Crew Half Duty Day: Today was a half duty day for the crew. Following Cygnus berth tomorrow, they will work Saturday to transfer cargo from Cygnus to the ISS.

Fluids Integrated Rack (FIR)/Light Microscopy Module (LMM)/Biophysics-6 experiment start: As a followup to the discovery of the plate with damaged sample capillary(s) on Monday, today the crew removed another LMM/Biophysics-6 (Bio-6) plate from MELFI and allowed it to thaw. Following a good inspection, it was inserted in the LMM to begin the experiment. LMM/Bio-6, more formally known as Growth Rate Dispersion as a Predictive Indicator for Biological Crystal Samples Where Quality Can Be Improved with Microgravity Growth, studies ground-based predictions of which crystals benefit from crystallization in microgravity, where Earth’s gravity does not interfere with their formation. The plate installed contains samples of Geranylgeranyl pyrophosphate synthase (GGPPS) which is a protein produced in osteoporosis, multiple myeloma, and Paget’s disease. Observing crystallized proteins via X-ray crystallography on the ground allows scientists to determine how they are built, which can explain how they work or how other molecules, such as drugs, might interact with them.

Mass Measurement Device (MMD) Setup: The crew gathered the hardware and set up the MMD in the designated module and seat track mounting location. Poweron, thermal stabilization and hardware calibration will be performed to prepare MMD for Rodent Research-12 support. The Mass MMD provides a system to quantify the mass of objects, including live animal specimens, in the microgravity environment aboard the International Space Station. It is capable of measuring mass in the range of 1 to 100 grams with accuracies that exceed 0.1 grams.

Rodent Research-12: The crew performed the Habitat installation and participated in a crew conference to discuss RR-12 and transfers of the mice. The actual mouse transfer from NG-11 to ISS occurs Saturday. RR12 has 2 specific aims: 1) To determine the impact of the spaceflight environment on primary and secondary antibody responses. 2) Establish that adjuvants that function through Tlr9 receptors are effective during spaceflight. Rodent Research-12, Tetanus Antibody Response by B cells in Space (TARBIS), examines the effects of spaceflight on the function of antibody production and immune memory. Spaceflight is known to have a dramatic influence on immune response, but there is little research on its effect following an actual challenge to the body’s immune system. Using a mouse model makes this possible, as the mouse immune system closely parallels that of humans.

Cygnus Arrival Preparations: In preparation for tomorrow’s planned Cygnus berthing, the crew completed the following:

Installed the Centerline Berthing Camera System (CBCS) at Node 1 Nadir and performed a video system checkout with the ground. This activity is to support Common Berthing Mechanism (CBM) mating operations.

Relocated the Portable Computer System (PCS) from the Airlock to the Cupola to provide command redundancy during Cygnus capture operations.

Completed Task List Activities:

Straightened ARED upper stop cable

“Pics In Space” video recording

“Wayfinding” video recording

Ground Activities:

All activities are complete unless otherwise noted.



Rodent Research preparations

CBCS install/checkout

Friday, 4/19:

Payloads:



ISS Experience

Repository

RR Habitat install

Standard Measures

SUBSA sample exchange

Two-phase flow 2

Systems:

NG-11 berth/ingress/cargo transfer

Saturday, 4/20:

Payloads:

Cold Stowage transfers

Nanoracks platform-1 (install mod 78 and remove mod 77)

Repository

Rodent Research-12 transfers

Tangolab-1 card cube ops

Systems:

Cygnus cargo transfer

Cygnus OBT emergency procedure review

Sunday, 4/21:

Payloads:



Repository

Standard Measures

Systems:

Crew off duty

Today’s Planned Activities:

All activities are complete unless otherwise noted.

