The Effect of Freezing Conditions on Xylem Diameter of Malosma laurina and Umbellularia californica in the Santa Monica Mountains

Temperature variations in the Santa Monica Mountains are drastic at times, which may be affecting the local plants. To determine the repercussions of these variations in temperature, we measured the xylem diameters of freezing and non-freezing Malosma laurina and Umbellularia californica. U. californica was chosen because it has a large xylem diameter, yet is known to survive freezing conditions. We thought that this plant could provide the most significant results to prove or disprove our hypothesis. M. laurina was chosen because it is abundant in the Santa Monica Mountains and has different physical dimensions than U. californica. Smaller xylem diameters may affect water transport , possibly resulting in physically smaller plant sizes. Natural selection may be acting on these species in the Santa Monica Mountains, eliminating plants with larger xylem diameters in freezing areas. We hypothesize that M. laurina and U. californica in freezing zones will have smaller xylem diameters compared to those in non-freezing zones. We collected samples of M. laurina and U. californica from freezing and non-freezing sites located in Tapia Park and Solstice park in the Santa Monica Mountains and on Pepperdine University’s Malibu Campus. We then prepared slides of the plants’ stems and measured the diameters of the xylems. Using Kaleidagraph, we statistically analyzed our data and found the average values for each plant; freezing M. laurina had an average xylem diameter of 33.3 μm, non-freezing M. laurina had an average xylem diameter of 48.7 μm, freezing U. californica had an average xylem diameter of 33.4 μm, and non-freezing U. californica had an average xylem diameter of 53.8 μm. These results indicate significance as revealed by a p value \u3c0.05

Amenorrhea and pituitary human chorionic gonadotrophin production in a 38-year-old presenting as pregnancy of unknown location: case report and review of literature

Background: Amenorrhea and extraplacental production of serum human chorionic gonadotropin (hCG), particularly in young women, can mimic a pregnancy of unknown location. Elevated serum hCG in the absence of pregnancy can pose a diagnostic dilemma and has led to potentially harmful and unwarranted interventions including chemotherapeutic agents like methotrexate or have led to delay in necessary medical interventions in women. We report a case to demonstrate that amenorrhea and extraplacental human chorionic gonadotropin (hCG) production in young women can mimic a pregnancy of unknown location. Furthermore, we performed a critical review of literature on pituitary hCG production. Case: A 38-year-old woman with a diagnosis of Silver-Russell syndrome, a unicornuate uterus, history of right oophorectomy for a benign serous cystadenoma and a desire for pregnancy presenting with a provisional diagnosis of pregnancy of unknown location.After performing a thorough review of history, physical examination, ultrasound exams, and a review of hormone analysis [including hCG, Tumor markers, Follicle-stimulating hormone (FSH), Luteinizing hormone (LH), Anti-Mullerian Hormone (AMH), Estradiol (E2) levels], we confirmed the diagnosis of premature ovarian insufficiency and pituitary hCG production. Conclusions: In women, serum levels of hCG may increase with age, and are not always an indicator of pregnancy. Therefore, it is imperative to interpret false-positive test results and rule out the extraplacental production of hCG. This will help prevent unnecessary surgical procedures and treatment, including chemotherapy

The Effect of Water Deficit on Photosynthetic Properties of Salvia leucophylla

California has been in a severe drought in recent years due to anthropogenic warming, and it has had a major effect on chemical and physical properties of native plants. Salvia leucophylla, a common plant in Southern California, has evolved an adaptation to water stress through losing its leaves, known as a drought deciduous plant. Considering the increase of CO2 in the atmosphere, it is absolutely essential for leaves to retain their ability to photosynthesize to maintain the health of the environment through CO2 sequestration. The objective of this experiment was to see how drought levels affect the physical and chemical properties of Salvia leucophylla, also known as purple sage. Our prediction is that drought conditions will compromise the plant’s photosynthetic rate and stomatal conductance. We investigated this issue by creating three treatments: a control watered every other day, and two manipulated groups watered weekly and none at all. After two weeks, we measured the photosynthetic rate, stomatal conductance, ETR, qN and qP, Fv’/Fm’, and leaf temperature. Our results showed that there was a significant decrease of photosynthetic rate (