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In 2021, a catastrophic flood occurred in the Melamchi Valley of Nepal, causing widely distributed erosion in Himalayan headwaters and mobilizing a large sediment volume. As the flood progressed downstream, it induced an erosional cascade, producing 100 m deep incisions into high-elevation valley fills, generating new landslides and burying the lower reaches in alluvium. This event demonstrated the destructive impact of cascading processes and their potential for reshaping the landscape.

BackgroundThere is scant research on methods used to identify counterfeit Marlboro cigarettes.MethodsSystematic analysis of internal tobacco industry documents characteristics of counterfeit Marlboro cigarettes.ResultsIn the industry documents we identified as relevant, there were 42 characteristics of counterfeit Marlboro cigarettes. Overall, physical characteristics (88.1%) were the most commonly identified features across all locations, with the pack blank, cardboard shell of the cigarette pack, as the dominant site (30.9%). Some of the physical characteristics included offset lithography printing, incorrect font and colour. Overall, light microscopy was identified as the main method of forensic analysis for detecting counterfeits.ConclusionIndependent researchers employing litter pack and pack swap surveys are encouraged to use the characteristics identified in the study to gauge the prevalence of counterfeit Marlboro cigarettes and compare against industry estimates.

IntroductionIn 2009, New York City (NYC) restricted the sale of flavoured tobacco products. We assessed product availability as a proxy for potential non-compliance by analysing discarded cigar, cigarillo and blunt wrap packages in New York City.MethodsA discarded cigar package survey was conducted in 2016, in a stratified random sample of 94 block groups in NYC resulting in the collection of 886 discarded cigar packages. Each package was coded for brand name, flavour description (explicit and implicit) and size.FindingsOverall, 19.2% of the cigar packages were explicitly flavoured. An additional 9.4% of the packages reflected implicit flavours. Explicit flavoured cigar packages were at increased odds of being found in Staten Island (adjusted OR (AOR)=3.96, 95% CI=1.66 to 9.46), in packaging size of two or three (AOR=8.49, 95% CI=4.24 to 17.02) or four or more (AOR=4.26, 95% CI=1.95 to 9.30).ConclusionNearly one out of three cigar packages were flavoured products suggesting a problematic level of non-compliance and continued availability. Potential non-compliance is likely fueled by licensed wholesalers and retailers who continue to sell restricted flavoured products. Some retailers may be unaware that implicitly named cigars are typically flavoured and are, therefore, illegal. This lack of awareness of implicit flavoured cigars may be exacerbated by NYC’s lack of education or enforcement specific to implicitly flavoured tobacco products.

Perinatal hypoxia-ischemia remains a significant cause of neonatal mortality and neurodevelopmental disability. Numerous lines of evidence indicate that cerebral ischemic insults disrupt normal respiratory activity in mitochondria. Carnitine (3-hydroxy-4-N-trimethylammonium-butyrate) has an essential role in fatty acid transport in the mitochondrion and in modulating potentially toxic acyl-CoA levels in the mitochondrial matrix. There are no naturally occurring esterases available to reduce the accumulation of acyl-CoA but this process can be overcome by exogenous carnitine. We used a newborn rat model of perinatal hypoxia-ischemia to test the hypothesis that treatment with l-carnitine would reduce the neuropathologic injury resulting from hypoxia-ischemia in the developing brain. We found that treatment with l-carnitine during hypoxia-ischemia reduces neurologic injury in the immature rat after both a 7- and 28-d recovery period. We saw no neuroprotective effect when l-carnitine was administered after hypoxia-ischemia. Treatment with d-carnitine resulted in an increase in mortality during hypoxia-ischemia. Carnitine is easy to administer, has low toxicity, and is routinely used in neonates as well as children with epilepsy, cardiomyopathy, and inborn errors of metabolism. l-Carnitine merits further investigation as a treatment modality for the asphyxiated newborn or as prophylaxis for the at-risk fetus or newborn.

Perinatal hypoxia-ischemia remains a significant cause of neonatal mortality and neurodevelopmental disability. Numerous lines of evidence indicate that cerebral ischemic insults disrupt normal respiratory activity in mitochondria. Carnitine (3-hydroxy-4-N-trimethylammonium-butyrate) has an essential role in fatty acid transport in the mitochondrion and in modulating potentially toxic acyl-CoA levels in the mitochondrial matrix. There are no naturally occurring esterases available to reduce the accumulation of acyl-CoA but this process can be overcome by exogenous carnitine. We used a newborn rat model of perinatal hypoxia-ischemia to test the hypothesis that treatment with l-carnitine would reduce the neuropathologic injury resulting from hypoxia-ischemia in the developing brain. We found that treatment with l-carnitine during hypoxia-ischemia reduces neurologic injury in the immature rat after both a 7- and 28-d recovery period. We saw no neuroprotective effect when l-carnitine was administered after hypoxia-ischemia. Treatment with d-carnitine resulted in an increase in mortality during hypoxia-ischemia. Carnitine is easy to administer, has low toxicity, and is routinely used in neonates as well as children with epilepsy, cardiomyopathy, and inborn errors of metabolism. l-Carnitine merits further investigation as a treatment modality for the asphyxiated newborn or as prophylaxis for the at-risk fetus or newborn.

Shallow bedrock strength controls both landslide hazard and the rate and form of erosion, yet regional patterns in near‐surface mechanical properties are rarely known quantitatively due to the challenge in collecting in situmeasurements. Here we present seismic and geomechanical characterizations of the shallow subsurface across the central Himalayan Range in Nepal. By pairing widely distributed 1D shear wave velocity surveys and engineering outcrop descriptions per the Geological Strength Index classification system, we evaluate landscape‐scale patterns in near‐surface mechanical characteristics and their relation to environmental factors known to affect rock strength. We find that shallow bedrock strength is more dependent on the degree of chemical and physical weathering, rather than the mineral and textural differences between the metamorphic lithologies found in the central Himalaya. Furthermore, weathering varies systematically with topography. Bedrock ridge top sites are highly weathered and have S‐wave seismic velocities and shear strength characteristics that are more typical of soils, whereas sites near valley bottoms tend to be less weathered and characterized by high S‐wave velocities and shear strength estimates typical of rock. Weathering on hillslopes is significantly more variable, resulting in S‐wave velocities that range between the ridge and channel endmembers. We speculate that variability in the hillslope environment may be partly explained by the episodic nature of mass wasting, which clears away weathered material where landslide scars are recent. These results underscore the mechanical heterogeneity in the shallow subsurface and highlight the need to account for variable bedrock weathering when estimating strength parameters for regional landslide hazard analysis. Rock strength controls the occurrence of landslides and the relationship between topography and erosion, but it is rarely known in natural environments because the most common measurement techniques are designed for individual site characterization and they are time‐consuming to apply over broad spatial scales. In this paper, we apply a unique sampling strategy consisting of two field‐based measurement techniques that are relatively portable and quick to apply repeatedly, and provide rock strength information over the scale of an outcrop (tens of meters). We apply our approach to an area of central Nepal where rock strength estimates are particularly important to know due to the high landslide hazard in this region. Our results show that rock strength is strongly controlled by the degree of weathering (i.e., the breakdown of rock by chemical and physical processes), which varies widely in Nepal depending on the local climate and topographic characteristics. In particular, we find that weathering is systematically greater (and thus rock strength is lower) on ridges compared to valley bottoms. On hillslopes between ridges and valleys, both weathering and rock strength are highly variable and difficult to predict, highlighting the need to further investigate regional variability in rock strength for future landslide hazard assessment. We employ seismic surveys and geomechanical rockmass characterizations to investigate regional patterns in rock strengthNo single variable explains the observed patterns in near‐surface mechanical properties within this tectonically active terrainWeathering characteristics associated with ridge‐to‐channel topography contributes order‐of‐magnitude variations in near‐surface strength We employ seismic surveys and geomechanical rockmass characterizations to investigate regional patterns in rock strength No single variable explains the observed patterns in near‐surface mechanical properties within this tectonically active terrain Weathering characteristics associated with ridge‐to‐channel topography contributes order‐of‐magnitude variations in near‐surface strength

Contractional deformation is common along transform plate margins where plate motion is oblique to the plate boundary. While faults that accommodate this deformation are often inferred to be subsidiary to the main plate boundary fault, we typically lack direct geometric or kinematic information. Here we investigate the timing of faulting relative to changes in the orientation of the North American‐Pacific plate boundary. Coeval with development of an oblique plate boundary segment (i.e., the “Big Bend” of the San Andreas fault), active shortening is inferred to have initiated at ∼5 Ma in the Western Transverse Ranges (WTR). However, new low‐temperature thermochronometric data yield Miocene to Pleistocene apatite (U‐Th‐Sm)/He cooling ages and partially reset zircon (U‐Th)/He ages. Inverse thermal modeling indicate that reverse faulting initiated as early as 10 Ma, several million years prior to our current understanding of the timing of the Big Bend. Reverse faults in the WTR also propagate from west to east, toward the San Andreas Fault, rather than outwards from it. New and existing thermochronometry data delineate the WTR as the locus of rapid post‐Miocene exhumation, and demonstrate that similar exhumation is not present in the broader region surrounding the Big Bend. We posit that reverse faulting is localized in the WTR because of a weak underlying lithosphere and predates the more recent geometric anomaly of the restraining bend in the transform margin. Apatite and zircon helium thermochronometry data from the Western Transverse Ranges (WTR) yield late‐Miocene through Pleistocene cooling agesReverse faulting within the block initiated prior to, and propagates toward, the Big Bend restraining bend in the San Andreas faultRapid post‐late‐Miocene tectonic exhumation in the region surrounding the Big Bend is localized within the WTR Apatite and zircon helium thermochronometry data from the Western Transverse Ranges (WTR) yield late‐Miocene through Pleistocene cooling ages Reverse faulting within the block initiated prior to, and propagates toward, the Big Bend restraining bend in the San Andreas fault Rapid post‐late‐Miocene tectonic exhumation in the region surrounding the Big Bend is localized within the WTR

There is a possibility of using rhenium and its alloys as a material for high-stable and high-temperature thin-film resistors as shown in this article.

Rock mass strength is recognized as an important control on landscape morphology and evolution. However, the controls on rock strength in mountainous topography remain poorly characterized, in part because strength remains challenging to quantify at spatial scales relevant to geomorphology. Here we quantify the mechanical properties of rock masses using subsurface S‐wave velocities, Schmidt hammer hardness values, and Geological Strength Index (GSI) observations. We produce shallow depth profiles of rock mass shear strength using intact rock hardness as measured from a Schmidt hammer, and assessment of the structure and surface conditions of fractures using GSI. We apply these techniques to the Western Transverse Ranges, southern California, USA, where gradients in stratigraphic age and erosion rate allow us to evaluate our methodology. We resolve strength differences of 200 kPa to ∼5 MPa that appear to be related to diagenetic changes associated with the maximum burial depth of young clastic sedimentary rocks. For rocks of the same lithologic type, stratigraphic age, and inferred burial histories, we resolve smaller differences in strength (300 kPa–1.5 MPa) that appear to be positively correlated with mean erosion rates. We suggest that the increase in strength with increasing erosion rate reflects decreased residence time in the weathering zone for ranges experiencing faster fault slip rates. These findings demonstrate up to an order of magnitude variability in strength with respect to burial, erosion, and time for lithologically similar rocks. As such, lithology alone is unlikely to adequately capture the role of rock strength in landscape evolution. We present a novel approach to quantify near‐surface rock mass strength on depth profiles from surface and subsurface measurementsThe rock mass strength of sandstone units increases with increasing maximum burial depth prior to exhumationRock strength and erosion rate are positively correlated, which we suggest is driven by critical zone residence time and weathering extent We present a novel approach to quantify near‐surface rock mass strength on depth profiles from surface and subsurface measurements The rock mass strength of sandstone units increases with increasing maximum burial depth prior to exhumation Rock strength and erosion rate are positively correlated, which we suggest is driven by critical zone residence time and weathering extent

The timing of crustal shortening and strike‐slip faulting along the East Kunlun Shan provides insight into the history of surface uplift and may constrain the time at which the Tibetan Plateau reached high elevations. We investigate a series of extensional basins and restraining bends along the Xidatan strand of the Kunlun strike‐slip fault, which provide an ideal setting to unravel the tectonic history of the northern plateau margin. We present new apatite (U‐Th)/He, apatite fission track, and zircon (U‐Th)/He ages and QTQt thermal modeling, 40Ar/39Ar fault gouge dating, and structural mapping from the central East Kunlun Shan. Our data suggest that the East Kunlun Shan experienced slow to negligible exhumation until late Cretaceous time, followed by an increase in rate by 65–50 Ma. Along with a ~47 Ma fault gouge age, we posit that the Paleocene–early Eocene was a time of crustal shortening along the northern plateau. Rapid exhumation along transpressional portions of the Xidatan fault initiated by 23–20 Ma, which we interpret as the local onset of strike‐slip faulting. An early Miocene transition from north‐south crustal shortening to left‐lateral shear along the East Kunlun Shan, the onset of normal and strike‐slip faulting in central and southern Tibet by 18 Ma, and lower crustal flow in eastern Tibet by 13 Ma suggest the establishment of orogen‐wide east‐west oriented extension and extrusion by the middle Miocene. The plateau‐wide shift in stress accommodation implies that high gravitational potential energy, and likely high elevation, was attained by the middle Miocene. The central East Kunlun Shan is an ideal setting to investigate the tectonic evolution of northern Tibet and plateau‐wide geodynamic driversThe central East Kunlun Shan experienced crustal shortening from Paleocene–Oligocene time followed by a 23–20 Ma onset of strike‐slip faultingThe plateau‐wide mid‐Miocene onset of strike‐slip and normal faulting signals the attainment of high GPE and elevation

Rock strength is a fundamental property of earth materials that influences the morphology of landscapes and modulates feedbacks between surface processes, tectonics, and climate. However, rock strength remains challenging to quantify over the broad spatial scales necessary for geomorphic investigations. Consequently, the factors that control rock strength in the near‐surface environment (i.e., the critical zone) remain poorly understood. Here we quantify near‐surface rock strength on a regional scale by exploiting two hillslope‐stability models, which explicitly relate the balance of forces within a hillslope to Mohr‐Coulomb strength parameters. We first use the Culmann finite‐slope stability model to back‐calculate static rock strength with high‐density measurements of ridge‐to‐channel hillslope height and gradient. Second, we invert the Newmark infinite‐slope stability model for strength using an earthquake peak ground acceleration model and coseismic landslide inventory. We apply these two model approaches to a recently inverted sedimentary basin in the eastern Topatopa Mountains of southern California, USA, where a tectonic gradient has exposed stratigraphic units with variable burial histories. Results show similar trends in strength with respect to stratigraphic position and have comparable strength estimates to the lowest values of published direct‐shear test data. Cohesion estimates are low, with Culmann results ranging from 3 to 60 kPa and Newmark results from 6 to 30 kPa, while friction angle estimates range from 24° to 44° from the Culmann model. We find that maximum burial depth exerts the strongest control on the strength of these young sedimentary rocks, likely through diagenetic changes in porosity, cementation, and ultimately, lithification. We quantify hillslope‐scale, near‐surface rock strength on a regional scale using the Culmann and Newmark hillslope‐stability modelsStrength estimates are generally low, with cohesion model predictions less than 60 kPa for friction angle predictions of 24° to 44°The cohesion of young sedimentary rocks in the shallow subsurface increases with increasing maximum burial depth