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Over four decades ago, pulsed-laser melting, or pulsed-laser annealing as it was termed at that time, was the subject of intense study as a potential advance in silicon device processing. In particular, it was found that nanosecond laser melting of the near-surface of silicon and subsequent liquid phase epitaxy could not only very effectively remove lattice disorder following ion implantation, but could achieve dopant electrical activities exceeding equilibrium solubility limits. However, when it was realised that solid phase annealing at longer time scales could achieve similar results, interest in pulsed-laser melting waned for over two decades as a processing method for silicon devices. With the emergence of flat panel displays in the 1990s, pulsed-laser melting was found to offer an attractive solution for large area crystallisation of amorphous silicon and dopant activation. This method gave improved thin film transistors used in the panel backplane to define the pixelation of displays. For this application, ultra-rapid pulsed laser melting remains the crystallisation method of choice since the heating is confined to the silicon thin film and the underlying glass or plastic substrates are protected from thermal degradation. This article will be organised chronologically, but treatment naturally divides into the two main topics: (1) an electrical doping research focus up until around 2000, and (2) optical doping as the research focus after that time. In the first part of this article, the early pulsed-laser annealing studies for electrical doping of silicon are reviewed, followed by the more recent use of pulsed-lasers for flat panel display fabrication. In terms of the second topic of this review, optical doping of silicon for efficient infrared light detection, this process requires deep level impurities to be introduced into the silicon lattice at high concentrations to form an intermediate band within the silicon bandgap. The chalcogen elements and then transition metals were investigated from the early 2000s since they can provide the required deep levels in silicon. However, their low solid solubilities necessitated ultra-rapid pulsed-laser melting to achieve supersaturation in silicon many orders of magnitude beyond the equilibrium solid solubility. Although infrared light absorption has been demonstrated using this approach, significant challenges were encountered in attempting to achieve efficient optical doping in such cases, or hyperdoping as it has been termed. Issues that limit this approach include: lateral and surface impurity segregation during solidification from the melt, leading to defective filaments throughout the doped layer; and poor efficiency of collection of photo-induced carriers necessary for the fabrication of photodetectors. The history and current status of optical hyperdoping of silicon with deep level impurities is reviewed in the second part of this article.

Capsule: Recording of behavioural responses to ferry traffic for 11 target species showed that Red-throated Diver Gavia stellata, Slavonian Grebe Podiceps auratus, and Black-throated Diver Gavia arctica were most likely to react to passing vessels. Aim: To provide information on how responses to marine traffic vary between waterbird species to inform marine spatial planning and environmental impact assessments in the near-shore environment. Methods: We recorded behavioural responses to ferry traffic for 11 target species in near-shore waters: Common Eider Somateria mollissima, Goldeneye Bucephala clangula, Long-tailed Duck Clangula hyemalis, Velvet Scoter Melanitta fusca, Red-breasted Merganser Mergus serrator, Black-throated Diver, Great Northern Diver Gavia immer, Red-throated Diver, European Shag Gulosus aristotelis, Slavonian Grebe and Black Guillemot Cepphus grylle. Responses were analysed using generalized linear models and mixed models. Results: Red-throated Diver, Black-throated Diver and Slavonian Grebe were the most likely species to exhibit a response to passing vessels. While Red-throated Divers and Slavonian Grebes were highly likely to flush, Black-throated Divers and Great Northern Divers rarely took flight, instead favouring swim or dive responses. In rougher sea conditions birds were more likely to take flight, and the propensity to respond declined across the wintering period. Conclusions: This research provides comparative evidence on the behavioural responses of waterbirds to marine traffic. The results support previous studies which highlighted the high sensitivity of diver species to disturbance and provide new evidence that Slavonian Grebe may also be a high sensitivity species.

North American leaders recently committed to reducing methane emissions from the oil and gas sector, but information on current emissions from Canadian unconventional developments is lacking. This study examined the incidence of methane in an area of unconventional natural gas development in northwestern Canada. In August to September 2015 we completed almost 8000 km of vehicle-based survey campaigns on public roads dissecting developments that mainly access the Montney formation in northeastern British Columbia. Six survey routes were repeated 3–6 times and brought us past over 1600 unique well pads and facilities developed by more than 50 different operators. To attribute on-road plumes to infrastructural sources we used gas signatures of residual excess concentrations (anomalies above background) less than 500 m downwind from infrastructural sources. All results represent emissions greater than our minimum detection limit of 0.59 g/s at our average detection distance (319 m). Unlike many other developments in the US for which methane measurements have been reported recently, the methane concentrations we measured at surface were close to normal atmospheric levels, except inside natural gas plumes. Roughly 47 % of active wells emitted methane-rich plumes above our minimum detection limit. Abandoned and under-development well sites also emitted methane-rich plumes, but the incidence rate was below that of producing wells. Multiple sites that pre-date the recent unconventional Montney development were found to be emitting, and in general we observed that older infrastructure tended to emit more often (per unit) with comparable severity in terms of measured excess concentrations on-road. We also observed emissions from facilities of various types that were highly repeatable. Emission patterns in this area were best explained by infrastructure age and type. Extrapolating our results across the Montney development, we estimate that the emission sources we located (emitting at a rate > 0.59 g/s) contribute more than 111,800 tonnes of methane annually to the atmosphere. This value exceeds reported bottom-up estimates of 78,000 tonnes for all oil and gas sector sources in British Columbia, of which the Montney represents about 55 % of production. The results also demonstrate that mobile surveys could be used to exhaustively screen developments for super-emitters, because without our intensive 6-fold replication we could have used single-pass sampling to screen 80 % of Montney-related infrastructure. This is the first bottom-up study of fugitive emissions in the Canadian energy sector, and these results can be used to inform policy development in an era of methane emission reduction efforts.

In this essay I review two books of rather different focus, but with a common thread that is oral tradition: age-old tales passed orally down the generations to maintain the histories and used to educate the young. The focus of the Metge book is traditional methods of education, while McRae’s focus is on the stories themselves.

Groundwater methane (CH4) in areas of fossil fuel development has been a recent focus of study as high CH4 concentrations pose water quality concerns and potential explosive hazards. In 2013, a provincial study in Nova Scotia identified areas with elevated groundwater CH4. However, due to limited data, the specific sources and local distribution of CH4 in those areas remain unknown. In this study, we examined the Stellarton Basin in central Nova Scotia, Canada, a region with an abundance of coal formations, numerous abandoned coal mines, and an active open pit coal mine. Methane was detected in 94% of water samples that were sampled from 45 private water wells. Six water wells exceeded the 28 mg/L hazard mitigation threshold with CH4 levels of up to 72.7 mg/L. The δ13CCH4 (−85.5 to −48.5‰) and the δ2HCH4 (−280 to −88‰) indicated that >95% of samples had CH4 of microbial origin. However, the detection of ethane (C2H6) up to 2.97 mg/L and propane (C3H8) up to 0.008 mg/L, as well as the δ13CC2H6 values (−30.1 to −15.6‰) suggested a mixture of microbial CH4 with trace thermogenic gas, likely migrated from Stellarton coals (δ13CC2H6 of −27.6 to −15.35‰). A mobile greenhouse gas analyzer survey was conducted within the perimeter of residences and off-gassing from taps had atmospheric CH4 measurements as high as 66 ppmv. This study integrates multiple sampling and monitoring methods to investigate groundwater CH4 in a coal-bearing region. The findings advance the understanding of the origin and occurrence of CH4 in complex groundwater systems. The data acquired in this study may be used as a pre-drill baseline for groundwater CH4 concentrations and origins should coal-bed methane operations in Nova Scotia proceed in the future.

The paper argues that by the time of European contact Ngāi Tahu, the southernmost Māori had developed a regime of sustainable practices for the management of natural resources. Some of these practices are described. As traditional society, in the south, is located in a rather different cultural milieu than that occupied by Māori who lived in areas where kūmera harvests were reliable, an attempt is made to position Southern Ngāi Tahu in relation to the dominant anthropological paradigms, as an agricultural people may seem to have regressed to become primarily hunters and gatherers.

Following the discovery of a Bronze Age log boat in Shardlow Quarry, Derbyshire in 2003, a scheme was devised to preserve this boat in situ. This included a monitoring programme to ensure that reducing conditions were maintained. This solution was agreed by the mineral planning authority Derbyshire County Council, with input and advice from English Heritage.Monitoring lasted ten years, during which time gravel deposits surrounding the boat were extracted. The boat was protected from dewatering during this time by a clay cut-off, installed around the area containing the boat before extraction begun. After extraction the adjacent areas were backfilled with on-site soils and inert waste.Data indicate that a reducing environment has been largely sustained during this period. Following careful and considered discussion, the monitoring programme ceased as there was unlikely to be further impacts to site hydrology, making additional data collection redundant.

Concern exists regarding the long-term viability of the internationally important archaeological remains of the Flag Fen site near Peterborough. This paper describes a hydrogeological numerical groundwater model which has been used to understand the groundwater situation with regard to the archaeology, including drainage impacts, and also to explore future scenarios. Observed and modelled groundwater levels have been interpreted using three zones: the ‘dry’ zone 1 above the seasonal maximum water table; zone 2 of seasonal water table fluctuation; and a deeper zone 3 of permanent saturation. Archaeological wood is best preserved in Zone 3. Much of the Bronze Age wooden structure is located within Zone 2 or above. The hydrological conditions are therefore not ideal for the long-term in situ preservation of the material. Groundwater modelling indicates that the main factor controlling groundwater levels in the area is artificial drainage. The approach would be applicable to other wet-preserved archaeological...

Energy reserves have been exploited in the Atlantic Canadian provinces since the early 1600s, and many fossil fuel extraction sites have been abandoned over this long history of energy development. Oil, natural gas, and coal extraction sites are a source of greenhouse gas emissions, particularly for methane (CH4). In this study, we used multiple sampling methods to measure CH4 from abandoned coal mine openings in Nova Scotia and a legacy oilfield in New Brunswick. Atmospheric and shallow soil gases were sampled around legacy sites using flux rate chamber measurements (spatial and temporal) and plot-scale atmospheric gas surveys, in addition to regional gas screening surveys over larger populations of sites to confirm whether small-scale observations were reflected regionally. Only one oil and gas site (2.4 ± 3.1⋅ 102 mg m− 2 day− 1) and one abandoned coal mine opening (1.0 ± 1.1⋅ 102 mg m− 2 day− 1) were affected by soil CH4 migration, though rates of leakage were minimal and would rank as low severity on industrial scales. Plot-scale atmospheric gas screening showed super-ambient CH4 concentrations at 5 sites in total (n = 16), 2 coal adits and 3 abandoned oil and gas wells. Regional gas screening surveys suggest that 11% of legacy oil and gas sites have some emission impacts, compared with 1–2% of legacy coal sites. These frequencies are close, albeit lower than the 15% of legacy oil and gas sites and 10% of abandoned coal mine openings flagged from our aggregated small-scale observations. These sites may emit less than other developments studied to date either because more time has elapsed since extraction, or because differences in regional geology reduce the likelihood of sustained emissions. This study provides valuable information to help understand the methane emission risks associated with legacy energy sites.

An unknown population of Medionidus simpsonianus (Ochlockonee Moccasinshell) was discovered in the lower Ochlockonee River downstream of Jackson Bluff Dam in 2014. This discovery confirms that the species is extant, extends its known range by nearly 100 rkm, and represents only the second known collection of this species in the lower Ochlockonee River Basin. Ochlockonee Moccasinshell is endemic to the Ochlockonee River Basin (ORB) in Florida and Georgia. It was historically known from 9 locations in the upper ORB upstream of Lake Talquin and from 1 record in the lower ORB downstream of Jackson Bluff Dam. Collections of Ochlockonee Moccasinshell decrease in regularity after 1950, and the last record of a live individual was 1995. We surveyed 55 sites downstream of Jackson Bluff Dam in a reach of river having received little effort in the last 20 years. We employed visual/tactile searches using mask and snorkel from shore to a depth of 2.5 m and found 22 live individuals of Ochlockonee Moccasinshel...

In the spring of 2007, a small number of empty valves from the bay scallop, Argopecten irradians irradians (Lamarck), were observed at several locations in Pomquet Harbour, Nova Scotia, Canada. Snorkeling surveys at selected sites in the harbor were carried out in spring 2007, summer 2007, and spring 2008. Scallop densities were very low in all sampling times, ranging between 0.04 and 0.053 scallops/m2. The size distributions from 2007 suggested a single cohort of 0 + individuals, with one 1 + scallop. The 2008 samples were predominantly 1 + scallops, with five 0 + individuals. Four marked scallops from 2007 were collected alive in 2008, demonstrating their ability to overwinter. These scallops had an average daily growth rate of 0.08 mm/day from July 2007 to May 2008. A thermistor deployed in the same eelgrass beds indicated that the scallops survived extended periods of time with temperatures below 0°C. In 2013, four of the sites were surveyed again, and dramatic increases in density were recor...

Diagnosis and treatment of diabetes changed little from the Middle Ages through the early 19th century, when the first chemical test for the condition was developed. In the 20th century, advances in diabetes management gained momentum with home-use diagnostic devices and mass-produced insulin. In the 21st century, technological developments around diabetes are advancing so rapidly that a small, discrete system of medical devices that serve as an artificial pancreas are now possible. In this article, we assert that medical device interoperability and cyber security are necessary preconditions for safe, effective, and reliable widespread use of the artificial pancreas system.

Feeding behaviors may differ between past and current predators due to differences in the environments inhabited by these species at different times. We provide an example of this behavioral variability in spotted hyena (Crocuta crocuta), for which our analysis of a late Pleistocene micromammal assemblage indicates that hyenas preyed upon small rodents, a feeding habit that is rarely observed today among hyenas. The Bois Roche cave site is situated at the edge of a low bluff overlooking the floodplain of a small stream in Cherves-Richemont (Charente, France). The deposits are dated by electron spin resonance (ESR) to about 69.7 ± 4.1 Ka. Excavations at the site recovered fossil bones and teeth of large and small mammals, together with hyena coprolites. Water screening of the sediments produced large accumulations of rodent remains with low taxonomic diversity. Small mammal bones were recovered from hyena coprolites as well. Descriptions of small mammal bone modification, both from the sediments and coprolites, are reported here. The analysis yielded a distinct taphonomic pattern representative of large carnivores (over 30 kg), which differs from any other modern or fossil predator-accumulated microfaunal assemblage taphonomically analyzed to date. To our knowledge, previous studies of hyena diet have not recorded high concentrations of a single-rodent prey species. We conclude that the low species diversity of this small mammal assemblage most likely relates to a local abundance of the prey species due to an outbreak in the rodent population, rather than from specialist predator behavior and hunting technique., This investigation has benefited from projects CGL2007-66231 and CGL2016-79334P of the Spanish Ministry of Research. The Bois Roche excavations were funded by the French Ministry of Culture, the Leakey Foundation, the National Science Foundation, the General Council of the Charente Region, the Association of Archeologists of the Poitou-Charente Region, and Franklin and Marshall College.

As history is usually recorded by the victors, it is instructive to have an opportunity to contrast a perspective from the vanquished. However, when both parties are from colonized minorities, and there is also a colonizer's view, the opportunity exists for the almost unique comparison of one etic and two emic accounts. The battle of Crowheart Butte, Wyoming, in 1866, provides such an opportunity, illustrating how each group maintains its own historicity and how the different versions can offer some additional insight into one another.

In 2001–2002, there were severe declines of eelgrass (Zostera marina) in estuaries along the Nova Scotia coast of the southern Gulf of St. Lawrence. We examined the relationship between the recent invasion of European green crabs (Carcinus maenas) and the eelgrass decline in Benoit Cove in Tracadie Harbour. The abnormally abundant eelgrass wrack consisted mainly of entire shoots, not the usual blades. Three separate methods yielded similar estimates of the rate of shoot removal from the eelgrass beds (direct quadrat counts, “mark–recapture” of tagged shoots in the eelgrass bed, and rate of shoot appearance in the shore wrack). From 14 July to 8 September 2002, the shoot density in the bed fell by about 75 %. Similar rates of decline occurred in crab enclosures (4.4 crabs m−2) placed in the eelgrass bed. Green crab foraging, involving the tearing of shoots and the digging of large pits, was the reason for the drastic decline of the eelgrass bed in Benoit Cove. It is clear that an invasion of green crabs to a region where they had not previously existed can both destroy eelgrass beds and restrict their recovery.

Recent years have seen the emergence of regular activities, each June in New Zealand, to coincide with what is usually referred to as “The Māori New Year”, generally known as “Matariki”. However, within my tribal area, as well as in a number of others, the term “Puaka” was used instead. The article examines these differing tribal traditions and proposes a possible explanation for the two schools of thought.

Over the last thirty years, over sixty separate episodes of monitoring waterlogged archaeological sites have been carried out in England. This paper lists these projects, summarizes basic information about them, and reviews what we have learnt over these last thirty years. Recommendations are given to help improve future monitoring projects. In particular, it is suggested that more work is needed on assessing the state of preservation of a site before monitoring is considered; that a proper project design needs to be developed at the outset of the work; and that more thought should go into deciding why monitoring is needed for a given site, including identifying mitigation options that can be initiated if monitoring data suggest optimum conditions for survival are no longer being maintained.

Most population estimates of American lobster (Homarus americanus) rely on catch data from the commercial fishery. Therefore, it is important to understand the factors that affect the catchability of lobsters and their behavioural response to traps. Commercial fishermen claim that if lobster traps are fished in linked sets, or trawls, that the trap that is adjacent to the surface buoy generally has a lower catch, presumably because of increased trap movement due to more direct exposure to wind influence. For four consecutive weeks during May and June 2007, we recorded the catch of 944 trap hauls to determine if there are differences in lobster catch rates among the four linked traps on a line, and if these differences are related to wind speed. In addition, on the second and fourth week of the study, every second trawl received a gear modification designed to decrease the effect of the wind on catch rates. The study found that there were no significant differences in catch rate among the four traps in a trawl. Although wind and catch rate were expected to be somehow related, no meaningful linear relationship between these variables was found. These results indicate that common assumptions about the effects of gear design on lobster catch rate may not be supported when examined systematically, and that relationships between wind, temperature and catch rate are not always evident.