapes community composition as well as ecosystem structure and function. For fungi, dispersal is often wind or mammal facilitated, but it is unclear whether these pathways are complementary or redundant in the taxa they disperse and the ecosystem functions they provide. Here, we compare the diversity and morphology of fungi dispersed by wind and three rodent species in recently harvested forests using a combination of microscopy and Illumina sequencing. We demonstrate that fungal communities dispersed by wind and small mammals differ in richness and composition. Most wind-dispersed fungi are wood saprotrophs, litter saprotrophs, and plant pathogens, whereas fungi dispersed in mammal scat are primarily mycorrhizal, soil saprotrophs, and unspecified saprotrophs. We note substantial dispersal of truffles and agaricoid mushrooms by small mammals, and dispersal of agaricoid mushrooms, crusts, and polypores by wind. In addition, we find mammal-dispersed spores are larger than wind-dispersed spores. Our findings suggest that wind- and small-mammal-facilitated dispersal are complementary processes and highlight the role of small mammals in dispersing mycorrhizal fungi, particularly following disturbances such as timber harvest., (© 2023 The Ecological Society of America.)

Enhanced surface mobility is critical in producing stable glasses during physical vapor deposition. In amorphous selenium (a-Se) both the structure and dynamics of the surface can be altered when exposed to above-bandgap light. Here we investigate the effect of light on the properties of vapor-deposited a-Se glasses at a range of substrate temperatures and deposition rates. We demonstrate that deposition both under white light illumination and in the dark results in thermally and kinetically stable glasses. Compared to glasses deposited in the dark, stable a-Se glasses formed under white light have reduced thermal stability, as measured by lower density change, but show significantly improved kinetic stability, measured as higher onset temperature for transformation. While light induces enhanced mobility that penetrates deep into the surface, resulting in lower density during vapor deposition, it also acts to form more networked structures at the surface, which results in a state that is kinetically more stable with larger optical birefringence. We demonstrate that the structure formed during deposition with light is a state that is not accessible through liquid quenching, aging, or vapor deposition in the dark, indicating the formation of a unique amorphous solid state., Competing Interests: The authors declare no competing interest.

Animals are often the primary dispersers of seeds and fungal spores. Specialist species that consume fruits or fungal fruiting bodies (sporocarps) as their main food source are thought to play a more important role in dispersal networks compared to generalist species. However, dispersal networks are often based on occurrence data, overlooking the influence of animal abundance and dispersal effectiveness on network interactions. Using rodent-mycorrhizal fungi networks, we determined how diet specialization and abundance influence the role of rodent species in dispersing fungal spores in temperate forests of northern New Hampshire, USA. We tracked the interactions of five rodent species and 34 fungal taxa over a 3-yr period across hardwood, mixed, and softwood forest stands. We accounted for fluctuations in rodent abundance and differences in the number of spores dispersed in rodent scat. Myodes gapperi, a fungal specialist, dispersed a more diverse spore community than rodent generalists and was consistently the most important disperser in forest types with high fungal availability. Nevertheless, during years when generalist species such as Tamias striatus and Peromyscus maniculatus reached high abundance, their relative importance (species strength) in networks approached or even surpassed that of M. gapperi, particularly in forest types where M. gapperi was less common and fungal availability was low. Increased numbers of generalists enhanced network interaction diversity and the number of fungal taxa dispersed, the timing of which was coincident with seedling establishment following masting, a stage when inoculation by mycorrhizal fungi is critical for growth and survival. Our findings suggest that although specialists play key roles in dispersing mycorrhizal fungal spores, generalists play a heretofore underappreciated role., (© 2020 by the Ecological Society of America.)

Many plant and fungal species use volatile organic compounds (VOCs) as chemical signals to convey information about the location or quality of their fruits or fruiting bodies to animal dispersers. Identifying the environmental factors and biotic interactions that shape fruit selection by animals is key to understanding the evolutionary processes that underpin chemical signaling. Using four Elaphomyces truffle species, we explored the role of fruiting depth, VOC emissions, and protein content in selection by five rodent species. We used stable isotope analysis of nitrogen (δ 15 N) in truffles to estimate fruiting depth, proton-transfer-reaction mass spectrometry to determine volatile emission composition, and nitrogen concentrations to calculate digestible protein of truffles. We coupled field surveys of truffle availability with truffle spore loads in rodent scat to determine selection by rodents. Despite presumably easier access to the shallow fruiting species, E. americanus (0.5-cm depth) and E. verruculosus (2.5-cm depth), most rodents selected for truffles fruiting deeper in the soil, E. macrosporus (4.1-cm depth) and E. bartlettii (5.0-cm depth). The deeper fruiting species had distinct VOC profiles and produced significantly higher quantities of odiferous compounds. Myodes gapperi (southern red-backed vole), a fungal specialist, also selected for truffles with high levels of digestible protein, E. verruculosus and E. macrosporus. Our results highlight the importance of chemical signals in truffle selection by rodents and suggest that VOCs are under strong selective pressures relative to protein rewards. Strong chemical signals likely allow detection of truffles deep within the soil and reduce foraging effort by rodents. For rodents that depend on fungi as a major food source, protein content may also be important in selecting truffles., (© 2019 by the Ecological Society of America.)

Identifying the mechanisms that structure niche breadth and overlap between species is important for determining how species interact and assessing their functional role in an ecosystem. Without manipulative experiments, assessing the role of foraging ecology and interspecific competition in structuring diet is challenging. Systems with regular pulses of resources act as a natural experiment to investigate the factors that influence the dietary niches of consumers. We used natural pulses of mast-fruiting of American beech ( Fagus grandifolia ) to test whether optimal foraging or competition structure the dietary niche breadth and overlap between two congener rodent species ( Peromyscus leucopus and P. maniculatus ), both of which are generalist consumers. We reconstructed diets seasonally over a 2-year period using stable isotope analysis (δ 13 C, δ 15 N) of hair and of potential dietary items and measured niche dynamics using standard ellipse area calculated within a Bayesian framework. Changes in niche breadth were generally consistent with predictions of optimal foraging theory, with both species consuming more beechnuts (a high-quality food resource) and having a narrower niche breadth during masting seasons compared to nonmasting seasons when dietary niches expanded and more fungi (a low-quality food source) were consumed. In contrast, changes in dietary niche overlap were consistent with competition theory, with higher diet overlap during masting seasons than during nonmasting seasons. Overall, dietary niche dynamics were closely tied to beech masting, underscoring that food availability influences competition. Diet plasticity and niche partitioning between the two Peromyscus species may reflect differences in foraging strategies, thereby reducing competition when food availability is low. Such dietary shifts may have important implications for changes in ecosystem function, including the dispersal of fungal spores., Competing Interests: The authors declare no competing interests., (© 2019 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Colorectal cancer accounts for 11% of all cancer-related deaths in Ireland. With the aim of diagnosing these cancers at an earlier stage, and detecting premalignant lesions, the National Screening Service (NSS) offered a fecal immunochemical test (FIT) to all individuals aged 60 to 69. All individuals in the age range were contacted by post and invited to participate in the programme. Those with a positive FIT result were offered a colonoscopy in an internationally accredited unit. From an eligible population of 488,628, 196,238 individuals participated giving an uptake of 40.2%. Commencing at a FIT threshold of 20 μg Hg/g feces, the positivity rate was 8.6%, which overwhelmed colonoscopy capacity and, thus, the threshold was increased to 45 μg, resulting in an overall 5% positivity rate. A total of 520 individuals had cancer detected (68.3% stage I or II), of which 104 were removed endoscopically (pT1s). Adenomas were present in 54.2% of all colonoscopies, 17.4% deemed high risk. Despite a lower uptake, males were twice as likely to have colorectal cancers as females and had a 59% increased rate of high-risk adenomas diagnosed. Challenges facing the programme include increasing participation, especially among males, and increasing colonoscopy capacity. The ability to alter the sensitivity of FIT to match colonoscopy capacity is a valuable option for such a programme as it ensures that the maximum public health benefit can be achieved within available resources., (©2018 American Association for Cancer Research.)

We describe five new species of Elaphomyces from Bartlett Experimental Forest, New Hampshire, USA ( E. americanus , E. bartlettii , E. macrosporus , E. oreoides , and E. remickii ) and revise the description of a sixth previously published species ( E. verruculosus ). Of the five new species, E. bartlettii and E. remickii are only known from New Hampshire whereas E. americanus, E. macrosporus, and E. oreoides are widely distributed in eastern North America. Elaphomyces verruculosus is the most widespread and abundant Elaphomyces species in eastern North America with a distribution extending from eastern Canada south to northeastern Mexico. All six Elaphomyces species are putatively associated with Tsuga canadensis , a tree species in regional decline. For five of the six Elaphomyces species, we report partially consumed ascomata or rodent fecal samples containing spores, indicating that small mammals play a key role in dispersing these Elaphomyces species and that the Elaphomyces are an important part of the small mammals' diet.

The advent of high-intensity lasers enables us to recreate and study the behaviour of matter under the extreme densities and pressures that exist in many astrophysical objects. It may also enable us to develop a power source based on laser-driven nuclear fusion. Achieving such conditions usually requires a target that is highly uniform and spherically symmetric. Here we show that it is possible to generate high densities in a so-called fast-ignition target that consists of a thin shell whose spherical symmetry is interrupted by the inclusion of a metal cone. Using picosecond-time-resolved X-ray radiography, we show that we can achieve areal densities in excess of 300 mg cm(-2) with a nanosecond-duration compression pulse--the highest areal density ever reported for a cone-in-shell target. Such densities are high enough to stop MeV electrons, which is necessary for igniting the fuel with a subsequent picosecond pulse focused into the resulting plasma.

Purpose: Survivin has been shown to be an important mediator of cellular radioresistance in vitro. This study aims to compare survivin expression and apoptosis to histomorphologic responses to neoadjuvant radiochemotherapy (RCT) in rectal cancer., Materials and Methods: Thirty-six pre-treatment biopsies were studied. Survivin mRNA and protein expression plus TUNEL staining for apoptosis was performed. Response to treatment was assessed using a 5-point tumour regression grade., Results: Survivin expression was not found to be predictive of response to RCT (p = NS). In contrast, spontaneous apoptosis was significantly (p = 0.0051) associated with subsequent response to RCT. However, no association between survivin expression and levels of apoptosis could be identified., Conclusions: This in vivo study failed to support in vitro studies showing an association between survivin and response to chemotherapy and radiation therapy. These results caution against the translation of the in vitro properties of survivin into a clinical setting.

Although uncommon and often asymptomatic, portal venous thrombosis can have catastrophic consequences for the individual it afflicts, particularly when the process propagates to involve the superior mesenteric vein. Familiarity with the condition's pathogenesis and presentation however permits early diagnosis and allows aggressive conservative management to achieve a successful outcome. Here we describe the successful outcome of such management for a 42-year-old male patient who developed this condition spontaneously.

Although commonly detectable in patients with cirrhosis, rectal varices only infrequently cause significant hematochezia (0.5-3.6%). While they may be expected to resolve with treatment of the concomitant portal hypertension, there is currently no standardized approach to their management in isolation. Therefore many authorities recommend transjugular intrahepatic portosystemic shunting (TIPS) as a means of alleviating otherwise recalcitrant bleeding. Conceptually, however, rectal varices should be as amenable to local therapies as are their counterparts occurring at the esophagogastric junction. In this report, we describe the use of endoscopic banding per ano to alleviate significant rectal bleeding in a patient with poorly controlled portal hypertension. This allowed medical optimisation so that the underlying pathology could be controlled without recourse to TIPS or other means of creating a formal portosystemic shunt.

Introduction: Those who have surmounted the learning curve for laparoscopic colorectal resection state that considerable numbers of highly selected cases should comprise a department's early experience to ensure reliability of technique before routine implementation. The objective of this study was to determine how this advice may interrupt case flow., Methods: Details on all colorectal operations performed in a single institution over a 4-year period were gleaned from a prospectively maintained database. Patient profiles were scrutinised to identify how the application of various published exclusion criteria would impact upon the theoretical completion rates of our proposed learning curve., Results: In total, 317 colorectal resections were performed; 259 operations were for adenocarcinoma (including 100 rectal tumours) while 58 were for benign disease. Of those with malignancy, 25(10%) were obese, 61(24%) had previous intra-abdominal surgery, while 52(20%) were aged over 80 years and 60(23%) were ASA (3/4). Strictest exclusion criteria would halve the number of cases to be commenced laparoscopically. A specialist registrar rotating through the department would have case exposure cut from a mean of 33 to 11 in 6 months under this regimen. Prioritising benign cases in the initial experience as has been recommended by certain groups would mean that, at most, 1.2 cases would be performed every 4 weeks during the learning period., Conclusion: Although our caseload seems sufficient to allow the acquisition of expertise in a timely fashion, procedural flow would be markedly interrupted by stringent pre-selection. A low threshold for initiating the procedure laparoscopically seems a pragmatic way of ensuring departmental confidence through familiarity.

Objective: We investigated whether proteomic analysis of the low molecular weight region of the serum proteome could predict histologic response of locally advanced rectal cancer to neoadjuvant radiochemotherapy (RCT)., Summary Background Data: Proteomic analysis of serum is emerging as a powerful new modality in cancer, in terms of both screening and monitoring response to treatment. No study has yet assessed its ability to predict and monitor the response of rectal cancer to RCT., Methods: Sequential serum samples from 20 patients undergoing RCT were prospectively collected. Time points sampled were as follows: pretreatment, 24/48 hours, 1 week, 2 weeks, 3 weeks, 5 weeks (last day of RCT), and presurgery. Response to treatment was measured using a 5-point tumor regression grade (TRG) based on the degree of residual tumor to fibrosis. All serum samples were analyzed in duplicate using surface-enhanced laser desorption/ionization-time of flight mass spectrometry (SELDI-TOF-MS). Support vector machine (SVM) analysis of spectra was used to generate a predictive algorithm for each time point based on proteins that were maximally differentially expressed between good and poor responders. This algorithm was then tested using leave-one-out cross validation., Results: In total, 230 spectra were generated representing all available time points from 9 good responders (TRG 1+2) and 11 poor responders (TRG 3-5). SVM analysis indicated that changes within the serum proteome at the 24/48 hours time point into treatment provided optimal classification accuracy. In more detail, a cohort of 14 protein peaks were identified that collectively differentiated between good and poor responders, with 87.5% sensitivity and 80% specificity., Conclusions: Serum proteomic analysis may represent an early response predictor in multimodal treatment regimens of rectal cancer. These data suggest that this novel, minimally invasive modality may be a useful adjunct in the multimodal management of rectal cancer, and in the design of future clinical trials.

The development of ultra-intense lasers has facilitated new studies in laboratory astrophysics and high-density nuclear science, including laser fusion. Such research relies on the efficient generation of enormous numbers of high-energy charged particles. For example, laser-matter interactions at petawatt (10(15) W) power levels can create pulses of MeV electrons with current densities as large as 10(12) A cm(-2). However, the divergence of these particle beams usually reduces the current density to a few times 10(6) A cm(-2) at distances of the order of centimetres from the source. The invention of devices that can direct such intense, pulsed energetic beams will revolutionize their applications. Here we report high-conductivity devices consisting of transient plasmas that increase the energy density of MeV electrons generated in laser-matter interactions by more than one order of magnitude. A plasma fibre created on a hollow-cone target guides and collimates electrons in a manner akin to the control of light by an optical fibre and collimator. Such plasma devices hold promise for applications using high energy-density particles and should trigger growth in charged particle optics.

In one surgical unit, 115 patients undergoing cholecystectomy were studied to compare patient recovery, subjective and objective pain experienced and complications after laparoscopic and open cholecystectomy. The data were collected prospectively where allocation to open or laparoscopic cholecystectomy was by consecutive attendance. Laparoscopic cholecystectomy was feasible in 90% of patients presenting with symptomatic gallstones. Compared with the open operation, laparoscopic cholecystectomy was safe with less peroperative and postoperative morbidity, was more cost-effective and was associated with faster patient recovery as documented by less postoperative pain, earlier return to diet, earlier full mobilisation and discharge home. Laparoscopic cholecystectomy is superior to open cholecystectomy and should be available to all patients requiring elective cholecystectomy.

A prospective multicentre study comparing the value of the recently introduced minilaparoscopy with peritoneal lavage in patients with abdominal trauma is in progress. To date 55 patients with blunt abdominal trauma have been entered into the study. Following initial resuscitation, 26 were randomised to peritoneal lavage and 29 to minilaparoscopy performed under intravenous sedation and local anaesthesia. The two groups were comparable with respect to age, sex, incidence of multiple injuries and mortality (2 patients in the lavage group and 1 in the minilaparoscopy group). A negative test was obtained in 15 patients subjected to lavage and 12 patients who underwent minilaparoscopy. A further four patients in the minilaparoscopy group were found to have a minimal static haemoperitoneum. All these patients were treated conservatively and none required surgical intervention on the abdomen. Thus neither investigation carried a false negative rate. A positive test was obtained in 11 patients in the lavage group and significant findings were observed in 13 patients assessed by minilaparoscopy. All these patients were subjected to emergency laparotomy. Absence of significant bleeding or trauma was observed at laparotomy in 3/11 (27%) and 1/13 (8%) in the lavage and minilaparoscopy groups respectively. Although both procedures were highly sensitive for the detection of significant intra-abdominal injury (100%), the specificity was 83% for peritoneal lavage and 94% for minilaparoscopy. The predictive value of a positive minilaparoscopic examination was 92% as opposed to a positive predictive value of 72% for peritoneal lavage.

A helium-neon gas laser has been successfully used in conjunction with an automatic fringe-counting interferometer to measure the length of a meter bar. The agreement obtained was 7 parts in 100 million with respect to the assigned length of the bar.