The impact of low-mode symmetry on inertial fusion energy output in the burning plasma state

Indirect Drive Inertial Confinement Fusion Experiments on the National Ignition Facility (NIF) have achieved a burning plasma state with neutron yields exceeding 170 kJ, roughly 3 times the prior record and a necessary stage for igniting plasmas. The results are achieved despite multiple sources of degradations that lead to high variability in performance. Results shown here, for the first time, include an empirical correction factor for mode-2 asymmetry in the burning plasma regime in addition to previously determined corrections for radiative mix and mode-1. Analysis shows that including these three corrections alone accounts for the measured fusion performance variability in the two highest performing experimental campaigns on the NIF to within error. Here we quantify the performance sensitivity to mode-2 symmetry in the burning plasma regime and apply the results, in the form of an empirical correction to a 1D performance model. Furthermore, we find the sensitivity to mode-2 determined through a series of integrated 2D radiation hydrodynamic simulations to be consistent with the experimentally determined sensitivity only when including alpha-heating.

Design of the first fusion experiment to achieve target energy gain G>1

In this work we present the design of the first controlled fusion laboratory experiment to reach target gain G>1 N221204 (5 December 2022) [Phys. Rev. Lett. 132, 065102 (2024)10.1103/PhysRevLett.132.065102], performed at the National Ignition Facility, where the fusion energy produced (3.15 MJ) exceeded the amount of laser energy required to drive the target (2.05 MJ). Following the demonstration of ignition according to the Lawson criterion N210808, experiments were impacted by nonideal experimental fielding conditions, such as increased (known) target defects that seeded hydrodynamic instabilities or unintentional low-mode asymmetries from nonuniformities in the target or laser delivery, which led to reduced fusion yields less than 1 MJ. This Letter details design changes, including using an extended higher-energy laser pulse to drive a thicker high-density carbon (also known as diamond) capsule, that led to increased fusion energy output compared to N210808 as well as improved robustness for achieving high fusion energies (greater than 1 MJ) in the presence of significant low-mode asymmetries. For this design, the burnup fraction of the deuterium and tritium (DT) fuel was increased (approximately 4% fuel burnup and a target gain of approximately 1.5 compared to approximately 2% fuel burnup and target gain approximately 0.7 for N210808) as a result of increased total (DT plus capsule) areal density at maximum compression compared to N210808. Radiation-hydrodynamic simulations of this design predicted achieving target gain greater than 1 and also the magnitude of increase in fusion energy produced compared to N210808. The plasma conditions and hotspot power balance (fusion power produced vs input power and power losses) using these simulations are presented. Since the drafting of this manuscript, the results of this paper have been replicated and exceeded (N230729) in this design, together with a higher-quality diamond capsule, setting a new record of approximately 3.88MJ of fusion energy and fusion energy target gain of approximately 1.9.

Biopsies for Soft-Tissue Sarcoma of the Hand: Dangers, Hazards, and Outcomes

INTRODUCTION

Excisional biopsies for soft-tissue sarcoma (STS) of the hand are commonly done outside of sarcoma centers and can compromise incorporation of the biopsy site into standard limb salvage or amputation flaps. We sought to identify risk factors for these suboptimal biopsies.

METHODS

We analyzed prospective data on all patients (N = 109) who underwent definitive resection of primary STS of the hand between 1995 and 2019 at our institution. Biopsies were classified by type (excisional vs. incisional/needle), whether they were done before referral, and whether the incision could be incorporated into standard limb salvage or amputation flaps (ILS biopsies) or not (NILS biopsies). Analyses examined potential predictors of NILS biopsies and whether outcomes differed by biopsy type.

RESULTS

Biopsies done before referral (N = 91) were more likely to be excisional (79% vs. 17%). Excisional biopsies were associated with smaller tumor size (median, 2.0 vs. 3.15 cm; P = 0.025) and longer time to first intervention (1.88 vs. 1.17 months; P = 0.001). Forty-eight percent of excisional and 29% of incisional biopsy sites required soft-tissue coverage at the time of definitive surgery ( P = 0.07). Biopsy type was not associated with Musculoskeletal Tumor Society score or need for amputation. Risk factors for NILS biopsies included larger tumor size, deep tumor, and excisional biopsy. High-risk areas for NILS biopsies included the carpal tunnel, volar wrist, first webspace, radial palm, and proximal thumb. NILS biopsies were associated with positive margins, need for soft-tissue coverage, and lower Musculoskeletal Tumor Society scores.

DISCUSSION

This study informs referral guidelines for patients with STS of the hand. Patients with tumors that are deep, large, or in high-risk locations should be referred to a sarcoma center before biopsy. If that is not possible, incisional biopsy in line with standard resection incisions or radiology-guided core needle biopsy is preferable to excisional biopsy.

TYPE OF STUDY

Prognostic study.

LEVEL OF EVIDENCE

Level II.

Natural mutations of human XDH promote the nitrite (NO2-)-reductase capacity of xanthine oxidoreductase: A novel mechanism to promote redox health?

Several rare genetic variations of human XDH have been shown to alter xanthine oxidoreductase (XOR) activity leading to impaired purine catabolism. However, XOR is a multi-functional enzyme that depending upon the environmental conditions also expresses oxidase activity leading to both O2·- and H2O2 and nitrite (NO2-) reductase activity leading to nitric oxide (·NO). Since these products express important, and often diametrically opposite, biological activity, consideration of the impact of XOR mutations in the context of each aspect of the biochemical activity of the enzyme is needed to determine the potential full impact of these variants. Herein, we show that known naturally occurring hXDH mutations do not have a uniform impact upon the biochemical activity of the enzyme in terms of uric acid (UA), reactive oxygen species (ROS) and nitric oxide ·NO formation. We show that the His1221Arg mutant, in the presence of xanthine, increases UA, O2·- and NO generation compared to the WT, whilst the Ile703Val increases UA and ·NO formation, but not O2·-. We speculate that this change in the balance of activity of the enzyme is likely to endow those carrying these mutations with a harmful or protective influence over health that may explain the current equipoise underlying the perceived importance of XDH mutations. We also show that, in presence of inorganic NO2-, XOR-driven O2·- production is substantially reduced. We suggest that targeting enzyme activity to enhance the NO2--reductase profile in those carrying such mutations may provide novel therapeutic options, particularly in cardiovascular disease.

Memory of social experience affects female fecundity via perception of fly deposits

Background

Animals can exhibit remarkable reproductive plasticity in response  to their social surroundings, with profound fitness consequences. The presence of same-sex conspecifics can signal current or future expected competition for resources or mates. Plastic responses to elevated sexual competition caused by exposure to same-sex individuals have been well-studied in males. However, much less is known about such plastic responses in females, whether this represents sexual or resource competition, or if it leads to changes in investment in mating behaviour and/or reproduction. Here, we used Drosophila melanogaster to measure the impact of experimentally varying female exposure to other females prior to mating on fecundity before and after mating. We then deployed physical and genetic methods to manipulate the perception of different social cues and sensory pathways and reveal the potential mechanisms involved.

Results

The results showed that females maintained in social isolation prior to mating were significantly more likely to retain unfertilised eggs before mating, but to show the opposite and lay significantly more fertilised eggs in the 24h after mating. More than 48h of exposure to other females was necessary for this social memory response to be expressed. Neither olfactory nor visual cues were involved in mediating fecundity plasticity—instead, the relevant cues were perceived through direct contact with the non-egg deposits left behind by other females.

Conclusions

The results demonstrate that females show reproductive plasticity in response to their social surroundings and can carry this memory of their social experience forward through mating. Comparisons of our results with previous work show that the nature of female plastic reproductive responses and the cues they use differ markedly from those of males. The results emphasise the deep divergence in how each sex realises its reproductive success.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12915-022-01438-5.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

The Effect of Standardized Perioperative Patient Education on Opioid Use After Minor Soft Tissue Procedures Distal to the Wrist

PURPOSE

Several studies have explored opioid consumption and opioid prescriber education for upper extremity procedures; however, less literature has focused on patient-centered interventions and their impact on opioid consumption after surgery. The purpose of this study was to create a standardized perioperative patient education program regarding postoperative pain management after hand surgery and to determine if it could reduce opioid use after hand surgery.

METHODS

Patients scheduled to undergo elective outpatient hand surgery comprising minor soft tissue procedures at and distal to the wrist were randomized to receive pain management education or standard care. Before the surgery, all patients viewed a webinar with instructions for participation, whereas the education group received an additional 10 minutes of education on postoperative pain management and a pain management reference card for review after the surgery. All patients completed a postoperative daily log documenting the number of opioids consumed, other pain management modalities used, and pain scores. The primary outcome of the number of opioid pills consumed by the patients was compared between the groups. We constructed a linear regression model to determine the risk factors for postoperative opioid use after surgery.

RESULTS

One hundred seventy-four patients completed the study (n = 90 education group; n = 84 standard care group). Patients in the education group took significantly fewer opioid pills (median = 0, range 0-13) than those in the standard care group (median = 0.5, range 0-40). A linear regression model showed that average week-1 pain (B = 0.93; 95% confidence interval, 0.56-1.3) and the number of pills prescribed (B = 0.12; 95% confidence interval, 0.017-0.22) were predictive of greater opioid use.

CONCLUSIONS

Perioperative patient education significantly reduced postoperative opioid use following a minor soft tissue hand surgery, with greater than 70% of the patients taking no opioids.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

Prospective Randomized Study Examining Preoperative Opioid Counseling on Postoperative Opioid Consumption after Upper Extremity Surgery

Background: Rates of opioid addiction and overdose continue to climb in the United States, increasing pressure on prescribers to identify solutions to decrease postoperative opioid consumption. Hand and upper extremity surgeries are high-volume surgeries with a predilection for inadvertent overprescribing. Recent investigations have shown that preoperative opioid counseling may decrease postoperative opioid consumption. In order to test this hypothesis, a prospective randomized trial was undertaken to determine the effect of preoperative opioid counseling on postoperative opioid consumption. Methods: Eligible patients undergoing outpatient upper extremity surgery were randomized to either receive preoperative opioid counseling or to receive no counseling. Surgeons were blinded to their patient's counseling status. Preoperatively, patient demographics, surgical and prescription details were recorded. Postoperatively, patients' pain experience including opioid consumption, pain levels, and satisfaction was recorded. Results: There were 131 total patients enrolled, with 62 in the counseling group and 69 in the control group. Patients receiving counseling consumed 11.8 pills compared to 17.4 pills in the control group (P = .007), which translated to 93.7 Morphine Equivalent Units (MEU) in the counseling group compared to 143.2 MEU in the control group (P = .01). There was no difference in pain scores at any time point between groups. Among all study patients a total of 3767 opioid pills were prescribed with approximately 50% left unused. Conclusion: Patients receiving preoperative counseling consumed significantly fewer opioids postoperatively. Inadvertant overprescribing remains high. Routine use of preoperative counseling should be implemented along with prescribing fewer opioids overall to prevent overprescribing.

Hematoma following total elbow arthroplasty: incidence, management, and outcomes

INTRODUCTION

This study investigates the incidence, risk factors for, and clinical outcomes of hematoma following total elbow arthroplasty.

METHODS

We retrospectively reviewed patient and surgical characteristics as predictors of post-operative hematoma in 382 total elbow arthroplasty (196 primary, 157 revision, and 29 conversion) between May 2004 and February, 2017. For comparison of outcomes, cases were matched (1:2) with controls by age, gender, type of surgery, and surgical indication.

RESULTS

Nineteen post-operative hematomas (5.0%; 19/382) were identified. Total elbow arthroplasty for post-traumatic arthritis (6.7%; 4/60), aseptic loosening (7.9%; 3/38), sequelae of periprosthetic joint infection (6.1%; 5/81), and non-union (28.6%; 2/7) had the highest incidence of hematoma. Clinic aspiration and compressive wrap was performed in 14 patients and avoided a return to the operating room in 78.6% (11/14). Seven patients (36.8%) required a return to the operating room, of which five (71.4%) had positive cultures and required treatment for prosthetic joint infection. Compared to the matched controls, hematoma formation predicted a higher rate of reoperation (36.8% versus 7.9%; p = 0.007) and a higher rate of subsequent prosthetic joint infection (35.7% versus 0%; p = 0.008).

CONCLUSION

Hematoma formation is associated with both prosthetic joint infection and return to the operating room after total elbow arthroplasty. Strategies to prevent hematoma formation after total elbow arthroplasty may reduce complication rates.

The Effect of Preoperative Opioid Education on Opioid Consumption After Outpatient Orthopedic Surgery: A Prospective Randomized Trial

Pain management and opioid consumption following outpatient orthopedic surgery may be influenced by several variables, including knowledge of safe opioid use. A prospective randomized study was undertaken to understand the effect of preoperative opioid education on opioid consumption following outpatient orthopedic surgeries. A total of 237 patients undergoing outpatient orthopedic surgeries were prospectively randomized to receive preoperative opioid education or not. Postoperative data collected included the number of pills taken, daily visual analog scale (VAS) pain scores, adverse events, and attitude toward the pain experience. A total of 107 patients were randomized to receive preoperative education and 130 to not receive preoperative education. On average, 27 pills were prescribed to each patient. The preoperative opioid education group consumed significantly fewer opioids (6 pills) when compared with the group not receiving education (12 pills) (P<.05). The findings were the same with upper and lower extremity surgeries. Overall, the 2 groups of patients had similar daily VAS scores and were satisfied with their postoperative pain experience irrespective of opioid education. Of the total opioid pills prescribed during the study, only 46% were ultimately consumed. Preoperative education significantly reduced the number of prescription opioid pills and total morphine equivalents consumed by patients in the period following outpatient orthopedic surgery, with no negative effects on pain experience. This finding was consistent in both upper and lower extremity surgery. Approximately twice the number of opioids were prescribed than ultimately consumed by patients. [Orthopedics. 2021;44(2):123-127.].

Slow and Fast Light in Plasma Using Optical Wave Mixing

Slow and fast light, or large changes in the group velocity of light, have been observed in a range of optical media, but the fine optical control necessary to induce an observable effect has not been achieved in a plasma. Here, we describe how the ion-acoustic response in a fully ionized plasma can produce large and measurable changes in the group velocity of light. We show the first experimental demonstration of slow and fast light in a plasma, measuring group velocities between 0.12c and -0.34c.

Prospective Randomized Study Evaluating the Effects of Preoperative Opioid Counseling on Postoperative Opioid Use after Outpatient Lower Extremity Orthopaedic Surgery

The objective of this study was to investigate the effect of standardized preoperative opioid counseling on postoperative opioid consumption for patients undergoing outpatient lower extremity orthopaedic surgery. Participating patients undergoing elective outpatient lower extremity orthopaedic surgery were randomized to either receive preoperative opioid counseling or not receive counseling (control group). Counseling was delivered via a five-minute pre-recorded standardized video preoperatively. Postoperatively, patients in both groups were queried for their postoperative pain experience, opioid consumption, non-opioid medication consumption, and any adverse effects related to their pain management experience. A total of 107 patients were studied, with 45 in the counseling group and 62 in the control group. Patients that received preoperative opioid counseling consumed on average 6.5 opioid pills postoperatively; the control group consumed 12.4 opioid pills (p = 0.008). Preoperative opioid counseling resulted in a statistically significant reduction in postoperative opioid consumption after outpatient lower extremity orthopaedic surgery. (Journal of Surgical Orthopaedic Advances 30(1):002-006, 2021).

Pyogenic Flexor Tenosynovitis: Evaluation and Treatment Strategies

Pyogenic flexor tenosynovitis (PFT) is a common closed-space infection of the flexor tendon sheaths of the hand, which remains one of the most challenging problems facing hand surgeons. PFT goes by several names including septic or suppurative flexor tenosynovitis. Adequate treatment requires timely diagnosis and often prompt surgical treatment. However, despite prompt treatment, and regardless of the protocol used, complication rates as high as 38% have been reported in the literature. Moreover, even with successful eradication of the infection, a significant proportion of patients will suffer from continuing pain, swelling, stiffness, loss of composite flexion, weakness, and recurrence potentially requiring amputation. This review will focus on current evidence-based antimicrobial and surgical treatment strategies to maximize treatment outcomes.

How are Electronic Health Records Associated with Provider Productivity and Billing in Orthopaedic Surgery?

BACKGROUND

Electronic health records (EHRs) have become ubiquitous in orthopaedics. Although they offer certain benefits, they have been cited as a factor that can contribute to provider burnout. Little is known about the degree to which EHR adoption is associated with provider and practice characteristics or outpatient and surgical volume.

QUESTIONS/PURPOSES

(1) What was the rate of EHR adoption in orthopaedics and how are physician and practice characteristics associated with adoption? (2) How is EHR adoption related to outpatient productivity? (3) How is EHR adoption associated with surgical volume?

METHODS

We conducted this retrospective analysis by linking three publicly available Medicare databases, which we chose for their reliability in reporting because they are provided by a government-funded entity. We included providers in the 2016 Physician Compare dataset who reported a primary specialty of orthopaedic surgery. The EHR adoption status for these providers between 2011 and 2016 was determined using the Meaningful Use Eligible Professional public use files, which we chose to standardize both adoption and usage of EHRs. Provider characteristics, from the Physician Compare dataset, were compared between non-adopters, early adopters (who adopted EHR in 2011 and 2012), and late adopters (2016) using a multivariate logistic analysis, due to the binary nature of the dependent variable (adoption). To measure productivity and billing, we used the 2012 and 2016 Medicare Utilization and Payment datasets. To measure productivity before and after EHR adoption, we compared the number of services for select Current Procedural Terminology codes between 2012 and 2016 for providers who first adopted EHR in 2013, and performed the same comparison for non-adopters for the same years. Paired t-tests were used where volume in 2012 and 2016 were being compared, and multivariate analysis was performed.

RESULTS

By 2016, 10,904 of 21,484 orthopaedic providers (51%) had adopted EHRs, with an increase from 8% to 46% during the incentive phase (2011 to 2014) and an increase from 44% to 51% during the penalty phase (2015 to 2016). After analyzing factors associated with adoption, it was most notable that for every additional year since graduation, the odds of adopting EHR later increased by 4.14 (95% confidence interval 4.00 to 4.33; p < 0.001). After adoption, providers who adopted EHRs increased the mean number of Medicare outpatient visits per year from 439 to 470 (mean difference, increase of 31 procedures [95% CI 24 to 39]; p < 0.001), and providers who did not use EHRs decreased from 378 to 368 visits per year (median difference, decrease of 10 procedures [95% CI 8.0 to 12.0]; p < 0.001). EHR was not associated with billing for Level 4-5 visits, after adjusting for practice size and pre-adoption volumes (p = 0.32; R = 0.51). EHR adoption was not associated with surgical volume for 10 of 11 common orthopaedic procedures. However, two additional TKA procedures annually could be attributed to EHR adoption, when compared with non-adopters (p = 0.03; R = 0.65). After adoption, orthopaedic surgeons increased their annual TKA volume from 42 to 48 (mean difference, increase of 6 [95% CI 4.0 to 7.0]; p < 0.001), while non-adopting orthopaedic surgeons increased their annual surgical volume for TKA from 28 to 30 (median difference, increase of 2 [95% CI 2.0 to 4.0]; p < 0.001).

CONCLUSIONS

In orthopaedics, the Health Information Technology for Economic and Clinical Health (HITECH) Act resulted in approximately half of self-reported orthopaedic surgeons adopting EHR from 2011 to 2016. Considering the high cost of most EHRs and the substantial investment in adoption incentives, this adoption rate may not be sufficient to fully realize the objectives of the HITECH Act. Diffusion of technology is a vast field of study within social theory. Prominent sociologist Everett M. Rogers details its complexity in Diffusion of Innovations. Diffusion of technology is impacted by factors such as the possibility to sample the innovation without commitment, opinion leadership, and observability of results in a peer network, to name a few. Incorporating these principles, where appropriate, into a more focused action plan may facilitate technological diffusion for future innovations. Lastly, EHR adoption was not associated with higher-level billing or surgical volume. This might suggest that EHRs have not had a meaningful clinical benefit, but this needs to be further investigated by relating these trends to patient outcomes or other quality measures.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Pyogenic Flexor Tenosynovitis: Evaluation and Treatment Strategies

Pyogenic flexor tenosynovitis (PFT)is a potentially devastating closed-space infection of the flexor tendon sheath of the hand that can result in considerable morbidity. Management of PFT, regardless of the pathogen, includes prompt administration of empirical intravenous antibiotics and often surgical treatment. However, currently, there is no standardized treatment algorithm for PFT in regards to the need for, timing, or type of surgical treatment. Many utilize a combination of surgical decompression and sheath irrigation. However, despite prompt treatment, and regardless of the protocol used, complication rates can be high, leading to impaired function and even amputation of the affected digit. Further research is needed to elucidate the role of local antibiotics and corticosteroids in treating this condition and potentially preventing the morbid outcomes that are currently seen. This paper reviews the background, microbiology, and treatment options and controversies surrounding PFT.

Elevated Radiation Exposure Associated With Above Surface Flat Detector Mini C-Arm Use

Background: This study aims to test the hypothesis that: (1) radiation exposure is increased with the intended use of Flat Surface Image Intensifier (FSII) units above the operative surface compared with the traditional below-table configuration; (2) this differential increases in a dose-dependent manner; and (3) radiation exposure varies with body part and proximity to the radiation source. Methods: A surgeon mannequin was seated at a radiolucent hand table, positioned for volar distal radius plating. Thermoluminescent dosimeters measured exposure to the eyes, thyroid, chest, hand, and groin, for 1- and 15-minute trials from a mini C-arm FSII unit positioned above and below the operating surface. Background radiation was measured by control dosimeters placed within the operating theater. Results: At 1-minute of exposure, hand and eye dosages were significantly greater with the flat detector positioned above the table. At 15-minutes of exposure, hand radiation dosage exceeded that of all other anatomic sites with the FSII in both positions. Hand exposure was increased in a dose-dependent manner with the flat detector in either position, whereas groin exposure saw a dose-dependent only with the flat detector beneath the operating table. Conclusions: These findings suggest that the surgeon's hands and eyes may incur greater radiation exposure compared with other body parts, during routine mini C-arm FSII utilization in its intended position above the operating table. The clinical impact of these findings remains unclear, and future long-term radiation safety investigation is warranted. Surgeons should take precautions to protect critical body parts, particularly when using FSII technology above the operating with prolonged exposure time.

Genomic sequence analysis reveals diversity of Australian Xanthomonas species associated with bacterial leaf spot of tomato, capsicum and chilli

Background

The genetic diversity in Australian populations of Xanthomonas species associated with bacterial leaf spot in tomato, capsicum and chilli were compared to worldwide bacterial populations. The aim of this study was to confirm the identities of these Australian Xanthomonas species and classify them in comparison to overseas isolates. Analysis of whole genome sequence allows for the investigation of bacterial population structure, pathogenicity and gene exchange, resulting in better management strategies and biosecurity.

Results

Phylogenetic analysis of the core genome alignments and SNP data grouped strains in distinct clades. Patterns observed in average nucleotide identity, pan genome structure, effector and carbohydrate active enzyme profiles reflected the whole genome phylogeny and highlight taxonomic issues in X. perforans and X. euvesicatoria. Circular sequences with similarity to previously characterised plasmids were identified, and plasmids of similar sizes were isolated. Potential false positive and false negative plasmid assemblies were discussed. Effector patterns that may influence virulence on host plant species were analysed in pathogenic and non-pathogenic xanthomonads.

Conclusions

The phylogeny presented here confirmed X. vesicatoria, X. arboricola, X. euvesicatoria and X. perforans and a clade of an uncharacterised Xanthomonas species shown to be genetically distinct from all other strains of this study. The taxonomic status of X. perforans and X. euvesicatoria as one species is discussed in relation to whole genome phylogeny and phenotypic traits. The patterns evident in enzyme and plasmid profiles indicate worldwide exchange of genetic material with the potential to introduce new virulence elements into local bacterial populations.

Electronic supplementary material

The online version of this article (10.1186/s12864-019-5600-x) contains supplementary material, which is available to authorized users.

Theory and measurements of convective Raman side scatter in inertial confinement fusion experiments

Raman side scatter, whereby scattered light is resonant while propagating perpendicularly to a density gradient in a plasma, was identified experimentally in planar-target experiments at the National Ignition Facility at intensities orders of magnitudes below the threshold for absolute instability. We have derived a new theoretical description of convective Raman side scatter below the absolute threshold, validated by numerical simulations. We show that inertial confinement fusion experiments at full ignition scale, i.e., with mm-scale spot sizes and density scale lengths, are prone to increased coupling losses from Raman side scatter as the instability can extend from the absolute regime near the quarter-critical density to the convective regime at lower electron densities.

Mini C-Arm Fluoroscopy: Does Its Configuration Matter for Radiation Exposure to the Surgeon?

BACKGROUND

The risk of occupational radiation exposure to the surgeon associated with the use of a mini C-arm has yet to reach a wide consensus. Using a distal radius fracture surgery model, we tested the hypothesis that radiation exposure to the surgeon's critical body parts is independent of mini C-arm configuration.

METHODS

An anthropomorphic mannequin (representing the upper body of a 60" male surgeon) was seated at a hand table as if operating on a volar-plated wrist Sawbone model. Thermoluminescent dosimeters measured radiation exposure to the surgeon's eyes, thyroid, chest, hand, and groin from a mini C-arm fluoroscopy unit in 3 commonly used configurations: vertical (source above table), inverted (source below table), and horizontal (with beam parallel to table surface). The fluoroscope scanned the wrist model for 15 continuous minutes in triplicate for each orientation.

RESULTS

Radiation to the hand was significantly greatest in all mini C-arm positions compared with all other anatomic sites irrespective of C-arm position. Hand radiation exposure was greatest in the horizontal position (2887.09 mrem), versus the vertical and inverted positions (59.79 mrem, 31.10 mrem, P < .001). Eye radiation exposure was significantly greater in the inverted position (2.33 mrem) compared with the vertical (0.67 mrem, P = .024), and horizontal positions (0.33 mrem, P = .012). No significant difference in radiation exposure was found at the thyroid, chest, and groin sites, at each of the 3 C-arm configurations.

CONCLUSIONS

The model's hand received almost 1000 times more radiation exposure than all other anatomic sites with statistically greatest radiation exposure sustained in the horizontal position. Eye radiation exposure with the C-arm in the inverted position (below the table) was also significantly greater.

An Evaluation of the Reliability of Wrist Arthroscopy in the Assessment of Tears of the Triangular Fibrocartilage Complex

PURPOSE

Wrist arthroscopy is generally considered the reference standard in the diagnosis of triangular fibrocartilage complex (TFCC) injuries. There is a paucity of data examining the reliability of wrist arthroscopy as a diagnostic modality for TFCC injuries. The goal of this study was to evaluate the interobserver and intraobserver reliability of the diagnosis of TFCC pathology during wrist arthroscopy.

METHODS

Twenty-five intraoperative digital videos were captured by the senior author during diagnostic and surgical arthroscopy of the wrist joint for known or suspected articular pathology. The senior author (P.K.B.) confirmed TFCC resilience on visual inspection and ballottement (trampoline effect) to make the diagnosis. Two videos were excluded for poor quality and inadequate visualization. Three hand surgeons subsequently reviewed the remaining 23 videos in a blinded fashion at 2 time points separated by 4 weeks. The reviewers determined if the trampoline test was positive and if a TFCC tear was present. Tears were classified using a morphologic classification. Statistical measures of reliability including percentage agreement and κ coefficients were calculated.

RESULTS

Agreement between observers for the presence or absence of a tear was 66.7%. The average intraobserver agreement regarding the presence or absence of a tear was 67.4% The kappa value for interobserver agreement was 0.33, whereas the intrarater agreement was 0.88. The 3 reviewers identified an average of 11.3 positive trampoline tests. Agreement between observers for a positive trampoline test was 65.2%. The average percentage of intraobserver agreement regarding a positive trampoline test was 49.3%. In cases where all 3 reviewers agreed on the presence of a TFCC tear, the agreement regarding tear location was 76.6%.

CONCLUSIONS

Wrist arthroscopy remains instrumental in the treatment of TFCC tears. However, given that inter-rater reliability in the assessment of these tears is probably too low, reconsideration should be given to arthroscopy as the reference standard in the diagnosis of these tears.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic III.

Origins and Scaling of Hot-Electron Preheat in Ignition-Scale Direct-Drive Inertial Confinement Fusion Experiments

Planar laser-plasma interaction (LPI) experiments at the National Ignition Facility (NIF) have allowed access for the first time to regimes of electron density scale length (∼500 to 700  μm), electron temperature (∼3 to 5 keV), and laser intensity (6 to 16×10^{14}  W/cm^{2}) that are relevant to direct-drive inertial confinement fusion ignition. Unlike in shorter-scale-length plasmas on OMEGA, scattered-light data on the NIF show that the near-quarter-critical LPI physics is dominated by stimulated Raman scattering (SRS) rather than by two-plasmon decay (TPD). This difference in regime is explained based on absolute SRS and TPD threshold considerations. SRS sidescatter tangential to density contours and other SRS mechanisms are observed. The fraction of laser energy converted to hot electrons is ∼0.7% to 2.9%, consistent with observed levels of SRS. The intensity threshold for hot-electron production is assessed, and the use of a Si ablator slightly increases this threshold from ∼4×10^{14} to ∼6×10^{14}  W/cm^{2}. These results have significant implications for mitigation of LPI hot-electron preheat in direct-drive ignition designs.

Anterior Talofibular Ligament Abnormalities on Routine Magnetic Resonance Imaging of the Ankle

Category:

Ankle, Sports, Trauma

Introduction/Purpose:

The anterior talofibular ligament (ATFL) is one of the most commonly injured structures of the lower extremity after an ankle sprain. Evidence of remote injury to this structure is frequently encountered on magnetic resonance imaging (MRI) of the ankle, with uncertain clinical significance. Previous studies in the orthopaedic literature have discussed the prevalence of abnormal MRI findings in asymptomatic patients, most notably with regards to the spine and shoulder. More recently, a study on the prevalence of peroneal tendon abnormalities on routine MRI of the ankle was published. However, to our knowledge, no such study exists for the ATFL. The purpose of this study is to determine the prevalence of abnormal findings of the ATFL on MRI in asymptomatic individuals.

Methods:

All foot and ankle MRIs performed at our institution over a 4-month period were considered for inclusion in our study. Studies were excluded if performed on patients with documented ankle inversion injuries, ankle sprains, lateral ankle trauma, tenderness over the ATFL, or ankle instability. A total of 320 MRIs were eligible for inclusion. The integrity of the ATFL was noted in addition to the primary pathology.

Results:

The median age of the patients included in this study was 51 years with 203 females (63%) and 117 males (37%). One hundred eighteen (37%) of the 320 MRIs demonstrated some ATFL pathology. The most commonly encountered ATFL pathologies were thickening (38%), chronic tear (35%), attenuation (25%) and acute tear (2%).

Conclusion:

The results of this study demonstrate that a sizeable percentage of asymptomatic individuals (37%) will have ATFL abnormalities on magnetic resonance imaging of the foot and ankle. This study can have important clinical implications for patients who present with concerning MRI findings that do not correlate clinically. Based on our results, orthopaedic surgeons or any other physician providing musculoskeletal care can provide counseling and reassurance to patients who present with ATFL pathology on MRI but an absence of clinical findings. Much like MRI of the shoulder or spine, abnormalities must be correlated with the clinical exam.

Longitudinal and Transverse Instability of Ion Acoustic Waves

Ion acoustic waves are found to be susceptible to at least two distinct decay processes. Which process dominates depends on the parameters. In the cases examined, the decay channel where daughter modes propagate parallel to the mother mode is found to dominate at larger amplitudes, while the decay channel where the daughter modes propagate at angles to the mother mode dominates at smaller amplitudes. Both decay processes may occur simultaneously and with onset thresholds below those suggested by fluid theory, resulting in the eventual multidimensional collapse of the mother mode to a turbulent state.

Variation in the post-mating fitness landscape in fruit flies

Sperm competition is pervasive and fundamental to determining a male's overall fitness. Sperm traits and seminal fluid proteins (Sfps) are key factors. However, studies of sperm competition may often exclude females that fail to remate during a defined period. Hence, the resulting data sets contain fewer data from the potentially fittest males that have most success in preventing female remating. It is also important to consider a male's reproductive success before entering sperm competition, which is a major contributor to fitness. The exclusion of these data can both hinder our understanding of the complete fitness landscapes of competing males and lessen our ability to assess the contribution of different determinants of reproductive success to male fitness. We addressed this here, using the Drosophila melanogaster model system, by (i) capturing a comprehensive range of intermating intervals that define the fitness of interacting wild-type males and (ii) analysing outcomes of sperm competition using selection analyses. We conducted additional tests using males lacking the sex peptide (SP) ejaculate component vs. genetically matched (SP+ ) controls. This allowed us to assess the comprehensive fitness effects of this important Sfp on sperm competition. The results showed a signature of positive, linear selection in wild-type and SP+ control males on the length of the intermating interval and on male sperm competition defence. However, the fitness surface for males lacking SP was distinct, with local fitness peaks depending on contrasting combinations of remating intervals and offspring numbers. The results suggest that there are alternative routes to success in sperm competition and provide an explanation for the maintenance of variation in sperm competition traits.

Prospective Evaluation of Opioid Consumption Following Carpal Tunnel Release Surgery

Background: Postoperative pain management and opioid consumption following carpal tunnel release (CTR) surgery may be influenced by many variables. To understand factors affecting opioid consumption, a prospective study was undertaken with the hypothesis that CTR performed under local anesthesia (wide awake local anesthesia with no tourniquet [WALANT]) would result in increased opioid consumption postoperatively compared with cases performed under sedation. Methods: All patients undergoing open CTR surgery were consecutively enrolled over a 6-month period. Information collected included patient demographics, surgical technique, amount and type of narcotic prescribed, number of pills taken, and type of anesthesia. Results: 277 patients were enrolled (56% women, 44% men). On average, 21 pills were prescribed, and 4.3 pills (median = 2) were consumed. There was no difference in consumption between patients who received WALANT (78 cases) versus (198 cases) sedation (4.9 vs 3.9 pills, respectively) (P = .22). There was no difference in opioid consumption based on insurance type (P = .47) or type of narcotic (P = .85). However, more men consumed no opioids (47%) compared with women (36%) (P < .05) and older patients consumed less than younger patients (P < .05). Conclusions: Opioid consumption following CTR is more influenced by age and gender, and less influenced by anesthesia type, insurance type, or the type of opioid prescribed. Many more opioids were prescribed than needed, on an average of 5:1. Many patients, particularly older patients, do not require any opioid analgesia after CTR.

Resource limitation and responses to rivals in males of the fruit fly Drosophila melanogaster

Diet has a profound direct and indirect effect on reproductive success in both sexes. Variation in diet quality and quantity can significantly alter the capacity of females to lay eggs and of males to deliver courtship. Here, we tested the effect of dietary resource limitation on the ability of male Drosophila melanogaster to respond adaptively to rivals by extending their mating duration. Previous work carried out under ad libitum diet conditions showed that males exposed to rivals prior to mating significantly extend mating duration, transfer more ejaculate proteins and achieve higher reproductive success. Such adaptive responses are predicted to occur because male ejaculate production may be limited. Hence, ejaculate resources require allocation across different reproductive bouts, to balance current vs. future reproductive success. However, when males suffer dietary limitation, and potentially have fewer reproductive resources to apportion, we expect adaptive allocation of responses to rivals to be minimized. We tested this prediction and found that males held on agar‐only diets for 5–7 days lost the ability to extend mating following exposure to rivals. Interestingly, extended mating was retained in males held on low yeast/sugar: no sugar/yeast diet treatments, but was mostly lost when males were maintained on ‘imbalanced’ diets in which there was high yeast: no sugar and vice versa. Overall, the results show that males exhibit adaptive responses to rivals according to the degree of dietary resource limitation and to the ratio of individual diet components.

High Power Dynamic Polarization Control Using Plasma Photonics

We report the first experimental demonstration of a plasma wave plate based on laser-induced birefringence. An elliptically polarized input was converted into a nearly ideal circularly polarized beam using an optical system composed of a second laser beam and a plasma. The results are in excellent agreement with linear theory and three-dimensional simulations up to phase delays exceeding π/4, thus establishing the feasibility of laser-plasma photonic devices that are ultrafast, damage-resistant, and easily tunable.

Microguards and micromessengers of the genome

The regulation of gene expression is of fundamental importance to maintain organismal function and integrity and requires a multifaceted and highly ordered sequence of events. The cyclic nature of gene expression is known as 'transcription dynamics'. Disruption or perturbation of these dynamics can result in significant fitness costs arising from genome instability, accelerated ageing and disease. We review recent research that supports the idea that an important new role for small RNAs, particularly microRNAs (miRNAs), is in protecting the genome against short-term transcriptional fluctuations, in a process we term 'microguarding'. An additional emerging role for miRNAs is as 'micromessengers'-through alteration of gene expression in target cells to which they are trafficked within microvesicles. We describe the scant but emerging evidence that miRNAs can be moved between different cells, individuals and even species, to exert biologically significant responses. With these two new roles, miRNAs have the potential to protect against deleterious gene expression variation from perturbation and to themselves perturb the expression of genes in target cells. These interactions between cells will frequently be subject to conflicts of interest when they occur between unrelated cells that lack a coincidence of fitness interests. Hence, there is the potential for miRNAs to represent both a means to resolve conflicts of interest, as well as instigate them. We conclude by exploring this conflict hypothesis, by describing some of the initial evidence consistent with it and proposing new ideas for future research into this exciting topic.

Beyond the gain exponent: Effect of damping, scale length, and speckle length on stimulated scatter

Three-dimensional wave propagation simulations and experiments show that the gain exponent, an often used metric to assess the likelihood of stimulated Brillouin scatter, is insufficient and must be augmented with another parameter, Nr, the ratio of the resonance length, Lres, to the laser speckle length. The damping rate of ion acoustic waves, ν, and thus Lres, which is proportional to ν, are easily varied with plasma species composition, e.g., by varying the ratio of hydrogen and carbon ions. As Nr decreases, stimulated Brillouin scattering increases despite the same gain exponent.

The incidence and patterns of hardware failure after separation surgery in patients with spinal metastatic tumors

BACKGROUND CONTEXT

Spine metastases occur frequently in patients with cancer. A variety of surgical approaches, including anterior transcavitary, lateral extracavitary, posterolateral, and/or combined techniques are used for spinal cord decompression and restoration of spinal stability. The incidence of symptomatic hardware failure is unknown for the majority of these approaches.

PURPOSE

The purpose of this study was to determine the incidence of symptomatic hardware failure and the associated risk factors in patients with metastatic epidural spinal cord compression (MESCC).

STUDY DESIGN/SETTING

This was a retrospective study.

PATIENT SAMPLE

The current series analyzes a cohort of 318 patients who underwent separation surgery, which involves single-stage posterolateral decompression and posterior segmental instrumentation for MESCC.

OUTCOME MEASURES

The event of interest was hardware failure; the competing event was death resulting from any cause. All patients were monitored for survival analysis. A competing risk analysis was conducted to examine univariately a number of potential risk factors associated with hardware failure, including junctional level, gender, construct length, and the presence or absence of prior chest wall resection.

METHODS

A retrospective analysis and chart review were performed for 318 consecutive patients who underwent posterolateral decompression and posterior screw-rod fixation without supplemental anterior fixation from March 2004 to June 2011 at our institution. The median follow-up time for survivors without hardware failure was 399 days (range, 9-2,828), with a mean operative time of 3 hours. A total of 78% of patients died during the 7-year study period.

RESULTS

Of the 318 patients, nine (2.8%) exhibited signs and symptoms of hardware failure and required revision of the instrumentation. Patients with chest wall resection and those with initial construct length greater than six contiguous spinal levels exhibited a statistically significantly higher risk of symptomatic hardware failure than their counterparts. We observed a trend toward an increased risk of failure in women compared with men (p=.09).

CONCLUSIONS

The incidence of hardware failure is low in patients with MESCC who undergo posterolateral decompression and posterior screw-rod instrumentation. Moreover, the short operative time and low morbidity profile associated with this approach make it a reliable and acceptable method for the surgical treatment of MESCC. Patients with constructs spanning six or more levels or those with prior chest wall resection are at higher risk for instrumentation failure.

Kinetic simulations of the self-focusing and dissipation of finite-width electron plasma waves

Two-dimensional simulations, both Vlasov and particle-in-cell, are presented that show the evolution of the field and electron distribution of finite-width, nonlinear electron plasma waves. The intrinsically intertwined effects of self-focusing and dissipation of field energy caused by electron trapping are studied in simulated systems that are hundreds of wavelengths long in the transverse direction but only one wavelength long and periodic in the propagation direction. From various initial wave states, both the width at focus Δm relative to the initial width Δ0 and the maximum field amplitude at focus are shown to be a function of the growth rate of the transverse modulational instability γTPMI divided by the loss rate of field energy νE to electrons escaping the trapping region. With dissipation included, an amplitude threshold for self-focusing γTPMI/νE∼1 is found that supports the analysis of Rose [Phys. Plasmas 12, 012318 (2005)].

Kinetic theory and Vlasov simulation of nonlinear ion-acoustic waves in multi-ion species plasmas

The theory of damping and nonlinear frequency shifts from particles resonant with ion-acoustic waves (IAWs) is presented for multi-ion species plasma and compared to driven wave Vlasov simulations. Two distinct IAW modes may be supported in multi-ion species plasmas, broadly classified as fast and slow by their phase velocity relative to the constituent ion thermal velocities. In current fusion-relevant long pulse experiments, the ion to electron temperature ratio, T(i)/T(e), is expected to reach a level such that the least damped and thus more readily driven mode is the slow mode, with both linear and nonlinear properties that are shown to differ significantly from the fast mode. The lighter ion species of the slow mode is found to make no significant contribution to the IAW frequency shift despite typically being the dominant contributor to the Landau damping.

Local disease control for spinal metastases following "separation surgery" and adjuvant hypofractionated or high-dose single-fraction stereotactic radiosurgery: outcome analysis in 186 patients

OBJECT

Decompression surgery followed by adjuvant radiotherapy is an effective therapy for preservation or recovery of neurological function and achieving durable local disease control in patients suffering from metastatic epidural spinal cord compression (ESCC). The authors examine the outcomes of postoperative image-guided intensity-modulated radiation therapy delivered as single-fraction or hypofractionated stereotactic radiosurgery (SRS) for achieving long-term local tumor control.

METHODS

A retrospective chart review identified 186 patients with ESCC from spinal metastases who were treated with surgical decompression, instrumentation, and postoperative radiation delivered as either single-fraction SRS (24 Gy) in 40 patients (21.5%), high-dose hypofractionated SRS (24-30 Gy in 3 fractions) in 37 patients (19.9%), or low-dose hypofractionated SRS (18-36 Gy in 5 or 6 fractions) in 109 patients (58.6%). The relationships between postoperative adjuvant SRS dosing and fractionation, patient characteristics, tumor histology-specific radiosensitivity, grade of ESCC, extent of surgical decompression, response to preoperative radiotherapy, and local tumor control were evaluated by competing risks analysis.

RESULTS

The total cumulative incidence of local progression was 16.4% 1 year after SRS. Multivariate Gray competing risks analysis revealed a significant improvement in local control with high-dose hypofractionated SRS (4.1% cumulative incidence of local progression at 1 year, HR 0.12, p = 0.04) as compared with low-dose hypofractionated SRS (22.6% local progression at 1 year, HR 1). Although univariate analysis demonstrated a trend toward greater risk of local progression for patients in whom preoperative conventional external beam radiation therapy failed (22.2% local progression at 1 year, HR 1.96, p = 0.07) compared with patients who did not receive any preoperative radiotherapy (11.2% local progression at 1 year, HR 1), this association was not confirmed with multivariate analysis. No other variable significantly correlated with progression-free survival, including radiation sensitivity of tumor histology, grade of ESCC, extent of surgical decompression, or patient sex.

CONCLUSIONS

Postoperative adjuvant SRS following epidural spinal cord decompression and instrumentation is a safe and effective strategy for establishing durable local tumor control regardless of tumor histology-specific radiosensitivity. Patients who received high-dose hypofractionated SRS demonstrated 1-year local progression rates of less than 5% (95% CI 0%-12.2%), which were superior to the results of low-dose hypofractionated SRS. The local progression rate after single-fraction SRS was less than 10% (95% CI 0%-19.0%).

Spray-dried porcine plasma and yeast derived protein meal influence the adaption to weaning of primiparous and multiparous sow progeny in different ways

Pigs from 154 litters (n = 1132, 19 ± 3 days of age, 4.9 ± 1.1 kg of bodyweight) were used in a 3 × 2 factorial design to evaluate two raw materials with nutraceutical properties being used in feeds, spray-dried porcine plasma (SDPP) and a yeast protein meal, and their effects on growth performance, immune parameters and gastrointestinal adaption of piglets to weaning. Factors included dietary treatments being (1) 5% SDPP (PLA), (2) 3.5% yeast protein meal (NUP) and (3) medicated control (TMC) and parity (primiparous versus multiparous). The treatment groups were imposed from Day 19 through to weaning at Day 27. Selected pigs (n = 720, 28 ± 3 days of age, 7.4 ± 1.0 kg of bodyweight) were weaned and remained on their respective diets from Day 28 to Day 34. From Day 35 to Day 48 all group-housed pigs were offered a commercial weaner 1 diet, and from Day 49 to Day 68 pigs were offered a commercial weaner 2 diet. Growth performance, survival, and serum immunoglobulin G were monitored throughout the nursery phase (Day 28 to Day 68). Adaptation of the gastrointestinal tract in the acute post-weaning phase (Day 28 to Day 34) was assessed in 36 individually housed male weaners, with the effects of feed on structural, digestive, microbial and immune parameters along the gastrointestinal tract determined at Day 34. Pre-weaning feed disappearance was greater (P < 0.01) in multiparous litters independent of diet. In the commercial nursery, total removals (mortality and morbidity) were highest (P < 0.01) in primiparous sow progeny, with pigs offered NUP having greater (P ≤ 0.05) total removals. Pigs offered PLA had superior average daily gain, average daily feed intake and feed conversion ratio from Day 28 to Day 34 (P < 0.05). Pigs offered NUP tended to (P = 0.07) have superior average daily gain from Day 35 to Day 49. Pigs offered NUP had higher (P < 0.05) serum immunoglobulin G concentrations at Day 68 compared with pigs offered TMC, with the effect most pronounced in primiparous sow progeny. Individually housed weaners offered PLA consumed more (P < 0.05) feed on Day 30 to Day 31, had shorter relative intestine length (P < 0.05), greater villous height in the medial jejunum (P < 0.10) and lower immuno-pathology scores along the intestine. Pigs offered PLA also tended (P < 0.10) to have increased pancreatic-specific lipase and amylase activity compared with pigs offered NUP. Pigs offered NUP had a higher ratio of E. coli : coliforms in the colon (P < 0.01) and more counts of β-haemolytic bacteria in the medial jejunum (P < 0.05) and colon (P < 0.10). Diets containing either SDPP or NUP offered pigs benefits beyond nutrition relative to the medicated control diet. The benefits of SDPP were highly effective but transient, while the yeast derived protein had a successive or accumulative effect which was more pronounced in primiparous sow progeny.

Sex peptide of Drosophila melanogaster males is a global regulator of reproductive processes in females

Seminal fluid proteins (Sfps) alter female behaviour and physiology and can mediate sexual conflict. In Drosophila melanogaster, a single Sfp, the sex peptide (SP), triggers remarkable post-mating responses in females, including altered fecundity, feeding, immunity and sexual receptivity. These effects can favour the evolutionary interests of males while generating costs in females. We tested the hypothesis that SP is an upstream master-regulator able to induce diverse phenotypes through efficient induction of widespread transcriptional changes in females. We profiled mRNA responses to SP in adult female abdomen (Abd) and head+thorax (HT) tissues using microarrays at 3 and 6 h following mating. SP elicited a rich, subtle signature of temporally and spatially controlled mRNAs. There were significant alterations to genes linked to egg development, early embryogenesis, immunity, nutrient sensing, behaviour and, unexpectedly, phototransduction. There was substantially more variation in the direction of differential expression across time points in the HT versus Abd. The results support the idea that SP is an important regulator of gene expression in females. The expression of many genes in one sex can therefore be under the influence of a regulator expressed in the other. This could influence the extent of sexual conflict both within and between loci.

Variation in adult sex ratio alters the association between courtship, mating frequency and paternity in the lek-forming fruitfly Ceratitis capitata

The intensity with which males deliver courtship and the frequency with which they mate are key components of male reproductive success. However, we expect the strength of the relationship between these traits and a male's overall paternity to be strongly context dependent, for example to be altered significantly by the extent of post-mating competition. We tested this prediction in a lekking insect, Ceratitis capitata (medfly). We examined the effect of manipulating the sex ratio from male- to female-biased (high and low male competition, respectively) on courtship behaviour, mating frequency and paternity of focal males. Under high male competition, focal males delivered significantly more courtship but gained lower paternity than under lower competition. Paternity was positively associated with mating frequency and small residual testes size. However, the association between mating frequency and paternity was significantly stronger under low competition. We conclude that manipulation of sex ratio significantly altered the predictors of mating success and paternity. The relationship between pre- and post-mating success is therefore plastic and alters according to the prevailing level of competition. The results highlight the importance of post-copulatory processes in lekking species and illuminate selection pressures placed on insects such as medflies that are mass reared for pest control.

Driven spatially autoresonant stimulated Raman scattering in the kinetic regime

The autoresonant behavior of Langmuir waves excited by stimulated Raman scattering (SRS) is clearly identified in particle-in-cell (PIC) simulations in an inhomogeneous plasma. As previously shown via a 3-wave coupling model [T. Chapman et al., Phys. Plasmas 17, 122317 (2010)], weakly kinetic effects such as trapping can be described via an amplitude-dependent frequency shift that compensates the dephasing of the resonance of SRS due to the inhomogeneity. The autoresonance (AR) leads to phase locking and to growth of the Langmuir wave beyond the spatial amplification expected from Rosenbluth's model in an inhomogeneous profile [M. N. Rosenbluth, Phys. Rev. Lett. 29, 565 (1972)]. Results from PIC simulations and from a 3-wave coupling code show very good agreement, leading to the conclusion that AR arises even beyond the so-called weakly kinetic regime.

Characterisation of amyloid-induced inflammatory responses in the rat retina

Amyloid-induced inflammation is thought to play a critical and early role in the pathophysiology of Alzheimer's disease. As such, robust models with relevant and accessible compartments that provide a means of assessing anti-inflammatory agents are essential for the development of therapeutic agents. In the present work, we have characterised the induction of inflammation in the rat retina following intravitreal administration of amyloid-beta protein (Aβ). Histology and mRNA endpoints in the retina demonstrate Aβ1-42-, but not Aβ42-1-, induced inflammatory responses characterised by increases in markers for microglia and astrocytes (ionised calcium-binding adaptor molecule 1 (iba-1), GFAP and nestin) and increases in mRNA for inflammatory cytokines and chemokines such as IL1-β, MIP1α and TNFα. Likewise, analysis of vitreal cytokines also revealed increases in inflammatory cytokines and chemokines, including IL1-β, MIP1α and MCP1, induced by Aβ1-42 but not Aβ42-1. This profile of pro-inflammatory gene and protein expression is consistent with that observed in the Alzheimer's disease brain and suggest that this preclinical model may provide a useful relevant tool in the development of anti-inflammatory approaches directed towards Alzheimer's disease therapy.

Female nutritional status determines the magnitude and sign of responses to a male ejaculate signal in Drosophila melanogaster

Ejaculate chemicals transferred from males to females during mating cause significant changes in female behaviour and physiology, but the causes of phenotypic variation in these responses is little understood. We tested here the effect of adult female nutrition on the response of female Drosophila melanogaster to a specific ejaculate component, the sex peptide (SP), which is of interest because of its effects on female egg laying, sexual receptivity, feeding rate, immune responses and potential role in mediating sexual conflict. We exposed adult females to five different diets and kept them continuously with males that did or did not transfer SP. Diet altered the presence, magnitude and sign of the effects of SP on different phenotypic traits (egg laying, receptivity and lifespan) and different traits responded in different ways. This showed that the set of responses to mating can be uncoupled and can vary independently in different environments. Importantly, diet also significantly affected whether exposure to SP transferring males was beneficial or costly to females, with beneficial effects occurring more often than expected. Hence, the food environment can also shape significantly the strength and direction of selection on mating responses.

Decreased muscle strength following management of breast cancer

PURPOSE

To assess whether muscle strength, power and endurance at the affected shoulder were reduced in women treated for breast cancer. Secondly, we assessed whether muscle performance was explained by management or other symptoms.

METHODS

Participants were 40 women (mean +/- SD: 56.7 +/- 11.6 yr) who had completed all treatments for breast cancer at least 6 m previously. We measured dynamic concentric strength at one repetition maximum (1RM), endurance at 90% 1RM, and power through a range of 40-100% 1RM for shoulder protractors, extensors and retractors. Strength and endurance, but not power, were measured for shoulder flexors. Additionally, maximal grip strength, passive shoulder range of motion and arm circumference were measured. Self-reported symptoms were recorded using a questionnaire.

RESULTS

Shoulder protractors (p = 0.011), retractors (p = 0.007), and extensors (p = 0.009), but not flexors, were significantly weaker on the affected side compared to the unaffected side. Muscle power and endurance at the shoulder and grip strength were not impaired. Inter-limb differences in muscle strength were not explained by the surgical and medical management of the cancer. Self-reported weakness correlated poorly with our measures of muscle strength.

CONCLUSIONS

Long-term weakness occurs about the shoulder secondary to treatment for breast cancer. Strategies to prevent weakness need to be considered.