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Everybody knows--or thinks they know--Charles Darwin, the father of evolution and the man who altered the way we view our place in the world. But what most people do not know is that Darwin was on board the HMS Beagle as a geologist--on a mission to examine the land, not flora and fauna. Retracing Darwin's footsteps in South America and beyond, geologist Rob Wesson treks across the Andes, cruises waters charted by the Beagle, hunts for fossils in Uruguay and Argentina, and explores sites of long vanished glaciers in Scotland and Wales. As he follows Darwin's path--literally and intellectually--Wesson experiences the land as Darwin did, engages with his observations, and tackles the same questions Darwin had about our ever-changing Earth. Upon his return from his five-year journey aboard the Beagle, after examining the effects of earthquakes, tsunamis, volcanic eruptions, and more, Darwin conceived his theory of subsidence and uplift--his first theory. These concepts and attitudes--the vastness of time; the enormous cumulative impact of almost imperceptibly slow change; change as a constant feature of the environment--underlie Darwin's subsequent discoveries in evolution. And this peculiar way of thinking remains vitally important today as we enter the human-dominated Anthropocene age. Expertly interweaving science and adventure, Darwin's First Theory is a riveting and revelatory journey around the world with one of the greatest scientific minds in history.

The clinical opiate withdrawal scale (COWS) is a clinician-administered, pen and paper instrument that rates eleven common opiate withdrawal signs or symptoms. The summed score of the eleven items can be used to assess a patient's level of opiate withdrawal and to make inferences about their level of physical dependence on opioids. With increasing use of opioids for treatment of pain and the availability of sublingual buprenorphine in the United States for treatment of opioid dependence, clinical assessment of opiate withdrawal intensity has received renewed interest. Buprenorphine, a partial opiate agonist at the mu receptor, can precipitate opiate withdrawal in patients with a high level of opioid dependence who are not experiencing opioid withdrawal. Since development of the first opiate withdrawal scale in the mid-1930s, many different opioid withdrawal scales have been used in clinical and research settings. This article reviews the history of opiate withdrawal scales and the context of their initial use. A template version of the COWS that can be copied and used clinically is appended. PDF formatted versions of the COWS are also available from the websites of the American Society of Addiction Medicine, the California Society of Addiction Medicine, the UCLA Integrated Substance Abuse Programs, and AlcoholMD.com .

Planetary nebulae (PNe) are remnants of evolved stars, fundamental for understanding stellar life cycles and galactic enrichment. In this work, we present a summary of our recent work using three-dimensional models and spatially resolved constraints to examine the physical and chemical properties of PNe, with a particular focus on preliminary results for the PN NGC 3132. Our results indicate that a star of about 3M⊙, surrounded by a shell, wind, or disk with approximately 5.0×10−6M⊙ and extending to about 300AU is necessary to adequately reproduce the observations, consistent with recent JWST findings. We also discuss the importance of this methodology in studying the properties of the progenitor stars and making abundance determinations.

Water features in old stars The discovery in 2001 of water vapour around the ageing carbon star IRC+10216 was a surprise, because stellar evolution models predicted the virtual absence of water in carbon-rich stars. Several explanations were offered, but with only one water line detected in the spectrum of one carbon-rich evolved star, it was difficult to discriminate between the alternatives. Now observations with the European Space Agency's Herschel satellite have discovered dozens of water lines in the far-infrared and submillimetre spectrum of IRC+10216. These include high-excitation lines with energies corresponding to temperatures of around 1,000 K, which can be explained only if water is present in the warm inner sooty region of the envelope. Water has been predicted to be almost absent in carbon-rich stars, so the detection of water vapour around the ageing carbon star IRC + 10216 challenged our understanding of the chemistry in old stars. Several explanations for the water have been postulated, but with only one water line detected it is difficult to discriminate between them. Now, dozens of water vapour lines have been detected in the far-infrared and sub-millimetre spectrum of IRC + 10216. The detection 1 of circumstellar water vapour around the ageing carbon star IRC +10216 challenged the current understanding of chemistry in old stars, because water was predicted 2 to be almost absent in carbon-rich stars. Several explanations for the water were postulated, including the vaporization of icy bodies (comets or dwarf planets) in orbit around the star 1 , grain surface reactions 3 , and photochemistry in the outer circumstellar envelope 4 . With a single water line detected so far from this one carbon-rich evolved star, it is difficult to discriminate between the different mechanisms proposed. Here we report the detection of dozens of water vapour lines in the far-infrared and sub-millimetre spectrum of IRC +10216 using the Herschel satellite 5 . This includes some high-excitation lines with energies corresponding to ∼1,000 K, which can be explained only if water is present in the warm inner sooty region of the envelope. A plausible explanation for the warm water appears to be the penetration of ultraviolet photons deep into a clumpy circumstellar envelope. This mechanism also triggers the formation of other molecules, such as ammonia, whose observed abundances 6 are much higher than hitherto predicted 7 .

We present JWST images of NGC 6720 (the Ring Nebula), covering wavelengths from 1.6 μm to 25 μm. The bright shell is strongly fragmented with some 20 000 dense globules, bright in H2, with a characteristic diameter of 0.2 arcsec and density nH∼105–106cm−3. The shell contains a narrow ring of polycyclic aromatic hydrocarbon (PAH) emission. H2 is found throughout the shell and also in the halo. The central cavity is filled with high ionization gas and shows two linear structures seen in projection against the cavity. The central star is located 2 arcsec from the emission centroid of the cavity and shell. Linear features (‘spikes’) extend outward from the ring, pointing away from the central star. Around ten low-contrast, regularly spaced concentric arc-like features are present; they suggest orbital modulation by a low-mass companion with a period of about 280 yr. A previously known much wider companion is located at a projected separation of about 15 000 au; we show that it is an M2–M4 dwarf. NGC 6720 is therefore a triple star system. These features, including the multiplicity, are similar to those seen in the Southern Ring Nebula (NGC 3132) and may be a common aspect of such nebulae.

Aims. To evaluate the safety and efficacy of an 8 mg/day sublingual dose of buprenorphine in the maintenance treatment of heroin addicts by comparison with a 1 mg/day dose over a 16‐week treatment period. As a secondary objective, outcomes were determined concurrently for patients treated with two other dose levels . Design. Patients were randomized to four dosage groups and treated double‐blind . Setting. Twelve outpatient opiate maintenance treatment centers throughout the United States . Participants. Two hundred and thirty‐nine women and 497 men who met the DSM‐III‐R criteria for opioid dependence and were seeking treatment . Intervention. Patients received either 1, 4, 8 or 16 mg/day of buprenorphine and were treated in the usual clinical context, including a 1‐hour weekly clinical counseling session . Measurement. Retention in treatment, illicit opioid use as determined by urine toxicology, opioid craving and global ratings by patient and staff. Safety outcome measures were provided by clinical monitoring and by analysis of the reported adverse events . Findings. Outcomes in the 8 mg group were significantly better than in the 1 mg group in all four efficacy domains. No deaths occurred in either group. The 8 mg group did not show an increase in the frequency of adverse events. Most reported adverse effects were those commonly seen in patients treated with opioids . Conclusions. The findings support the safety and efficacy of buprenorphine and suggest that an adequate dose of buprenorphine will be a useful addition to pharmacotherapy.

Compelling clinical evidence establishes that buprenorphine is similar to methadone in efficacy for opiate detoxification and maintenance but safer than methadone in an overdose situation. The Drug Abuse Treatment Act of 2000 (DATA 2000) enabled US physicians with additional training to prescribe buprenorphine to a limited number of opiate-dependent patients. The sublingual tablets Subutex® (buprenorphine alone) and Suboxone® (a combination of buprenorphine and naloxone) meet the specifications of DATA 2000. Suboxone is intended to discourage intravenously administration and has less abuse potential than buprenorphine alone. Suboxone is generally recommended for maintenance treatment except for women who are pregnant. Subutex is recommended in treatment of pregnant women. A buprenorphine opiate withdrawal syndrome can occur in newborns. Although intravenous buprenorphine abuse is a significant public health problem in some countries, buprenorphine alone or in combination with naloxone has less potential for abuse than heroin and some prescription opiates, such as oxycodone. Pharmacotherapy from physicians' offices makes buprenorphine treatment acceptable to some opiate-dependent patients who would not accept treatment in traditional opiate-maintenance clinics. For reasons not adequately understood, some patients find discontinuation of buprenorphine following long-term use difficult. This article reviews the pharmacology of buprenorphine, summarizes evidence supporting the safety and efficacy of buprenorphine and provides clinical guidelines for treatment.

Motivated by the recent establishment of a connection between central star binarity and extreme abundance discrepancies in planetary nebulae, we have carried out a spectroscopic survey targeting planetary nebula with binary central stars and previously unmeasured recombination line abundances. We have discovered seven new extreme abundance discrepancies, confirming that binarity is key to understanding the abundance discrepancy problem. Analysis of all 15 objects with a binary central star and a measured abundance discrepancy suggests a cut-off period of about 1.15 days, below which extreme abundance discrepancies are found.

We present observations of nearby red supergiants with SPHERE.

Recent work (Corradi et al. 2015; Jones et al. 2016) has shown that the phenomenon of extreme abundance discrepancies, where recombination line abundances exceed collisionally excited line abundances by factors of 10 or more, seem to be strongly associated with planetary nebulae with close binary central stars. To further investigate, we have obtained spectra of a sample of nebulae with known close binary central stars, using FORS2 on the VLT, and we have discovered several new extreme abundance discrepancy objects. We did not find any non-extreme discrepancies, suggesting that a very high fraction of nebulae with close binary central stars also have an extreme abundance discrepancy.