This paper is a review of the observational, experimental, theoretical, and numerical studies of mesoscale shallow convection (MSC) in the atmosphere. Typically, MSC is 1 to 2 km deep, has a horizontal length scale of a few to a few tens of kilometers, and takes distinctive planforms: linear and hexagonal. The former is called a cloud street, roll, or band, while the latter is called mesoscale cellular convection (MCC), comprising three‐dimensional cells. MSC is characterized by its shape, horizontal extent, convective depth, and aspect ratio. The latter is the ratio of the horizontal extent to that in the vertical. For cells the horizontal extent is their diameter, whereas for rolls it is their spacing. Rolls usually align along or at angles of up to 10° from the mean horizontal wind of the convective layer, with lengths from 20 to 200 km, widths from 2 to 10 km, and convective depths from 2 to 3 km. The typical value of aspect ratio ranges from 2 to 20. Rolls may occur over both water surface and land surfaces. Mesoscale convective cells may be divided into two types: open and closed. Open‐cell circulation has downward motion and clear sky in the cell center, surrounded by cloud associated with upward motion. Closed cells have the opposite circulation. Both types of cell have diameters ranging from 10 to 40 km and aspect ratios of 5 to 50, and both occur in a convective layer with a depth of about 1 to 3 km. Both the magnitude and direction of horizontal wind in the convective layer change little with height. MSC results from a complex and incompletely understood mix of processes. These processes are outlined, and their interplay is examined through a review of theoretical and laboratory analyses and numerical modeling of MSC.

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A combination of observations and a numerical model revealed the meso-scale structure of the near-surface atmospheric conditions over the Persian Gulf. Low-level winds were dominated by a single, coherent, perennial land-sea breeze circulation (LSBC) that varied seasonally and diurnally. In summer the sea breeze was deeper and wider than in winter. At night the core of the LSBC over the Gulf was confluent with uplift, whereas in daytime it was difluent with subsidence. Sensitivity tests with the model revealed the influence on the LSBC of the land-sea distribution, orography and the ambient wind. The latter resulted in different conditions over the north, east, south and west coasts. Over the north coast, where the opposing ambient wind created a sea breeze front, landward penetration was very limited; over the south coast it was over 250 km. The thermal effect of the Iranian mountains accentuated the depth and penetration, landward and seaward, of the LSBC, thus influencing the duration of the land and sea breezes over the east coast. From spring to autumn the marine boundary layer over the Gulf was shallow, cool, moist and stable, with strong vertical gradients of temperature and humidity at its top. Its depth increased in the ambient flow from northwest to southeast and also, in daytime, from west to east, because of different magnitudes of the subsidence in the sea breeze circulation over the west and east coasts.

Eight fence designs with and without electrification were tested for their ability to stop feral pigs crossing from one paddock to another.Fences of 8:80: 15 hingejoints were pig-proof, whereas fences of 6:70:30 hingejoint or plain wires allowed some pigs to cross. Electrification of the fences significantly reduced the frequency of pig movement through fences to as little as 6.3% of test pigs. The behaviour offeral pigs relative to the fences and their implications are described.

Invasive meningococcal disease caused by Neisseria meningitidis presents a significant public health concern. Meningococcal disease is rare but potentially fatal within 24 hours of onset of illness, and survivors may experience permanent sequelae. This review presents the epidemiology, incidence, and outbreak data for invasive meningococcal disease in the United States since 1970, and it highlights recent changes in vaccine recommendations to prevent meningococcal disease. Relevant publications were obtained by database searches for articles published between January 1970 and July 2015. The incidence of meningococcal disease has decreased in the United States since 1970, but serogroup B meningococcal disease is responsible for an increasing proportion of disease burden in young adults. Recent serogroup B outbreaks on college campuses warrant broader age-based recommendations for meningococcal group B vaccines, similar to the currently recommended quadrivalent vaccine that protects against serogroups A, C, W, and Y. After the recent approval of two serogroup B vaccines, the Advisory Committee on Immunization Practices first updated its recommendations for routine meningococcal vaccination to cover at-risk populations, including those at risk during serogroup B outbreaks, and later it issued a recommendation for those aged 16-23 years. Meningococcal disease outbreaks remain challenging to predict, making the optimal disease management strategy one of prevention through vaccination rather than containment. How the epidemiology of serogroup B disease and prevention of outbreaks will be affected by the new category B recommendation for serogroup B vaccines remains to be seen.