A WC/WO star exploding within an expanding carbon-oxygen-neon nebula.

The final fate of massive stars, and the nature of the compact remnants they leave behind (black holes and neutron stars), are open questions in astrophysics. Many massive stars are stripped of their outer hydrogen envelopes as they evolve. Such Wolf-Rayet stars1 emit strong and rapidly expanding winds with speeds greater than 1,000 kilometres per second. A fraction of this population is also helium-depleted, with spectra dominated by highly ionized emission lines of carbon and oxygen (types WC/WO). Evidence indicates that the most commonly observed supernova explosions that lack hydrogen and helium (types Ib/Ic) cannot result from massive WC/WO stars2,3, leading some to suggest that most such stars collapse directly into black holes without a visible supernova explosion4. Here we report observations of SN 2019hgp, beginning about a day after the explosion. Its short rise time and rapid decline place it among an emerging population of rapidly evolving transients5-8. Spectroscopy reveals a rich set of emission lines indicating that the explosion occurred within a nebula composed of carbon, oxygen and neon. Narrow absorption features show that this material is expanding at high velocities (greater than 1,500 kilometres per second), requiring a compact progenitor. Our observations are consistent with an explosion of a massive WC/WO star, and suggest that massive Wolf-Rayet stars may be the progenitors of some rapidly evolving transients.

Genetic profile of Brazilian patients with dystrophinopathies.

Different types of mutations in the DMD gene underlie Duchenne muscular dystrophies (DMD) and Becker muscular dystrophies (BMD). Large deletions and duplications are the most frequent causative genetic alterations worldwide, but little is known about DMD/BMD genetic profile in Brazil. Hence, we recruited patients with DMD and BMD from 8 neuromuscular reference centers along the country, and performed a comprehensive molecular investigation that included Multiplex Ligation-dependent Probe Amplification and Next generation sequencing (NGS) analyses. We evaluated 199 patients from 177 unrelated families: 166 with DMD, 32 with BMD and 1 1.5 years old asymptomatic patient with persistent hiperCKemia. Overall, large deletions (58.2%) followed by nonsense mutations (12.4%) and large duplications (11.3%) were the most frequent variants in Brazilian families. Large deletions were less frequent in BMD than in DMD (44.8% vs 60.8%). We identified 19 new DMD variants. Nonsense mutations were significantly more frequent in patients from northeastern region than from southern/southeastern regions of Brazil (27.7% vs 8.5%, P < .05). Genetic profile of Brazilian patients with DMD/BMD is similar to previously reported cohorts, but it is not uniform across the country. This information is important to plan rational clinical care for patients in face of the new coming mutation-specific therapies.

Transcriptional and cellular effects of paracetamol in the oyster Crassostrea gigas.

Acetaminophen (paracetamol) (PAR) is one of the most popular non-steroidal anti-inflammatory drugs (NSAIDs) with analgesic and antipyretic properties consumed worldwide and often detected in the aquatic environment. Due to the fact that PAR induces oxidative stress in mammals, the aim of this study was to evaluate if similar effects were observed in oysters Crassostrea gigas, given their economic and ecological importance and worldwide distribution. Oysters were exposed for 1, 4 and 7 days to two different sublethal PAR concentrations (0, 1 and 100µgL-1). Cell viability, DNA damage in hemocytes and enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx), glutathione reductase (GR), glucose 6-phosphate dehydrogenase (G6PDH) and glutathione S-transferases (GST) were evaluated in oyster gills. In addition, changes at transcriptional level of Cu/Zn superoxide dismutase (SOD), catalase-like (CAT-like), cytochrome P450 genes (CYP30C1, CYP2AU2, CYP3071A1, CYP356A1), glutathione S-transferase isoforms (GST-ω and GST-π-like), cyclooxygenase (COX), fatty acid binding proteins-like (FABP-like), and caspase genes were evaluated in oyster gills and digestive gland. No changes in cell viability and DNA damage were observed in oysters exposed to both PAR concentrations. Similarly, no significant changes were detected in the major antioxidant enzymes (except for auxiliary enzyme GR) in oyster gills, suggesting that changes in GR activity are enough to counteract a potential oxidative stress in C. gigas gills under these experimental conditions. Furthermore, changes at transcriptional level are concentration and tissue dependent. PAR elicited an inhibition of CYP30C1, CYP3071A1 and FABP-like transcripts highlighting their role in drug metabolism, transport and detoxification of PAR in the gills. GST transcript levels were type, tissue and concentration-dependent. GST-π-like was down-regulated in oyster gills exposed to the lowest PAR concentration and up-regulated in the digestive gland of oysters exposed to the highest PAR concentration. However, GST-ω transcript levels were lower only in oysters digestive gland exposed to the lowest PAR concentration. Therefore, changes at transcriptional level were more sensitive to assess the exposure to PAR at environmental relevant concentrations.

Assessment of anti-Müllerian hormone levels in premenopausal patients with systemic lupus erythematosus.

OBJECTIVE: The ovarian reserve of patients with systemic lupus erythematosus (SLE) may be affected by disease activity and medication use. Studies have found that patients with SLE have similar fertility rates as healthy women of the same age. The goal of the present study was to investigate the ovarian reserve of patients with SLE by measuring anti-Müllerian hormone (AMH) levels, and compare it to that of healthy controls. METHOD: This was a case-control study performed on 80 premenopausal women, of whom 40 fulfilled the 1997 American College of Rheumatology (ACR) criteria for SLE and 40 healthy controls paired by oral contraceptive use. Serum concentrations of AMH in peripheral venous blood were measured using a human AMH ELISA kit (CUSABIO, Wuhan, China). RESULTS: AMH serum levels did not differ between patients with SLE and controls (22.79 ± 17.32 ng/ml versus 21.41 ± 16.22 ng/ml, respectively, p = 0.7), even after adjusting for age (21.03 ± 2.074 ng/ml versus 23.97 ± 2.71 ng/ml; p = 0.5). AHM levels were not significantly correlated with disease duration (r = 0.2; p = 0.3), body mass index (r = 0.2; p = 0.2) and disease activity (SLEDAI (r = 0.1; p = 0.7)) and damage indices (SLICC (r = 0.1; p = 0.7)). No associations were found between AMH and ethnicity, current smoking, as well as current or prior use of cyclophosphamide and other immunosuppressants. CONCLUSION: In this cross-sectional study, women with SLE demonstrated similar AMH levels as healthy controls, suggesting preserved ovarian reserve in this population.

Efficacy of pyramided Bt proteins Cry1F, Cry1A.105, and cry2Ab2 expressed in Smartstax corn hybrids against lepidopteran insect pests in the northern United States.

Commercial field corn (Zea mays L.) hybrids transformed to express some or all of the lepidopteran insect-resistant traits present in SmartStax corn hybrids were evaluated for insecticidal efficacy against a wide range oflepidopteran corn pests common to the northern United States, during 2008 to 2011 at locations in 15 states. SmartStax hybrids contain a pyramid of two Bacillus thuringiensis (Bt) derived events for lepidopteran control: event TC1507 expressing Cry1F protein and MON 89034 expressing CrylA.105 + Cry2Ab2. These studies focused on characterization of the relative efficacy of each event when expressed alone or in combination, and compared with non-Bt hybrid. Corn hybrids containing pyramided insecticidal proteins Cry1F + Cry1A.105 + Cry2Ab2 (SmartStax) consistently showed reduced plant feeding damage by a wide range of lepidopteran larvae compared with single event and non-Bt hybrids. Corn hybrids expressing TC1507 or MON 89034 as single or pyramided events were consistently efficacious against Ostrinia nubilalis (Hübner). SmartStax hybrids had less injury from Agrotis ipsilon (Hufnagel) and Striacosta albicosta (Smith) than corn hybrids containing only event MON 89034 but were not more efficacious than single event TC1507 hybrids. Corn hybrids with event MON 89034 provided better control of Helicoverpa zea (Boddie), than event TC1507 alone. Spodoptera frugiperda (J.E. Smith) efficacy was higher for hybrids with pyramid events and single events compared with the non-Bt hybrids. The spectra of activity of events TC1507 and MON 89034 differed. The combination of TC1507 + MON 89034 provided redundant control of some pests where the spectra overlapped and thereby are expected to confer a resistance management benefit.

Microbiological epidemiology and antibiotic susceptibility of infected meshes after prosthetic abdominal wall repair.

INTRODUCTION: Infectious complications of parietal mesh after prosthetic abdominal wall repair are rare. Their management is complex. Furthermore, the emergence of bacterial resistance, the presence of a foreign material, the need to continue an extended antibiotic therapy, and the choice of an appropriate treatment are crucial. The objective of this study is to access the microbiological epidemiology of infected parietal meshes in order to optimize the empirical antibiotic therapy. METHODS: Between January 2016 and December 2021, a monocentric and retrospective study was performed in patients hospitalized for infected parietal meshes at Avicenne hospital, in Paris area. Clinical and microbiological data such as antibiotic susceptibility were collected. RESULTS: Twenty-six patients with infected parietal meshes have been hospitalized during this period. Meshes were in preaponevrotic positions (n=10; 38%), retromuscular (n=6; 23%) and intraperitoneal (n=10; 38%). Among the 22 (84.6%) documented cases of infections, 17 (77.3%) were polymicrobial. A total of 54 bacteria were isolated, 48 of which had an antibiogram available. The most frequently isolated bacteria were: Enterobacterales (n=19), Enterococcus spp. (n=11) and Staphylococcus aureus (n=6), whereas anaerobes were poorly isolated (n=3). Concerning these isolated bacteria, amoxicillin-clavulanic acid, metronidazole-associated cefotaxime, piperacillin-tazobactam and meropenem were susceptible in 45.5%, 68.2%, 63.6%, 77.2%, of cases, respectively. CONCLUSION: This work highlights that infections of abdominal parietal meshes may be polymicrobial and the association amoxicillin-clavulanic acid cannot be used as a probabilist antibiotic therapy because of the high resistance rate in isolated bacteria. The association piperacillin-tazobactam appears to be a more adapted empirical treatment to preserve carbapenems, a broad-spectrum antibiotic class.

Evaluation of corn hybrids expressing Cry1F, cry1A.105, Cry2Ab2, Cry34Ab1/Cry35Ab1, and Cry3Bb1 against southern United States insect pests.

Studies were conducted across the southern United States to characterize the efficacy of multiple Bacillus thuringiensis (Bt) events in a field corn, Zea mays L., hybrid for control of common lepidopteran and coleopteran pests. Cry1F protein in event TC1507 and Cry1A.105 + Cry2Ab2 proteins in event MON 89034 were evaluated against pests infesting corn on above-ground plant tissue including foliage, stalks, and ears. Cry34Ab1/Cry35Ab1 proteins in event DAS-59122-7 and Cry3Bb1 in event MON 88017 were evaluated against the larvae of Mexican corn rootworm, Diabrotica virgifera zeae Krysan and Smith, which occur below-ground. Field corn hybrids containing Cry1F, Cry1A.105 + Cry2Ab2, Cry34Ab1/Cry35Ab1, and Cry3Bb1 insecticidal proteins (SmartStax) consistently demonstrated reductions in plant injury and/or reduced larval survivorship as compared with a non-Bt field corn hybrid. Efficacy provided by a field corn hybrid with multiple Bt proteins was statistically equal to or significantly better than corn hybrids containing a single event active against target pests. Single event field corn hybrids provided very high levels of control of southwestern corn borer, Diatraea grandiosella (Dyar), lesser cornstalk borer, Elasmopalpus lignosellus (Zeller), and fall armyworm, Spodoptera frugiperda (J.E. Smith), and were not significantly different than field corn hybrids with multiple events. Significant increases in efficacy were observed for a field corn hybrid with multiple Bt events for sugarcane borer, Diatraea saccharalis (F.), beet armyworm, Spodoptera exigua (Hübner), corn earworm, Helicoverpa zea (Boddie), and Mexican corn rootworm. Utilization of field corn hybrids containing multiple Bt events provides a means for managing insect resistance to Bt proteins and reduces non-Bt corn refuge requirements.

Management of gastro-intestinal emergencies in patients with ileal conduit ureteral diversion.

Radical cystectomy with urinary deviation is performed increasingly in France. Ileal conduit ureteral diversion (ICUD), described by Bricker and widely used after this type of radical resection, leads to substantial anatomic modifications that are potential danger zones during subsequent gastro-intestinal or urinary tract operations. Injury to the urinary diversion apparatus can lead to disastrous complications in these patients who are often elderly and frail. General surgeons are most often called upon to re-operate these patients, either for an ICUD-related gastro-intestinal complication, or for an unrelated abdominal emergency that arises later (bowel obstruction, infection, cancer). During such operations, certain anatomic structures are particularly exposed to injury that may be irreversible, particularly, the mesentery of the ileal conduit and the left ureter. Approaching the right lower quadrant, the dissection of the ileo-ileal anastomosis or of the left mesocolon are the procedures or maneuvers that pose the most risk. A number of simple but effective preventive measures are available and must be known, such as to operate the patient with an urologist or to insert ureteral stents before surgery. Preoperative contrast-enhanced computed tomography with late phase urinary imaging is essential to assess the anatomic modifications and anticipate the operative procedural steps. Finally, one should not hesitate to disinsert the stoma and proceed with retrograde dissection, thus facilitating the identification of the ileal conduit, the mesentery and the ureters.

Management of abdominal compartment syndrome in acute pancreatitis.

Abdominal compartment syndrome (ACS), defined by the presence of increased intra-abdominal pressure>20mmHg in association with failure of at least one organ system, is a common and feared complication that may occur in the early phase of severe acute pancreatitis (AP). This complication can lead to patient death in the very short term. The goal of this review is to provide the surgeon and intensivist with objective information to help them in their decision-making. In the early phase of severe AP, it is essential to monitor intra-vesical pressure (iVP) to allow early diagnosis of intra-abdominal hypertension or ACS. The treatment of ACS is both medical and surgical requiring close collaboration between the surgical and resuscitation teams. Medical treatment includes vascular volume repletion, prokinetic agents, effective curarization and percutaneous drainage of large-volume ascites. If uncontrolled respiratory or cardiac failure develops or if maximum medical treatment fails, most teams favor performing an emergency xipho-pubic decompression laparotomy with laparostomy. This procedure follows the principles of abbreviated laparotomy as described for abdominal trauma.

Local structure of uncapped and capped InGaN/GaN quantum dots.

The local structure around the indium atoms in uncapped and capped In(x)Ga(1-x)N quantum dots has been studied by In K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy. The samples were grown by metal organic vapour phase epitaxy. The EXAFS was successfully applied to study the structural properties of buried quantum dots which are not optically active. The analysis revealed that capping the quantum dots with GaN does not affect the bond distances of the In-N and In-Ga, but makes the In-In distance shorter by 0.04 A.

Identification of novel graded polarity actin filament bundles in locomoting heart fibroblasts: implications for the generation of motile force.

We have determined the structural organization and dynamic behavior of actin filaments in entire primary locomoting heart fibroblasts by S1 decoration, serial section EM, and photoactivation of fluorescence. As expected, actin filaments in the lamellipodium of these cells have uniform polarity with barbed ends facing forward. In the lamella, cell body, and tail there are two observable types of actin filament organization. A less abundant type is located on the inner surface of the plasma membrane and is composed of short, overlapping actin bundles (0.25-2.5 microm) that repeatedly alternate in polarity from uniform barbed ends forward to uniform pointed ends forward. This type of organization is similar to the organization we show for actin filament bundles (stress fibers) in nonlocomoting cells (PtK2 cells) and to the known organization of muscle sarcomeres. The more abundant type of actin filament organization in locomoting heart fibroblasts is mostly ventrally located and is composed of long, overlapping bundles (average 13 microm, but can reach up to about 30 microm) which span the length of the cell. This more abundant type has a novel graded polarity organization. In each actin bundle, polarity gradually changes along the length of the bundle. Actual actin filament polarity at any given point in the bundle is determined by position in the cell; the closer to the front of the cell the more barbed ends of actin filaments face forward. By photoactivation marking in locomoting heart fibroblasts, as expected in the lamellipodium, actin filaments flow rearward with respect to substrate. In the lamella, all marked and observed actin filaments remain stationary with respect to substrate as the fibroblast locomotes. In the cell body of locomoting fibroblasts there are two dynamic populations of actin filaments: one remains stationary and the other moves forward with respect to substrate at the rate of the cell body. This is the first time that the structural organization and dynamics of actin filaments have been determined in an entire locomoting cell. The organization, dynamics, and relative abundance of graded polarity actin filament bundles have important implications for the generation of motile force during primary heart fibroblast locomotion.

Efficacy of Cry1Ac:Cry1F proteins in cotton leaf tissue against fall armyworm, beet armyworm, and soybean looper (Lepidoptera: Noctuidae).

Cotton, Gossypium hirsutum L., plants expressing Cry1Ac and Cry1F insecticidal crystal proteins of Bacillus thuringiensis Berliner (Bt) were evaluated against selected lepidopteran pests including fall armyworm, Spodoptera frugiperda (J. E. Smith), beet armyworm, Spodoptera exigua (Hübner), and soybean looper, Pseudoplusia includens (Walker). Studies were conducted in a range of environments, challenging various cotton tissue types from several varieties containing a combination of Cry1Ac and Cry1F proteins. In fresh tissue bioassays of mature leaves and squares (flower buds) and in artificial field infestations of white flowers, plants containing Cry1Ac:Cry1F significantly reduced levels of damage (leaf defoliation, bract feeding, penetrated squares and bolls, and boll abscission) and induced significantly greater mortality (90-100%) of fall armyworm compared with that on non-Bt cotton plants. Plants containing Cry1Ac:Cry1F conferred high levels (100%) of soybean looper mortality and low levels (0.2%) of leaf defoliation compared with non-Bt cotton. Beet armyworm was relatively less sensitive to Cry1Ac:Cry1F cotton plants compared with fall armyworm and soybean looper. However, beet armyworm larval development was delayed 21 d after infestation (DAI), and ingestion of plant tissue was inhibited (14 and 21 DAI) on the Cry1Ac:Cry1F plants compared with that on non-Bt cotton plants. These results show Cry1Ac:Cry1F cotton varieties can be an effective component in a management program for these lepidopteran pest species. Differential susceptibility of fall armyworm, beet armyworm, and soybean looper larvae to Cry1Ac:Cry1F cotton reinforces the need to sample during plant development and respond with a foliar insecticide if local action thresholds are exceeded.

Quantification of Cry1Ac and Cry1F Bacillus thuringiensis insecticidal proteins in selected transgenic cotton plant tissue types.

Quantitative enzyme-linked immunosorbent assays were used to characterize the geographical (locations) and temporal (through 6 wk) expression of CrylAc, from Bacillus thuringiensis variety kurstaki, and Cry1F, from B. thuringiensis variety aizawai, in transgenic cotton, Gossypium hirsutum L., plant structures. Terminal leaves, squares (flower buds), flowers, bolls (fruit), and mature leaves located five and eight nodes below the terminal apex were sampled during weeks 2, 4, and 6 after the initiation of anthesis. The effect of location (environment) significantly influenced protein expression levels, although similar trends were observed across locations. Cry1F was expressed at levels greater (1.1-29.0-fold) than that for CrylAc in all structures with exception to flowers. In contrast, the level of CrylAc in flowers was generally greater than Cry1F. Within each sampling period, concentrations of Cry1F in mature leaves (five and eight node) were greater than that for other structures. Expression was also greater for older, eight-node mature leaves than younger, five-node mature leaves. CrylAc expression in bolls was lowest compared with terminal leaves, squares, flowers, and mature leaves, which expressed at similar concentrations. Cry1F expression increased through time for mature leaves and terminal leaves; whereas, a decline in Cry1Ac protein concentration was observed for terminal leaves and bolls. The data presented here provides a means to understand observed levels of efficacy (patterns of insect damage) by comparing the spatial and temporal dynamics of expression for Cry1Ac and Cry1F in PhytoGen 440W transgenic cotton.

Interaction between C-Tb and PPD given concomitantly in a split-body randomised controlled trial.

SETTING: Seven tuberculosis (TB) clinics in South Africa. OBJECTIVE: As both purified protein derivative (PPD) and a Mycobacterium tuberculosis-specific skin test (C-Tb) contain region of difference 1 (RD1) antigens, we conducted a study to evaluate whether there was any interaction between the two during concomitant and separate administration in patients with newly diagnosed culture-positive TB. DESIGN: Adult patients with active TB (n = 456, 20% human immunodeficiency virus infected) were randomised to receive only C-Tb, only PPD, or concomitant injection of both C-Tb and PPD using the Mantoux technique. Indurations were read after 48-72 h. QuantiFERON®-TB Gold In-Tube (QFT) was performed in tandem. RESULTS: Of the 456 study participants, 154 simultaneously received both C-Tb and PPD, 153 only C-Tb and 149 only PPD. There was no effect of concomitant injection of PPD on the mean C-Tb induration (19 mm, 95%CI 17-22 vs. 18 mm, 95%CI 16-21; P = 0.91). In patients with active TB, C-Tb sensitivity (78%) was similar to PPD (81%) and QFT (84%; excluding 82/429 [19%] indeterminate results). All tests showed reduced sensitivity in participants with CD4 <100 cells/µl. CONCLUSION: In patients with active TB, there was no interaction between C-Tb and PPD during concomitant injection of both agents. Sensitivities were similar for PPD and C-Tb.

Efficacy of transgenic cotton expressing Cry1Ac and Cry1F insecticidal protein against heliothines (Lepidoptera: Noctuidae).

Cotton, Cossypium hirsutum L, plants expressing Cry1Ac and Cry1F (Phytogen 440W) insecticidal crystal proteins of Bacillus thuringiensis (Bt) Berliner, were evaluated against natural populations of tobacco budworm, Heliothis virescens (F.), and bollworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), across 13 southern U.S. locations that sustained low, moderate, and high infestations. The intrinsic activity of Phytogen 440W was compared with nontreated non-Bt cotton (PSC355) and with management strategies in which supplemental insecticides targeting heliothines were applied to Phytogen 440W and to PSC355 cotton. Infestations were composed primarily of bollworm, which is the least sensitive of the heliothine complex to Cry toxins. Therefore, damage recorded in these studies was primarily due to bollworm. Greater than 75% of all test sites sustained heliothine infestations categorized as moderate to high (10.6-64.0% peak damaged bolls in nontreated PSC355). Phytogen 440W, alone or managed with supplemental insecticide applications, reduced heliothine-damaged plant terminals, squares (flower buds), flowers, and bolls equal to or better (1.0-79.0-fold) than managing a non-Bt cotton variety with foliar insecticides across all infestation environments. Rarely (frequency of < or = 11% averaged across structures), sprayed Phytogen 440W reduced damaged structures compared with nontreated Phytogen 440W. Protection against heliothine-induced plant damage was similar across the three levels of infestation for each viable management strategy, with exception to damaged squares for nontreated Phytogen 440W. In situations of moderate to high heliothine infestations, cotton plants expressing Cry1Ac and Cry1F may sustain higher levels of damage compared with that same variety in low infestations. No significant difference in yield was observed among heliothine management strategies within each infestation level, indicating cotton plants may compensate for those levels of plant damage. These findings indicate Phytogen 440W containing Cry1Ac and Cry1F provided consistent control of heliothines across a range of environments and infestation levels.

Swope Supernova Survey 2017a (SSS17a), the optical counterpart to a gravitational wave source.

On 17 August 2017, the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo interferometer detected gravitational waves (GWs) emanating from a binary neutron star merger, GW170817. Nearly simultaneously, the Fermi and INTEGRAL (INTErnational Gamma-Ray Astrophysics Laboratory) telescopes detected a gamma-ray transient, GRB 170817A. At 10.9 hours after the GW trigger, we discovered a transient and fading optical source, Swope Supernova Survey 2017a (SSS17a), coincident with GW170817. SSS17a is located in NGC 4993, an S0 galaxy at a distance of 40 megaparsecs. The precise location of GW170817 provides an opportunity to probe the nature of these cataclysmic events by combining electromagnetic and GW observations.

Electromagnetic evidence that SSS17a is the result of a binary neutron star merger.

Eleven hours after the detection of gravitational wave source GW170817 by the Laser Interferometer Gravitational-Wave Observatory and Virgo Interferometers, an associated optical transient, SSS17a, was identified in the galaxy NGC 4993. Although the gravitational wave data indicate that GW170817 is consistent with the merger of two compact objects, the electromagnetic observations provide independent constraints on the nature of that system. We synthesize the optical to near-infrared photometry and spectroscopy of SSS17a collected by the One-Meter Two-Hemisphere collaboration, finding that SSS17a is unlike other known transients. The source is best described by theoretical models of a kilonova consisting of radioactive elements produced by rapid neutron capture (the r-process). We conclude that SSS17a was the result of a binary neutron star merger, reinforcing the gravitational wave result.

Early spectra of the gravitational wave source GW170817: Evolution of a neutron star merger.

On 17 August 2017, Swope Supernova Survey 2017a (SSS17a) was discovered as the optical counterpart of the binary neutron star gravitational wave event GW170817. We report time-series spectroscopy of SSS17a from 11.75 hours until 8.5 days after the merger. Over the first hour of observations, the ejecta rapidly expanded and cooled. Applying blackbody fits to the spectra, we measured the photosphere cooling from [Formula: see text] to [Formula: see text] kelvin, and determined a photospheric velocity of roughly 30% of the speed of light. The spectra of SSS17a began displaying broad features after 1.46 days and evolved qualitatively over each subsequent day, with distinct blue (early-time) and red (late-time) components. The late-time component is consistent with theoretical models of r-process-enriched neutron star ejecta, whereas the blue component requires high-velocity, lanthanide-free material.

Light curves of the neutron star merger GW170817/SSS17a: Implications for r-process nucleosynthesis.

On 17 August 2017, gravitational waves (GWs) were detected from a binary neutron star merger, GW170817, along with a coincident short gamma-ray burst, GRB 170817A. An optical transient source, Swope Supernova Survey 17a (SSS17a), was subsequently identified as the counterpart of this event. We present ultraviolet, optical, and infrared light curves of SSS17a extending from 10.9 hours to 18 days postmerger. We constrain the radioactively powered transient resulting from the ejection of neutron-rich material. The fast rise of the light curves, subsequent decay, and rapid color evolution are consistent with multiple ejecta components of differing lanthanide abundance. The late-time light curve indicates that SSS17a produced at least ~0.05 solar masses of heavy elements, demonstrating that neutron star mergers play a role in rapid neutron capture (r-process) nucleosynthesis in the universe.

Management of splenic and pancreatic trauma.

The spleen and pancreas are at risk for injury during abdominal trauma. The spleen is more commonly injured because of its fragile structure and its position immediately beneath the ribs. Injury to the more deeply placed pancreas is classically characterized by discordance between the severity of pancreatic injury and its initial clinical expression. For the patient who presents with hemorrhagic shock and ultrasound evidence of major hemoperitoneum, urgent "damage control" laparotomy is essential; if splenic injury is the cause, prompt "hemostatic" splenectomy should be performed. Direct pancreatic injury is rarely the cause of major hemorrhage unless a major neighboring vessel is injured, but if there is destruction of the pancreatic head, a two-stage pancreatoduodenectomy (PD) may be indicated. At open laparotomy when the patient's hemodynamic status can be stabilized, it may be possible to control splenic bleeding without splenectomy; it is always essential to search for injury to the pancreatic duct and/or the adjacent duodenum. Pancreatic contusion without ductal rupture is usually treated by drain placement adjacent to the injury; ductal injuries of the pancreatic body or tail are treated by resection (distal pancreatectomy with or without splenectomy), with generally benign consequences. For injuries of the pancreatic head with pancreatic duct disruption, wide drainage is usually performed because emergency PD is a complex gesture prone to poor results. Postoperatively, the placement of a ductal stent by endoscopic retrograde catheterization may be decided, while management of an isolated pancreatic fistula is often straightforward. Non-operative management is the rule for the trauma victim who is hemodynamically stable. In addition to the clinical examination and conventional laboratory tests, investigations should include an abdominothoracic CT scan with contrast injection, allowing identification of all traumatized organs and assessment of the severity of injury. In this context, non-operative management (NOM) has gradually become the standard as long as the patient remains hemodynamically stable and there is no suspicion of injury to hollow viscera, with the patient being carefully monitored on a surgical service. The development of arteriography with splenic artery embolization has increased the rate of splenic salvage; this can be performed electively based on specific indications (blush on CT, pseudoaneurysm, arteriovenous fistula), and may also be considered for severe splenic injury, abundant hemoperitoneum, or severe polytrauma. For pancreatic injury, in addition to CT scan, magnetic resonance pancreatography (MRCP) or even endoscopic retrograde cholangiopancreatography (ERCP) may be necessary to identify a ductal rupture. If the pancreatic duct is intact, laboratory and CT imaging surveillance is performed just as for splenic injury. In case of pancreatic ductal injury, ERCP stenting can be considered. However, if this is unsuccessful, the therapeutic decision can be difficult: while NOM can still be successful, complications may arise that are difficult to treat while distal pancreatectomy, although initially more agressive may avoid these complications if performed early.