A dust-obscured massive maximum-starburst galaxy at a redshift of 6.34.

Massive present-day early-type (elliptical and lenticular) galaxies probably gained the bulk of their stellar mass and heavy elements through intense, dust-enshrouded starbursts--that is, increased rates of star formation--in the most massive dark-matter haloes at early epochs. However, it remains unknown how soon after the Big Bang massive starburst progenitors exist. The measured redshift (z) distribution of dusty, massive starbursts has long been suspected to be biased low in z owing to selection effects, as confirmed by recent findings of systems with redshifts as high as ~5 (refs 2-4). Here we report the identification of a massive starburst galaxy at z = 6.34 through a submillimetre colour-selection technique. We unambiguously determined the redshift from a suite of molecular and atomic fine-structure cooling lines. These measurements reveal a hundred billion solar masses of highly excited, chemically evolved interstellar medium in this galaxy, which constitutes at least 40 per cent of the baryonic mass. A 'maximum starburst' converts the gas into stars at a rate more than 2,000 times that of the Milky Way, a rate among the highest observed at any epoch. Despite the overall downturn in cosmic star formation towards the highest redshifts, it seems that environments mature enough to form the most massive, intense starbursts existed at least as early as 880 million years after the Big Bang.

Bright Soliton to Quantum Droplet Transition in a Mixture of Bose-Einstein Condensates.

Attractive Bose-Einstein condensates can host two types of macroscopic self-bound states: bright solitons and quantum droplets. Here, we investigate the connection between them with a Bose-Bose mixture confined in an optical waveguide. We show theoretically that, depending on atom number and interaction strength, solitons and droplets can be smoothly connected or remain distinct states coexisting only in a bistable region. We measure their spin composition, extract their density for a broad range of parameters, and map out the boundary of the region separating solitons from droplets.

Competition between Bose-Einstein Condensation and Spin Dynamics.

We study the impact of spin-exchange collisions on the dynamics of Bose-Einstein condensation by rapidly cooling a chromium multicomponent Bose gas. Despite relatively strong spin-dependent interactions, the critical temperature for Bose-Einstein condensation is reached before the spin degrees of freedom fully thermalize. The increase in density due to Bose-Einstein condensation then triggers spin dynamics, hampering the formation of condensates in spin-excited states. Small metastable spinor condensates are, nevertheless, produced, and they manifest in strong spin fluctuations.

Cooling of a Bose-Einstein Condensate by Spin Distillation.

We propose and experimentally demonstrate a new cooling mechanism leading to purification of a Bose-Einstein condensate (BEC). Our scheme starts with a BEC polarized in the lowest energy spin state. Spin excited states are thermally populated by lowering the single particle energy gap set by the magnetic field. Then, these spin-excited thermal components are filtered out, which leads to an increase of the BEC fraction. We experimentally demonstrate such cooling for a spin 3 ^{52}Cr dipolar BEC. Our scheme should be applicable to Na or Rb, with the perspective to reach temperatures below 1 nK.

The formation of ubiquitin rich condensates triggers recruitment of the ATG9A lipid transfer complex to initiate basal autophagy.

Autophagy is an essential cellular recycling process that maintains protein and organelle homeostasis. ATG9A vesicle recruitment is a critical early step in autophagy to initiate autophagosome biogenesis. The mechanisms of ATG9A vesicle recruitment are best understood in the context of starvation-induced non-selective autophagy, whereas less is known about the signals driving ATG9A vesicle recruitment to autophagy initiation sites in the absence of nutrient stress. Here we demonstrate that loss of ATG9A or the lipid transfer protein ATG2 leads to the accumulation of phosphorylated p62 aggregates in the context of basal autophagy. Furthermore, we show that p62 degradation requires the lipid scramblase activity of ATG9A. Lastly, we present evidence that poly-ubiquitin is an essential signal that recruits ATG9A and mediates autophagy foci assembly in nutrient replete cells. Together, our data support a ubiquitin-driven model of ATG9A recruitment and autophagosome formation during basal autophagy.

Out-of-equilibrium quantum magnetism and thermalization in a spin-3 many-body dipolar lattice system.

Understanding quantum thermalization through entanglement build up in isolated quantum systems addresses fundamental questions on how unitary dynamics connects to statistical physics. Spin systems made of long-range interacting atoms offer an ideal experimental platform to investigate this question. Here, we study the spin dynamics and approach towards local thermal equilibrium of a macroscopic ensemble of S = 3 chromium atoms pinned in a three dimensional optical lattice and prepared in a pure coherent spin state, under the effect of magnetic dipole-dipole interactions. Our isolated system thermalizes under its own dynamics, reaching a steady state consistent with a thermal ensemble with a temperature dictated from the system's energy. The build up of quantum correlations during the dynamics is supported by comparison with an improved numerical quantum phase-space method. Our observations are consistent with a scenario of quantum thermalization linked to the growth of entanglement entropy.

Quantum liquid droplets in a mixture of Bose-Einstein condensates.

Quantum droplets are small clusters of atoms self-bound by the balance of attractive and repulsive forces. Here, we report on the observation of droplets solely stabilized by contact interactions in a mixture of two Bose-Einstein condensates. We demonstrate that they are several orders of magnitude more dilute than liquid helium by directly measuring their size and density via in situ imaging. We show that the droplets are stablized against collapse by quantum fluctuations and that they require a minimum atom number to be stable. Below that number, quantum pressure drives a liquid-to-gas transition that we map out as a function of interaction strength. These ultradilute isotropic liquids remain weakly interacting and constitute an ideal platform to benchmark quantum many-body theories.

Building confidence in quantitative systems pharmacology models: An engineer's guide to exploring the rationale in model design and development.

This tutorial promotes good practice for exploring the rationale of systems pharmacology models. A safety systems engineering inspired notation approach provides much needed rigor and transparency in development and application of models for therapeutic discovery and design of intervention strategies. Structured arguments over a model's development, underpinning biological knowledge, and analyses of model behaviors are constructed to determine the confidence that a model is fit for the purpose for which it will be applied.

Diet Switching by Mammalian Herbivores in Response to Exotic Grass Invasion.

Invasion by exotic grasses is a severe threat to the integrity of grassland ecosystems all over the world. Because grasslands are typically grazed by livestock and wildlife, the invasion is a community process modulated by herbivory. We hypothesized that the invasion of native South American grasslands by Eragrostis plana Nees, an exotic tussock-forming grass from Africa, could be deterred by grazing if grazers switched dietary preferences and included the invasive grass as a large proportion of their diets. Bos taurus (heifers) and Ovis aries (ewes) grazed plots with varying degrees of invasion by E. plana in a replicated manipulative experiment. Animal positions and species grazed were observed every minute in 45-min grazing session. Proportion of bites and steps in and out of E. plana tussocks were measured and used to calculate several indices of selectivity. Both heifers and ewes exhibited increasing probability of grazing E. plana as the proportion of area covered by tussocks increased, but they behaved differently. In agreement with expectations based on the allometry of dietary preferences and morphology, ewes consumed a low proportion of E. plana, except in areas that had more than 90% E. plana cover. Heifers consumed proportionally more E. plana than ewes. Contrary to our hypothesis, herbivores did not exhibit dietary switching towards the invasive grass. Moreover, they exhibited avoidance of the invasive grass and preference for short-statured native species, both of which should tend to enhance invasion. Unless invasive plants are highly palatable to livestock, the effect of grazing to deter the invasion is limited, due to the inherent avoidance of the invasive grass by the main grazers in the ecosystem, particularly sheep.

Pulsatile insulin has greater hypoglycemic effect than continuous delivery.

The relative hypoglycemic effects of pulsatile versus steadily infused insulin have been examined in six normal subjects in whom pancreatic insulin output was suppressed by somatostatin-14. Soluble insulin was infused continuously overnight on one occasion and on another occasion the same quantity was given in pulses of 2-min duration with a gap of 11 min. The mean plasma glucose concentrations were lower when pulsed insulin was given [mean for the last hour: 4.66 +/- 0.08 mmol/L (+/- SEM) versus 5.53 +/- 0.06 mmol/L (+/- SEM) for steady infusion], diverging significantly (P less than 0.05 paired t test) 7 h after the start of the study. The specific binding of 125I(A14)mono-iodo-insulin to monocytes was greater after pulsed insulin (2.9% with pulsed versus 2.4% with steadily infused insulin at tracer-only point; P less than 0.02 paired t test). Thus, intravenous insulin has greater hypoglycemic effect when pulsed, possibly mediated by greater insulin receptor binding.

Combined immunohistochemistry for gonadotropin-releasing hormone (GnRH) and pro-GnRH, and in situ hybridization for GnRH messenger ribonucleic acid in rat brain.

Experiments were performed to explore the distribution of neurons containing pro-GnRH and GnRH in the rat brain and to determine the correspondence of immunoreactive peptides and pro-GnRH mRNA. Using avidin-biotin immunohistochemistry on free floating vibratome sections it was found that pro-GnRH- and GnRH-containing cells exhibited a similar distribution within the preoptic area-basal hypothalamus region. Within individual neurons pro-GnRH was primarily detected in the cell soma and proximal fibers, whereas the decapeptide was present in cells, fibers, and nerve terminals. Combined avidin-biotin immunohistochemistry for GnRH or pro-GnRH peptides and in situ hybridization for pro-GnRH mRNA using a cRNA probe revealed that the peptides and mRNA could be detected in the same cells. In both male and female rats pro-GnRH mRNA was localized primarily in GnRH-containing cells; however, not all immunoreactive GnRH neurons contained detectable levels of pro-GnRH mRNA, and not all neurons containing pro-GnRH mRNA contained GnRH peptides. In proestrous females a close correlation existed between the total number of neurons containing GnRH and those containing pro-GnRH mRNA (r = 0.84-0.9), while in intact male rats the correlation was not as high (r = 0.56). These results document the distribution of pro-GnRH and GnRH in the rat preoptic area-basal hypothalamus and describe the extent of colocalization of GnRH peptide and pro-GnRH mRNA in proestrous females and intact male rats. Further work will determine how each of the molecular components is regulated during different reproductive states.

Clinical outcome in aggressively treated meningeal carcinomatosis.

OBJECTIVE: To critically evaluate the clinical outcome of patients with cytologically proved meningeal carcinomatosis and to identify factors associated with an improved outcome. DESIGN: A consecutive series of patients was identified from a cytopathology data base. The study period was from 1985 to 1990. Case records and results of radiologic investigations were reviewed; all patients were followed up until their deaths. SETTING: University hospital with a cancer center. PATIENTS: Thirty-six consecutive patients with cytologically proved meningeal carcinomatosis. Patients with lymphoma or leukemia were excluded. INTERVENTIONS: External beam radiation therapy, intrathecal chemotherapy via a ventricular catheter, and intravenous chemotherapy. MAIN OUTCOME MEASURES: Clinical assessment and survival. RESULTS: Symptoms improved in 15% of 33 treated patients. Response to treatment had no clear relationship with the age, site of involvement, or tumor type. Median survival for treated patients was only 9 weeks. Patients who received more than five intrareservoir chemotherapy treatments had a median survival of 23 weeks. Median survival for patients with breast carcinoma who received intravenous chemotherapy was 20 weeks, significantly better than that of patients not receiving intravenous chemotherapy. CONCLUSIONS: Survival is poor despite aggressive treatment. Intravenous chemotherapy may improve survival in patients with chemoresponsive primary tumors and deserves further study.

Clinical outcome in aggressively treated meningeal gliomatosis.

We reviewed 11 consecutive patients with an antemortem cytologic diagnosis of meningeal gliomatosis. In three patients, meningeal gliomatosis was diagnosed before surgical resection of the glioma. Three of five patients with anaplastic astrocytoma and one with oligodendroglioma improved with treatment. Patients with glioblastoma multiforme did not respond and had a median survival from the diagnosis of meningeal gliomatosis of only 8 weeks. Meningeal gliomatosis can be an early finding in gliomas. Treatment response is probably related to tumor histology and grade.

Monoclonal antibodies from Epstein-Barr virus-transformed lymphocytes of common marmosets (Callithrix jacchus) immune to malaria.

The B lymphocytes of the common marmoset Callithrix jacchus can be immortalized by infection with Epstein-Barr virus (EBV) in vitro (Desgranges et al., 1976). C. jacchus is susceptible to infection with the blood stages of several species of malaria parasite including the line designated MVF1 (Mitchell et al., 1988) from which it recovers and shows immunity to reinfection. By exploiting these two phenomena, EBV-transformed, marmoset lymphoblastoid cell lines secreting antibodies to malaria parasite antigens have been generated and cloned. We believe this to be the first time that monoclonal antibodies (MAbs) have been raised from common marmosets. Since numerous and diverse human pathogens can infect this small primate in the laboratory, these methods may prove generally applicable for the generation of MAbs whose specificities derive from immune responses to infection.

Pneumocystis carinii pneumonia. Cytologic manifestations and rapid diagnosis in routinely prepared Papanicolaou-stained preparations.

In this study of 28 immunocompromised patients, it was found that Pneumocystis carinii pneumonia could be easily and reliably diagnosed by examination of routinely prepared, Papanicolaou-stained cellular samples obtained by bronchoalveolar lavage, bronchial brushing, and bronchial washing. The distinctive intra-alveolar exudate of pneumocystosis observed in lung biopsy specimens was readily discernible in all of the cellular samples that demonstrated P. carinii by special stains. The exudate was not present in any of the P. carinii-negative samples. Routinely prepared, Papanicolaou-stained cellular samples can be relied upon for the rapid diagnosis of P. carinii pneumonia.

Fine needle aspiration cytology of the breast. An overview.

With the development of the Breast Care Center in the University of Michigan, we experienced over a 4-year period a 1,200% increase in the number of breast aspirates received annually in our cytopathology laboratory. During this period, as newcomers to breast aspiration cytology, we achieved an 81.4% positive diagnosis rate in 161 cases of breast cancer without any false positives. This article reviews our experience with fine-needle aspiration cytology of the breast with particular reference to (a) procurement of specimens, (b) cytopathology of benign lesions, (c) cytopathology of malignant lesions, and (d) advantages of the procedure.

Effects of oestradiol and progesterone on the in vitro production of prostaglandin F2alpha by the guinea-pig uterus.

1 The effects of oestradiol and progesterone on the production of F 2alpha by the guinea-pig uterus in vitro have been studied. 2 Ovariectomized guinea-pigs were treated with oestradiol benzoate, progesterone, or a combination of these hormones. The uteri were homogenized and incubated and the prostaglandin F2alpha produced was measured by radiommunoassay or combined gas chromatography-mass spectrometry (g.c.-m.s.). Oestradiol treatment or progesterone followed by oestradiol caused a significant increase in prostaglandin F2alpha synthesis compared with control values, whereas progesterone treatment caused no significant increase. 3 The uteri from guinea-pigs on day 7 of the oestrous cycle were split into four parts, and each part homogenized and incubated either alone or in the presence of oestradiol-17beta, progesterone, or a combination of these hormones. Prostaglandin F2alpha was measured by g.c.-m.s. Oestradiol was found to increase prostaglandin F2alpha synthesis by the uterus whereas progesterone had no effect. However, progesterone did inhibit the response to oestradiol. 4 Oestradiol treatment of the guinea-pig uterus causes an increase in capacity to produce prostaglandin F2alpha in vitro. The role of progesterone is difficult to interpret.

Production of prostaglandins by the pseudopregnant rat uterus, in vitro, and the effect of tamoxifen with the identification of 6-keto-prostaglandin F1alpha as a major product.

1 Prostaglandin production by rat uterus homogenates has been studied, in vitro, on days 2 to 13 of pseudopregnancy. 2 The highest production of prostaglandins occurred on day 5. 3 The amounts of prostaglandins F and D formed were higher than the amounts of prostaglandin E on every day studied. 4 The ratios of prostglandins F and D to prostaglandin E produced steadily decreased up to day 6. It then increased with the highest values occurring between days 10 and 13, 5 Progesterone levels in peripheral plasma increased rapidly from days 2 to 5, remained high up to day 9, then steadily decreased between days 10 and 13. 6 The anti-oestrogenic drug, tamoxifen administered on day 2, significantly inhibited the increase of prostaglandin production which occurred on day 5. Prostaglandin E production was inhibited more than the production of prostaglandins F and D. 7 Analysis of the uterine extracts by gas chromatography and mass spectrometry showed prostaglandin F2alpha, F1alpha (in trace amounts), E2 and D2 to be present. 8 The major product detected was 6-keto-prostaglandin F1alpha. Its identification forms an addendum to the paper. 9 Also present as a major product was 6(9)-oxy-11,15-dihydroxyprosta-7,13-dienoic acid.

Low-dose amphotericin B therapy for acute pulmonary histoplasmosis.

A patient wtih acute epidemic pulmonary histoplasmosis was treated with 500 mg of amphotericin B. Traditionally, such patients have not been treated, since the illness is usually self-limited; however, fatalities have been reported, and some authorities have recommended therapy with small doses of amphotericin B. Patients with acute pulmonary histoplasmosis who are acutely ill should be considered for low-dose treatment with amphotericin B, inasmuch as they are likely candidates for early dissemination. Cures have been reported with as little as 105 mg of amphotericin B administered intravenously.

Idiopathic pulmonary hypertension associated with nodular pulmonary infiltrates and portal venous thrombosis.

A case of idiopathic pulmonary hypertension is associated with portal venous thrombosis. The patient's chest roentgenogram revealed numerous nodular densities which at necropsy were found to have been caused by an exuberant fibroblastic reaction around small pulmonary arterioles. This is an example of the unusual association of idiopathic pulmonary hypertension and portal venous thrombosis, and to our knowledge, the first report of roentgenographically visible pulmonary nodules secondary to the pathologic alterations of idiopathic pulmonary hypertension.