The InSight HP3 Penetrator (Mole) on Mars: Soil Properties Derived from the Penetration Attempts and Related Activities.

The NASA InSight Lander on Mars includes the Heat Flow and Physical Properties Package HP3 to measure the surface heat flow of the planet. The package uses temperature sensors that would have been brought to the target depth of 3-5 m by a small penetrator, nicknamed the mole. The mole requiring friction on its hull to balance remaining recoil from its hammer mechanism did not penetrate to the targeted depth. Instead, by precessing about a point midway along its hull, it carved a 7 cm deep and 5-6 cm wide pit and reached a depth of initially 31 cm. The root cause of the failure - as was determined through an extensive, almost two years long campaign - was a lack of friction in an unexpectedly thick cohesive duricrust. During the campaign - described in detail in this paper - the mole penetrated further aided by friction applied using the scoop at the end of the robotic Instrument Deployment Arm and by direct support by the latter. The mole tip finally reached a depth of about 37 cm, bringing the mole back-end 1-2 cm below the surface. It reversed its downward motion twice during attempts to provide friction through pressure on the regolith instead of directly with the scoop to the mole hull. The penetration record of the mole was used to infer mechanical soil parameters such as the penetration resistance of the duricrust of 0.3-0.7 MPa and a penetration resistance of a deeper layer ( > 30 cm depth) of 4.9 ± 0.4 MPa . Using the mole's thermal sensors, thermal conductivity and diffusivity were measured. Applying cone penetration theory, the resistance of the duricrust was used to estimate a cohesion of the latter of 2-15 kPa depending on the internal friction angle of the duricrust. Pushing the scoop with its blade into the surface and chopping off a piece of duricrust provided another estimate of the cohesion of 5.8 kPa. The hammerings of the mole were recorded by the seismometer SEIS and the signals were used to derive P-wave and S-wave velocities representative of the topmost tens of cm of the regolith. Together with the density provided by a thermal conductivity and diffusivity measurement using the mole's thermal sensors, the elastic moduli were calculated from the seismic velocities. Using empirical correlations from terrestrial soil studies between the shear modulus and cohesion, the previous cohesion estimates were found to be consistent with the elastic moduli. The combined data were used to derive a model of the regolith that has an about 20 cm thick duricrust underneath a 1 cm thick unconsolidated layer of sand mixed with dust and above another 10 cm of unconsolidated sand. Underneath the latter, a layer more resistant to penetration and possibly containing debris from a small impact crater is inferred. The thermal conductivity increases from 14 mW/m K to 34 mW/m K through the 1 cm sand/dust layer, keeps the latter value in the duricrust and the sand layer underneath and then increases to 64 mW/m K in the sand/gravel layer below. Supplementary Information: The online version contains supplementary material available at 10.1007/s11214-022-00941-z.

Synthesis and Workability Behavior of Cu-X wt.% TiC (x = 0, 4, 8, and 12) Powder Metallurgy Composites.

In this work, copper (Cu) matrix composite reinforced with titanium carbide (TiC) was fabricated by powder metallurgy (PM) method with the varying TiC content from 0% to 12% by weight in the step of 4%. The required weight percentage of powders was milled in an indigenously developed ball milling setup. Green compacts were made using a computer-controlled hydraulic press (400 kN) and sintered in a muffle furnace at a temperature of 950°C. Scanning electron microscope (SEM) was used to analyze the distribution of TiC particles in Cu matrix in as-sintered conditions. X-ray diffraction (XRD) analysis resulted in the existence of respective phases in the produced composites. The structural characteristics such as stress, strain, dislocation density, and grain size of the milled composites were evaluated. Cold upsetting was conducted for the sintered composites at room temperature to evaluate the axial (σ z ), hoop (σ Ó© ), hydrostatic (σ m ), and effective (σ eff ) true stresses. These stresses were analyzed against true axial strain (ε z ). Results showed that the increase in the inclusion of weight percentage of TiC into the Cu matrix increases density, hardness, (σ z ), (σ Ó© ), (σ m ), (σ eff ), and stress ratio parameters such as (σ z /σ eff ), (σ θ /σ eff ), (σ m /σ eff ), and (σ z /σ θ ) of the composites.

Ovarian reserve after salpingectomy: a systematic review and meta-analysis.

INTRODUCTION: Although there has been a growing concern over the possible damaging effect of salpingectomy on ovarian reserve, this issue remains uncertain. The purpose of this meta-analysis was to test the hypothesis that salpingectomy may compromise ovarian reserve. MATERIAL AND METHODS: A detailed search was conducted using MEDLINE, Embase, Dynamed Plus, ScienceDirect, TRIP database and the Cochrane Library from January 2000 to November 2016. All cohort, cross-sectional and randomized controlled studies investigating changes in circulating anti-Müllerian hormone (AMH) after salpingectomy were considered. Thirty-seven studies were identified, of which eight were eligible. Data were extracted and entered into RevMan software for calculation of the weighted mean difference (WMD) and 95% CI. Two groups of studies were analyzed separately: group 1 (six studies, n = 464) comparing data before and after salpingectomy and group 2 (two studies) comparing data in women who have undergone salpingectomy (n = 169) vs. healthy controls (n = 154). RESULTS: Pooled results of group 1 studies showed no statistically significant change in serum AMH concentration after salpingectomy (WMD, -0.10 ng/mL; 95% CI -0.19 to 0.00, I2 = 0%). Similarly, meta-analysis of group 2 showed no statistically significant difference in serum AMH concentration between salpingectomy group and controls (WMD, -0.11 ng/mL; 95% CI -0.37 to 0.14, I2 = 77%). Subgroup analyses based on laterality of surgery, type of AMH kit and participants' age (<40 years) still showed no statistically significant changes in circulating AMH. CONCLUSION: Salpingectomy does not seem to compromise ovarian reserve in the short-term. However, the long-term effect of salpingectomy on ovarian reserve remains uncertain.

Virulence loss and amastigote transformation failure determine host cell responses to Leishmania mexicana.

The effect of alterations in virulence and transformation by long-term in vitro culture of Leishmania mexicana promastigotes on infectivity and immune responses was investigated. Fresh parasite cultures harvested from Balb/c mice were passaged 20 times in vitro. Infectivity was decreased and was completely avirulent after 20 passages. The qPCR results showed a down-regulation of GP63, LPG2, CPC, CPB2, CPB2.8, CHT1, LACK and LDCEN3 genes after passage seven concomitant with a reduced and absence of infectivity by passages seven and 20, respectively. Parasites at passages one and 20 are referred to as virulent and avirulent, respectively. The growth of avirulent and virulent parasite was affected by conditioned media derived from macrophages or monocytes infected with parasites for 2 h. Giemsa staining showed the failure of avirulent but not virulent parasites to transform to the amastigote stage in infected host cells with both virulent and avirulent modulating the expression of CCL-22, Tgad51, Cox2, IL-1, IL-10, TGF-ß, TNF-α, Rab7, Rab9 and A2 genes; virulent but not avirulent L. mexicana significantly up-regulated Th2-associated cytokines, but down-regulated Rab7 and Rab9 gene expression. In conclusion, a model for L. mexicana is reported, which is of potential value in studying host-parasite interaction.

Custom made alar stents for nostril stenosis: a 24-month evaluation.

Nostril stenosis is an uncommon deformity and its aetiology is variable. The shape alteration and nostril asymmetry may have negative aesthetic and functional effects on nostril stenosis patients. Five patients were included in this study and followed up for 24 months; four of these had congenital nostril stenosis and one had an acquired deformity. Alar stent dilators were constructed from measured diameter of the affected nostril/s. The congenital nostril stenosis patients initially received a customised chairside soft nasal dilator (CCSND), which were later replaced with a customised laboratory rigid nasal dilators (CLRND). Treatment outcomes were evaluated using a questionnaire and a visual analogue scale to assess improvements in nostril breathing, comfort, appearance and satisfaction of the treatment provided by both types of dilators. There was improvement in nostril diameter with an average expansion of 7mm and this was stable at the desired diameter. The overall number of stents used to expand the tissues to the desired dimension ranged from 3 to 8 stents. Alar stent therapy is a conservative method to expand nostril tissues and has successfully maintained the nostril diameter for both acquired and congenital stenosis. This improvement in all parameters and the patients' satisfaction would make the custom-made nostril dilator in particular the CLRND a satisfactory treatment modality for congenital and acquired nostril stenosis.

First outbreak of dengue hemorrhagic fever, Bangladesh.

During the first countrywide outbreak of dengue hemorrhagic fever in Bangladesh, we conducted surveillance for dengue at a hospital in Dhaka. Of 176 patients, primarily adults, found positive for dengue, 60.2% had dengue fever, 39.2% dengue hemorrhagic fever, and 0.6% dengue shock syndrome. The Dengue virus 3 serotype was detected in eight patients.

Camel collision as a major cause of low cervical spinal cord injury.

One hundred and forty patients with low cervical spinal cord injuries, who were admitted to the Riyadh Armed Forces Hospital over the past 10 years were reviewed. Motor vehicle accidents constituted 119 (85%) of the patients. Camel collisions were a major cause of vehicle accidents 39 (33%), after rollover accidents 70 (59%), and much more than head on collisions 9 (7.5%). Male to female ratio was 14:1 with a mean age of 32 years. Camel collision although a commonly observed cause of motor vehicle accidents in the Middle East has not been mentioned in the literature before. The mechanism of injury is not much different, but the exact description of the accident and sustaining injury is interesting because it leads to localised damage to the neck without major body trauma and mortality.