Compacting Plastic-Bonded Explosive Molding Powders to Dense Solids

Dense solid high explosives are made by compacting plastic-bonded explosive molding powders with high pressures and temperatures for extended periods of time. The density is influenced by manufacturing processes of the powders, compaction temperature, the magnitude of compaction pressure, pressure duration, and number of repeated applications of pressure. The internal density variation of compacted explosives depends on method of compaction and the material being compacted

Solid explosive plane-wave lenses pressed-to-shape with dies

Solid-explosive plane-wave lenses 1", 2" and 4¼" in diameter have been mass-produced from components pressed-to-shape with aluminum dies. The method used to calculate the contour between the solid plane-wave lens components pressed-to-shape with the dies is explained. The steps taken to press, machine, and assemble the lenses are described. The method of testing the lenses, the results of those tests, and the corrections to the dies are reviewed. The work on the ½", 8", and 12" diameter lenses is also discussed

Precise and Accurate Density Determination of Explosives Using Hydrostatic Weighing

Precise and accurate density determination requires weight measurements in air and water using sufficiently precise analytical balances, knowledge of the densities of air and water, knowledge of thermal expansions, availability of a density standard, and a method to estimate the time to achieve thermal equilibrium with water. Density distributions in pressed explosives are inferred from the densities of elements from a central slice

Variability in the anterior extralaryngeal branch of the recurrent laryngeal nerve: clinical implications

Background: This study aimed to identify the anterior and posterior extralaryngeal branches (AELB, PELB) of the recurrent laryngeal nerve (RLN), measure these branches when present, and determine relationships between gender, sidedness and neck length. Materials and methods: Dissection was completed to level of the thyroid on 45 cadavers. The course of the RLN was then traced superiorly from its entry into the neck. Careful reflection of the thyroid and dissection of the lateral thyroid ligament permitted visualisation of the full course of the nerve. If extralaryngeal branching (ELB) was present, measurements were taken from the point of bifurcation of the RLN to the point of laryngeal entry through the cricothyroid membrane. Neck measurements, from the spinous process of C7 to the superior nuchal line, were taken. Gender of the specimen was noted. Data was analysed in SPSS. Results: Extralaryngeal branching was found in 77.78% of our sample, 77.14% on the left and 54.29% on the right. A significant difference was found between AELB length on the left and right, indicating that the left branch will be longer than the right when present. A significant difference in neck length between those with and without ELB was also found, indicating that people with longer necks more often display ELB. Neither neck length and AELB length, nor gender and AELB length were strongly correlated in this sample. Conclusions: Extralaryngeal branching can occur in all populations, but there are definite trends in its incidence and length. Surgeons should be aware of these trends before operating on patients

The spectrum of gastric cancer as seen in a large quaternary hospital in KwaZulu-Natal, South Africa

Background. Gastric cancer (GC) is the fifth most commonly diagnosed cancer in the world, with the third-highest associated mortality. It has a varying geographical, ethnic and socioeconomic distribution.Objective. To assess the presentation and management of GC in the Durban metropolitan area, South Africa.Methods. A retrospective review of 131 patients treated at the quaternary Inkosi Albert Luthuli Central Hospital in Durban from 2009 to 2014 was performed.Results. The 131 patients were predominantly black African (n=59, 45.0%) and Indian (n=63, 48.1%). Gender was evenly distributed, with 72 males (55.0%) and 59 females (45.0%). The average age of the patients was 60 years (standard deviation 13.3). More than 70% were in advanced stages of cancer and were treated conservatively. There was no significant relationship between body mass index (BMI) and the position of the tumour (p=0.175). Creatinine and albumin levels differed significantly between the genders (p<0.001 and p=0.01, respectively).Conclusions. GC appears to have a disproportionately high prevalence among Indians in Durban, and the prevalence of GC appears to be slightly higher among males. Both these observations may simply reflect referral patterns and warrant further investigation. More than 70% of patients presented with advanced-stage disease, and anaemia was common. No relationship was found between BMI and the location of the tumour, although most of the cancers were in the body and distal part of the stomach

Coral recruitment is impacted by the presence of a sponge community

© 2019 Peng Luo et al., published by De Gruyter, Berlin/Boston. C23H13NO4, monoclinic, P21/n (no. 14), a = 11.6537(6) Å, b = 5.1315(2) Å, c = 26.8047(13) Å, β = 96.266(3)°, V = 1593.4(13) Å3, Z = 4, Rgt(F) = 0.0531, wRref(F2) = 0.1432, T = 90.0(5) K

Development of a model for marburgvirus based on severe-combined immunodeficiency mice

The filoviruses, Ebola (EBOV) and Marburg (MARV), cause a lethal hemorrhagic fever. Human isolates of MARV are not lethal to immmunocompetent adult mice and, to date, there are no reports of a mouse-adapted MARV model. Previously, a uniformly lethal EBOV-Zaire mouse-adapted virus was developed by performing 9 sequential passages in progressively older mice (suckling to adult). Evaluation of this model identified many similarities between infection in mice and nonhuman primates, including viral tropism for antigen-presenting cells, high viral titers in the spleen and liver, and an equivalent mean time to death. Existence of the EBOV mouse model has increased our understanding of host responses to filovirus infections and likely has accelerated the development of countermeasures, as it is one of the only hemorrhagic fever viruses that has multiple candidate vaccines and therapeutics. Here, we demonstrate that serially passaging liver homogenates from MARV-infected severe combined immunodeficient (scid) mice was highly successful in reducing the time to death in scid mice from 50–70 days to 7–10 days after MARV-Ci67, -Musoke, or -Ravn challenge. We performed serial sampling studies to characterize the pathology of these scid mouse-adapted MARV strains. These scid mouse-adapted MARV models appear to have many similar properties as the MARV models previously developed in guinea pigs and nonhuman primates. Also, as shown here, the scid-adapted MARV mouse models can be used to evaluate the efficacy of candidate antiviral therapeutic molecules, such as phosphorodiamidate morpholino oligomers or antibodies

The spectrum of gastric cancer as seen in a large quaternary hospital in KwaZulu-Natal, South Africa

Background. Gastric cancer (GC) is the fifth most commonly diagnosed cancer in the world, with the third-highest associated mortality. It has a varying geographical, ethnic and socioeconomic distribution.Objective. To assess the presentation and management of GC in the Durban metropolitan area, South Africa.Methods. A retrospective review of 131 patients treated at the quaternary Inkosi Albert Luthuli Central Hospital in Durban from 2009 to 2014 was performed.Results. The 131 patients were predominantly black African (n=59, 45.0%) and Indian (n=63, 48.1%). Gender was evenly distributed, with 72 males (55.0%) and 59 females (45.0%). The average age of the patients was 60 years (standard deviation 13.3). More than 70% were in advanced stages of cancer and were treated conservatively. There was no significant relationship between body mass index (BMI) and the position of the tumour (p=0.175). Creatinine and albumin levels differed significantly between the genders (p<0.001 and p=0.01, respectively).Conclusions. GC appears to have a disproportionately high prevalence among Indians in Durban, and the prevalence of GC appears to be slightly higher among males. Both these observations may simply reflect referral patterns and warrant further investigation. More than 70% of patients presented with advanced-stage disease, and anaemia was common. No relationship was found between BMI and the location of the tumour, although most of the cancers were in the body and distal part of the stomach

Universal criterion for the breakup of invariant tori in dissipative systems

The transition from quasiperiodicity to chaos is studied in a two-dimensional dissipative map with the inverse golden mean rotation number. On the basis of a decimation scheme, it is argued that the (minimal) slope of the critical iterated circle map is proportional to the effective Jacobian determinant. Approaching the zero-Jacobian-determinant limit, the factor of proportion becomes a universal constant. Numerical investigation on the dissipative standard map suggests that this universal number could become observable in experiments. The decimation technique introduced in this paper is readily applicable also to the discrete quasiperiodic Schrodinger equation.Comment: 13 page