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We present an evaluation of systematic effects associated with a continuously rotating, ambient-temperature half-wave plate (HWP) based on two seasons of data from the Atacama B-Mode Search (ABS) experiment located in the Atacama Desert of Chile. The ABS experiment is a microwave telescope sensitive at 145 GHz. Here we present our in-field evaluation of celestial (Cosmic Microwave Background (CMB) plus galactic foreground) temperature-to-polarization leakage. We decompose the leakage into scalar, dipole, and quadrupole leakage terms. We report a scalar leakage of ∼0.01%, consistent with model expectations and an order of magnitude smaller than other CMB experiments have been reported. No significant dipole or quadrupole terms are detected; we constrain each to be <0.07% (95% confidence), limited by statistical uncertainty in our measurement. Dipole and quadrupole leakage at this level lead to systematic error on r ≲ 0.01 before any mitigation due to scan cross-linking or boresight rotation. The measured scalar leakage and the theoretical level of dipole and quadrupole leakage produce systematic error of r < 0.001 for the ABS survey and focal-plane layout before any data correction such as so-called deprojection. This demonstrates that ABS achieves significant beam systematic error mitigation from its HWP and shows the promise of continuously rotating HWPs for future experiments.

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We evaluate the modulation of cosmic microwave background polarization using a rapidly rotating, half-wave plate (HWP) on the Atacama B-Mode Search. After demodulating the time-ordered-data (TOD), we find a significant reduction of atmospheric fluctuations. The demodulated TOD is stable on time scales of 500-1000 s, corresponding to frequencies of 1-2 mHz. This facilitates recovery of cosmological information at large angular scales, which are typically available only from balloon-borne or satellite experiments. This technique also achieves a sensitive measurement of celestial polarization without differencing the TOD of paired detectors sensitive to two orthogonal linear polarizations. This is the first demonstration of the ability to remove atmospheric contamination at these levels from a ground-based platform using a rapidly rotating HWP.

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The increasing scale of cryogenic detector arrays for submillimeter and millimeter wavelength astrophysics has led to the need for large aperture, high index of refraction, low loss, cryogenic refracting optics. Silicon with n=3.4, low loss, and high thermal conductivity is a nearly optimal material for these purposes but requires an antireflection (AR) coating with broad bandwidth, low loss, low reflectance, and a matched coefficient of thermal expansion. We present an AR coating for curved silicon optics comprised of subwavelength features cut into the lens surface with a custom three-axis silicon dicing saw. These features constitute a metamaterial that behaves as a simple dielectric coating. We have fabricated silicon lenses as large as 33.4 cm in diameter with micromachined layers optimized for use between 125 and 165 GHz. Our design reduces average reflections to a few tenths of a percent for angles of incidence up to 30° with low cross polarization. We describe the design, tolerance, manufacture, and measurements of these coatings and present measurements of the optical properties of silicon at millimeter wavelengths at cryogenic and room temperatures. This coating and lens fabrication approach is applicable from centimeter to submillimeter wavelengths and can be used to fabricate coatings with greater than octave bandwidth.

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Intestinal volvulus was recognized as the cause of death in 18 cetaceans, including 8 species of toothed whales (suborder Odontoceti). Cases originated from 11 institutions from around the world and included both captive (n = 9) and free-ranging (n = 9) animals. When the clinical history was available (n = 9), animals consistently demonstrated acute dullness 1 to 5 days prior to death. In 3 of these animals (33%), there was a history of chronic gastrointestinal illness. The pathological findings were similar to those described in other animal species and humans, and consisted of intestinal volvulus and a well-demarcated segment of distended, congested, and edematous intestine with gas and bloody fluid contents. Associated lesions included congested and edematous mesentery and mesenteric lymph nodes, and often serofibrinous or hemorrhagic abdominal effusion. The volvulus involved the cranial part of the intestines in 85% (11 of 13). Potential predisposing causes were recognized in most cases (13 of 18, 72%) but were variable. Further studies investigating predisposing factors are necessary to help prevent occurrence and enhance early clinical diagnosis and management of the condition.

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The National Comprehensive Cancer Network (NCCN) has published guidelines for hereditary breast and ovarian cancer syndrome (HBOCS) management. Little data exist on compliance with these guidelines among different physician specialties. We performed an on-line case-based survey by randomly sampling physicians from five specialties, Family Medicine (FM), Obstetrics and Gynecology (OG), General Surgery (GS), Internal Medicine (IM), and Hematology and Oncology (HO). The physicians (n = 225) were asked to provide HBOCS management of healthy women ages 40-42 in the presence of a familial BRCA1 mutation. For women negative for the BRCA1 mutation, 59% of the physicians recommended appropriate surveillance although with significant differences among specialties; P = 0.01. Using an aggregate screening intensity score, physicians clearly recommended more intense screening for mutation positive than negative women (P < 0.0001), but only 16% of physicians followed NCCN guidelines for BRCA1-positive women. Seventy-six percent of all physicians recommended breast MRI with significant variation among specialties ranging from 62% of FM to 89% of OG (P = 0.0020). Similarly, 63% of physicians recommended prophylactic oophorectomy, with 76 and 78% of GS and OG compared to 38% of IM (P < 0.0001) and 57% recommended prophylactic mastectomy ranging from 84% of HO to 32% of FM (P < 0.0001). Independent of specialty, respondents with BRCA testing experience recommended more intense management than those without; P = 0.021. Management recommendations of BRCA1 mutation carriers are not consistent with NCCN guidelines and vary by medical specialty and genetic testing experience. Targeted education of physicians by specialty is needed, so that optimal management is offered to these high-risk women.

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The Atacama Cosmology Telescope is a 6 m telescope designed to map the cosmic microwave background simultaneously at 145, 215, and 280 GHz with arcminute resolution. Each frequency will have a 32 by 32 element focal plane array of transition edge sensor bolometers. The telescope and the cold reimaging optics are optimized for millimeter-wave observations with these sensitive detectors. The design of each is described.

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The purpose of this study was to determine whether anticipatory guidance at well-child visits (WCV) that included early literacy development and the provision of books by the examining physician changed family literacy practices. It was conducted in an inner-city pediatric clinic that serves as the continuity practice site for pediatric and pediatric/internal medicine residents. There were 352 children (181 treatment: 171 control), aged 2 to 24 months, enrolled in this prospective, controlled study. The health care providers underwent training on literacy and on how to incorporate this information during WCV. Anticipatory guidance on safety, development, and early literacy was given to all parents. Additionally, the treatment group received an age-appropriate book at each WCV. There were 1,263 visits made (686 treatment, 577 control). Questionnaires were completed by parents on physician helpfulness and by physicians on parental receptiveness. Parental ratings on physician helpfulness were higher in the treatment group than in the control group (p<0.05). Physician's rating of parental receptiveness was also higher in the treatment group than in the control group (p<0.05). Two years after enrollment, mother-child pairs who received guidance and a book were two times more likely to report enjoyment in reading together than the controls who received guidance but no book. We conclude that anticipatory guidance that included early literacy development and distribution of books at WCV resulted in increased family literacy orientation, parental receptiveness, and perception of physician helpfulness.

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One particularly controversial form of laparoscopic hysterectomy is subtotal hysterectomy (LSH). LSH was first described by Semm. Since that report, several authors have reported their initial experience with vanous methods for LSH. A recent clinical commentary by Munro discussed the pros and cons of LSH in an editorial entitled "Supracervical Hysterectomy: A Time for Reprisal. In a recently published report, we discussed our initial experience with laparoscopic subtotal hysterectomy. The article reported our experiences utilizing bipolar instruments, an electromechanical morcellator, and other modifications of LSH we feel simplify and reduce the procedural operaríve time and potential intraoperative and postoperative complications.

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It is now possible to begin a difficult hysterectomy via laparoscopy with or without adnexal removal and then complete the operation vaginally. We report our successful experience with laparoscopically assisted vaginal hysterectomy in 62 of 68 patients. Techniques used for hemostatic separation of the uterus and adnexal pedicles included an automatic laparoscopic stapling device (49 cases), bipolar coagulation with sharp transection (11) and combined techniques (2). Minor complications occurred in four patients. Six patients had their operations converted from laparoscopy to laparotomy because of significant adhesions (three), large fibroids (two) and poor access due to obesity (one). The use of a stapling device required less anesthesia time (1 hour, 57 minutes, vs. 3 hours, 43 minutes), a smaller blood loss (145 vs. 247 mL) and shorter hospital stays (2.53 vs. 2.75 days) than did laparoscopic bipolar coagulation. However, the average hospital costs were greater for disposable automatic stapling devices and trocars when compared to bipolar coagulation techniques ($9,310 vs. $6,227). Postoperative patient satisfaction with the operation was high (98%), with a high rate of symptom resolution (95%). Laparoscopically assisted vaginal hysterectomy is a safe, effective operation in selected cases and may soon become a common alternative to abdominal hysterectomy in certain cases.

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Studies were conducted to evaluate the characteristics of red cells stored for 35 days following preparation from units of whole blood anticoagulated with citrate-phosphate-dextrose-adenine-one and two (CPDA-1 and CPDA-2) and maintained at 20 to 24 degrees C for 8 hours after phlebotomy. The mean (+/- 1 SD) 24-hour survival for transfused CPDA-1 autologous red cells with hematocrit levels of 78.1 +/- 2.3 percent was 78.0 +/- 8.1 percent (n = 9). The 24-hour survival of red cells from units preserved with CPDA-2 with hematocrit levels of 79.3 +/- 4.5 percent was 74.8 +/- 8.6 percent (n = 15). This difference in survival was not significant. Red cells from control units stored for 1 day showed a 24-hour survival of 91.9 +/- 4.2 percent (n = 7). During the 8-hour holding, red cell adenosine triphosphate levels increased by 15 to 25 percent in units drawn into both CPDA-1 and CPDA-2. After the initial 8-hour period, the red cell 2,3 diphosphoglycerate levels were 54 +/- 12 percent (mean +/- 1 SD) of initial levels in units drawn into CPDA-1 and 58 +/- 8 percent of initial levels in units drawn into CPDA-2. Following 35 days of storage, units of red cells prepared from whole blood drawn into CPDA-1 and CPDA-2 had comparable plasma cation and ammonia levels and similar amounts of cell-free hemoglobin. These data indicate that red cells can be stored satisfactorily for 35 days when prepared from whole blood held at 20 to 24 degrees C for 8 hours.

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A retrospective study from January 1, 1976, through July 31, 1981, was performed to evaluate the relationship between type of delivery and perinatal morbidity and mortality in twins of birth weight less than 2,000 gm. Vaginally delivered second twins who weighed 601 to 999 gm had increased risk of neonatal mortality when compared to their siblings. Among twins who weighed 1,000 to 1,499 gm, vaginally delivered second twins had significantly lower Apgar score and increased risks of neonatal morbidity in comparison to their siblings, whereas second twins who were delivered by cesarean section had no difference in Apgar score or neonatal morbidity from those of their siblings. In twins who weighed 1,500 to 1,999 gm, a significant increase in neonatal complications in vaginally delivered second twins was not found, although the majority of neonatal complications did occur in vaginally delivered second twins. Cesarean section is proposed as the optimal route of delivery for all twins expected to have a birth weight less than 1,500 gm.

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Plateletpheresis units collected using the Haemonetics Model 30 or the IBM 2997 cell separator were stored for 24 h at 22 degrees C. Autologous recovery and life span measurements averaged 64 +/- 13% (1 SD) and 8.9 +/- 1.3 (1 SD) days. The hemostatic effectiveness of these preparations were satisfactory; the corrected increment 4-6 h and 18-24 posttransfusion was 20,400 and 13,400/microliter/m2, respectively, and the bleeding time showed improvement in each patient. There was no significant difference in these parameters between collection devices.

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We studied the in vivo recovery, lifespan, and hemostatic effectiveness of CPDA-1 platelet concentrates stored for up to 72 hours at 4 C. A total of 120 CPDA-1 concentrates containing an average (+/- 1 S.D.) of 6.6 +/- 2.0 x 10(10) platelets were prepared. The pH of the units following storage at 4 C was 6.8 +/- 0.2; no unit had a pH below 6.3. Autologous transfusion of six normal volunteers showed that platelets stored at 4 C for 72 hours had an in vivo recovery of 40 +/- 18 per cent and a lifespan of 5.1 +/- 1.5 days. The hemostatic effectiveness of CPDA-1 platelets was determined by platelet counts and template bleeding time measurements in 10 thrombocytopenic patients. Patients receiving 48-hour-stored platelets had a four- to six-hour posttranfusion corrected platelet increment averaging 15,300 +/- 3,200/microliter which was 67 +/- 34 per cent of expected recovery. Four of the five patients transfused with this preparation showed an improved bleeding time. In contrast, three patients receiving 72-hour-stored platelets had a four- to six-hour posttransfusion increment of 5,800 +/- 2,400/microliter that was only 26 +/- 13 per cent of the expected recovery; furthermore, only one of these patients showed any correction of the bleeding time. These data indicate that CPDA-1 platelets are hemostatically effective when stored at 4 C for up to 48 hours.

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During the past five years, there has been a sharp increase in the use of packed RBCs (PRBCs) and plasma products, whereas whole blood (WB) transfusions have steadily decreased. In order to determine whether plasma and its derivatives were being used to "reconstitute" whole blood from PRBCs, we performed a retrospective evaluation of all transfusion episodes in ten representative regional hospitals during a five-month period. Our results indicate that PRBCs were transfused 2.5 times more frequently than WB. Plasma products were administered with PRBCs less often than with WB: 14% of all PRBCs vs 24% of all WB units tranfused. The likelihood of a patient receiving plasma was found to correlate with the total amount of blood transfused and the frequency of transfusion. This study provides evidence that, at most, only a small percentage of PRBCs are given in conjunction with plasma as "reconstituted" WB.

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