Search

When Rodney Blevins left the Dominion Energy regional operations center on June 29, 2012, he knew a storm was coming but was not worried. With routine storm planning and preparation, [...]

IMPORTANCE: O6-methylguanine-DNA methyltransferase (MGMT [OMIM 156569]) promoter methylation (mMGMT) is predictive of response to alkylating chemotherapy for glioblastomas and is routinely used to guide treatment decisions. However, the utility of MGMT promoter status for low-grade and anaplastic gliomas remains unclear due to molecular heterogeneity and the lack of sufficiently large data sets. OBJECTIVE: To evaluate the association of mMGMT for low-grade and anaplastic gliomas with chemotherapy response. DESIGN, SETTING, AND PARTICIPANTS: This cohort study aggregated grade II and III primary glioma data from 3 prospective cohort studies with patient data collected from August 13, 1995, to August 3, 2022, comprising 411 patients: MSK-IMPACT, EORTC (European Organization of Research and Treatment of Cancer) 26951, and Columbia University. Statistical analysis was performed from April 2022 to January 2023. EXPOSURE: MGMT promoter methylation status. MAIN OUTCOMES AND MEASURES: Multivariable Cox proportional hazards regression modeling was used to assess the association of mMGMT status with progression-free survival (PFS) and overall survival (OS) after adjusting for age, sex, molecular class, grade, chemotherapy, and radiotherapy. Subgroups were stratified by treatment status and World Health Organization 2016 molecular classification. RESULTS: A total of 411 patients (mean [SD] age, 44.1 [14.5] years; 283 men [58%]) met the inclusion criteria, 288 of whom received alkylating chemotherapy. MGMT promoter methylation was observed in 42% of isocitrate dehydrogenase (IDH)–wild-type gliomas (56 of 135), 53% of IDH-mutant and non-codeleted gliomas (79 of 149), and 74% of IDH-mutant and 1p/19q-codeleted gliomas (94 of 127). Among patients who received chemotherapy, mMGMT was associated with improved PFS (median, 68 months [95% CI, 54-132 months] vs 30 months [95% CI, 15-54 months]; log-rank P < .001; adjusted hazard ratio [aHR] for unmethylated MGMT, 1.95 [95% CI, 1.39-2.75]; P < .001) and OS (median, 137 months [95% CI, 104 months to not reached] vs 61 months [95% CI, 47-97 months]; log-rank P < .001; aHR, 1.65 [95% CI, 1.11-2.46]; P = .01). After adjusting for clinical factors, MGMT promoter status was associated with chemotherapy response in IDH–wild-type gliomas (aHR for PFS, 2.15 [95% CI, 1.26-3.66]; P = .005; aHR for OS, 1.69 [95% CI, 0.98-2.91]; P = .06) and IDH-mutant and codeleted gliomas (aHR for PFS, 2.99 [95% CI, 1.44-6.21]; P = .003; aHR for OS, 4.21 [95% CI, 1.25-14.2]; P = .02), but not IDH-mutant and non-codeleted gliomas (aHR for PFS, 1.19 [95% CI, 0.67-2.12]; P = .56; aHR for OS, 1.07 [95% CI, 0.54-2.12]; P = .85). Among patients who did not receive chemotherapy, mMGMT status was not associated with PFS or OS. CONCLUSIONS AND RELEVANCE: This study suggests that mMGMT is associated with response to alkylating chemotherapy for low-grade and anaplastic gliomas and may be considered as a stratification factor in future clinical trials of patients with IDH–wild-type and IDH-mutant and codeleted tumors.

Background Previous investigations have shown a positive association between hospital volume of operations and clinical outcomes. However, it is unclear whether such relationships also apply to emergency surgery. We sought to examine the association between hospital case volume and inpatient mortality for 7 common emergency general surgery (EGS) operations among geriatric patients.Methods This is a population based retrospective cohort study using the Centers of Medicare and Medicaid Services (CMS) Limited Dataset Files (LDS) from 2011 to 2013. The 7 most common emergency surgeries included (1) partial colectomy, (2) small-bowel resection (SBR), (3) cholecystectomy, (4) appendectomy, (5) lysis of adhesions (LOA), (6) operative management of peptic ulcer disease (PUD), and (7) laparotomy with the primary outcome being inpatient mortality. Risk-adjusted inpatient mortality was plotted against operative volume. Subsequently an operative volume threshold was calculated using a best fit regression method. Based on these estimates, high- and low-volume hospitals were compared to examine significance of outcomes. Significance was defined as P-value < .05.Results The final cohort comprised of 414 779 patients from 3994 hospitals. The standardized mortality ratio (SMR) for high-volume centers were lower in 6 out of 8 surgeries examined. Small-bowel resection and partial colectomy operations had a significant decrease in mortality based on a volume threshold.Conclusion We observed decreased mortality with higher surgical volume for small-bowel resection and partial colectomy operations. Such differences may be related to practice patterns during the perioperative period, as complications related to the perioperative care were significantly lower for high-volume centers.

Background Investigations detailing predictive measures of hospital disposition after traumatic injury are scarce. We aim to examine the discharge practices among trauma centers in the US and to identify factors that may influence post-hospital disposition.Methods A retrospective analysis of trauma patients using the American College of Surgeons-Trauma Quality Improvement Program dataset from 2007-2017. Primary study outcome was hospital disposition (including long term care facility [LTC], others). Secondary outcomes included: Intensive Care Unit (ICU)-length of stay (LOS), complications, others).Results 6 899 538 patients were analyzed. Odds of LTC discharge was significantly higher for Black patients (aOR = 1.30, 95% CI:1.24-1.37), abbreviated injury score (AIS) ≥3 (aOR = 4.22, 95% CI: 4.05-4.39), and higher injury severity score (ISS) (aOR = 9.41, 95% CI:9.03-9.80). Significantly more self-pay patients were discharged home compared to other insurance types (P< .0001). Significantly longer hospital- and ICU-LOS were experienced by those who had an AIS ≥3 (hospital: 4.8 days (±7.1) vs. 7.9 (±10.1); ICU: 4.6 (±6.9) vs. 5.9 (±7.9), P< .0001) and had a high ISS (hospital: 4.5 days (±5.9) vs. 16.8 (±17.9); ICU: 3.6 (±5.0) vs. 10.2 (±11.5), P< .0001).Conclusions Patient race, insurance status, and injury severity were predictive of post-hospitalization care discharge. Self-pay and Black patients were less likely to be discharged to secondary care facilities. These findings have the potential to improve in-hospital patient management and predict discharge secondary care needs, and necessitate the need for future research to investigate the extent of inequalities in access to trauma care.

Background Hemorrhage accounts for >30% of trauma-related mortalities. Use of resuscitative endovascular balloon occlusion of the aorta (REBOA) for temporary hemostasis in the civilian population remains controversial. We aim to investigate REBOA practices through analysis of surgeon and trauma center characteristics, implementation, patient characteristics, and overall opinions.Methods An anonymous 30-question standardized online survey on REBOA use was administered to active trauma surgeon members of the Eastern Association for the Surgery of Trauma.Results A total of 345 responses were received, and 130/345 (37.7%) reported REBOA being favorable, 42 (12.2%) reported REBOA unfavorably, and 173 (50.1%) were undecided. The majority of respondents (87.6%) reported REBOA performance in the trauma bay. 170 (49.3%) of respondents reported having deployed REBOA at least once over the past 2 years. 80.0% reported blunt trauma being the most common mechanism of injury in REBOA patients. Resuscitative endovascular balloon occlusion of the aorta deployment in zone 3 of the aorta was significantly higher in patients reported to suffer a pelvic fracture or pelvic hemorrhage, whereas REBOA deployment in zone 1 was significantly higher among patients reported to suffer hepatic, splenic, or other intra-abdominal hemorrhage (P< .05).Conclusion Among survey respondents, frequency of REBOA use was low along with knowledge of clear indications for use. While current REBOA usage among respondents appeared to model current guidelines, additional research regarding REBOA indications, ideal patient populations, and outcomes is needed in order to improve REBOA perception in trauma surgeons and increase frequency of use.

Background The data on resuscitative endovascular balloon occlusion of the aorta (REBOA) use continue to grow with its increasing use in trauma centers. The data in her last 5 years have not been systematically reviewed. We aim to assess current literature related to REBOA use and outcomes among civilian trauma populations.Methods A literature search using PubMed, EMBASE, and JAMA Network for studies regarding REBOA usage in civilian trauma from 2016 to 2020 is carried out. This review followed preferred reporting items for systematic reviews and meta-analysis guidelines.Results Our search yielded 35 studies for inclusion in our systematic review, involving 4073 patients. The most common indication for REBOA was patient presentation in hemorrhagic shock secondary to traumatic injury. REBOA was associated with significant systolic blood pressure improvement. Of 4 studies comparing REBOA to non-REBOA controls, 2 found significant mortality benefit with REBOA. Significant mortality improvement with REBOA compared to open aortic occlusion was seen in 4 studies. In the few studies investigating zone placement, highest survival rate was seen in patients undergoing zone 3. Overall, reports of complications directly related to overall REBOA use were relatively low.Conclusion REBOA has been shown to be effective in promoting hemodynamic stability in civilian trauma. Mortality data on REBOA use are conflicting, but most studies investigating REBOA vs. open occlusion methods suggest a significant survival advantage. Recent data on the REBOA technique (zone placement and partial REBOA) are sparse and currently insufficient to determine advantage with any particular variation. Overall, larger prospective civilian trauma studies are needed to better understand the benefits of REBOA in high-mortality civilian trauma populations.Study Type Systematic Review.Level of evidence III- Therapeutic.

•The 2011 Duty Hour Restrictions did not result in significant improvement in patient outcomes•Resident satisfaction was not improved after DHR implementation, with many reporting concern over clinical responsibilities•Resident wellness interventions may be improved by giving residents flexibility in setting their work limitations•Resident wellness is a multifactorial issue that must be handled beyond hour restrictions alone

Limited water availability has regulators, water management districts and municipalities looking for drought-proof, reliable water supplies. Seawater desalination is a technically viable solution to the water shortages in the United [...]

Burnout is a significant and increasingly recognized issue. They aimed to investigate burn surgeons’(BSurg) perceptions regarding burnout, contributing factors, and implications to better identity possible targeted interventions. A 42-question anonymous online survey was distributed by the ABA to BSurg members. Respondents included BSurgs in university or nonuniversity hospital settings. Experience of burnout was reported among 89.8% of university and 84.6% of nonuniversity hospital-affiliated respondents. After adjusting for confounders, university BSurgs exhibited a higher risk of perceived burnout compared with nonuniversity settings (aOR: 1.081, 95% CI: 0.237, 4.937). Women BSurgs were at 5 times higher risk of reporting burnout compared with men (aOR: 5.048, 95% CI: 0.488, 52.255). BSurgs aged 40 to 44 had twice the risk of reporting burnout as ≥50 (aOR: 1.985, 95% CI:0.018, 216.308). Practicing for 21 to 30 years had 12 times higher risk of reporting burnout than practicing >30 (aOR: 12.264, 95% CI: 0.611, 246.041). Those working <50 hr/wk reported burnout more frequently than those who work ≥80 hr/wk (aOR: 2.469, 95% CI: 0.80, 76.662). Overall reports of burnout were high amongst burn surgeon respondents. Those with 21 to 30 years of clinical practice were at significantly higher risk of reporting burnout despite believing that their colleagues’ burnout was more frequent than their own. Interventions addressing perceived burnout in younger burn surgeons may be limited by lack of participation due to fear of repercussions from administration or peers. Future administration-led burnout initiatives should acknowledge the differences between burn surgeon groups and offer resources unique to the individual physician’s needs for burnout prevention to be successful.

Background Patients with major trauma and contraindications to anticoagulation are often considered candidates for a prophylactic inferior vena cava filter (IVCF). Prophylactic IVCFs are controversial in trauma and backed by varying levels of evidence. This study aims to analyze outcomes in severely injured patients who receive IVCFs.Methods A retrospective review of trauma patients aged ≥ 16 years with ISS ≥ 15 admitted to our level 1 trauma center from years 2013 through 2018. Patients were divided into 2 groups: prophylactic IVCF versus VTE chemoprophylaxis. The analysis evaluated demographics, stratified by ISS (15-24, 25-34, ≥35), and subgrouped those with AIS-Head ≥3. Adjusted outcome measures included DVT, PE, mortality, and ICU length-of-stay (ICU-LOS).Results The study sample included 413 patients with prophylactic IVCFs and 2487 on VTE chemoprophylaxis. IVCF placement was associated with higher severity injuries: ISS 28 versus 25 and lower GCS 10.0 versus 11.8, TBI prevalence 83% versus 68% (P< .001). Patients with IVCFs had increased ICU-LOS (23.2 days vs 12.2 days), DVT (14.8% vs 4.3%), and PE (5.8% vs 1.6%) for patients with ISS <35 (P< .001). ISS ≥35 was not associated with intergroup DVT or PE rate differences (P= .81 and .43). No intergroup mortality differences were observed, including after ISS stratification. Among patients with AIS-Head ≥3, prophylactic IVCF was associated with lower in-hospital mortality (8.4% vs 15.7%, P= .001).Conclusions Prophylactic IVCF placement was associated with higher rates of DVT and nonfatal PE, and prolonged ICU-LOS. Prophylactic IVCF placement was not associated with increased in-hospital mortality for severely injured trauma patients. Among patients with concomitant critical head injuries (AIS-Head ≥3), prophylactic IVCF placement was associated with lower in-hospital mortality than VTE chemoprophylaxis.

Education is essential for lowering cases of Angiostrongyliasis in Hawaii. A professional development course on rat lungworm disease (RLWD) prevention was offered to Hawaii K-12 teachers during the 2018–2019 school year. Fourteen teachers, 11 from Hawaii Island and three from Maui, representing grades K, 2, 6–8, and 10−12, completed workshops and activities and received course credit. Teachers reached 652 students and educated 86 teachers and staff and approximately 900 community members including parents. A pre-course survey showed 55% of teachers agreed to a basic understanding of rat lungworm and its impact on Hawaii; this increased to 100% post-course. A sixth-grade class was the first to document the arrival of a highly competent intermediate host of the rat lungworm in a new location, an important discovery that initiated community awareness and control efforts. Six, 1-day workshops were held in 2018–2019, each on one of the main Hawaiian Islands. These were attended by 106 participants including teachers, community educators, and interested individuals from agencies, non-profits, businesses and the private sector. Of participants surveyed, 100% responded the workshop improved their overall understanding of RLWD. Efforts are being made to continue these programmes. [ABSTRACT FROM AUTHOR]

•These two cases highlight the limitations in current grading systems, particularly in the context of gallbladder size.•We propose modifications to the PGS to include not only abnormal anatomy but instances of distorted gallbladder anatomy due to inflammation and/or the large to giant size in order to account for the increased risk of complications.•Both distorted gallbladder anatomy and giant gallbladder size can make laparoscopic cholecystectomy a challenge, and thus warrant contribution to overall clinical grade.•While the PGS, Tokyo Guidelines, and AAST grading scales are validated grading scales for acute cholecystitis, additional modifications can further characterize different types of acute cholecystitis to better guide patient management.

Physician scientists who are also Editorial Board members or Associate Editors may prefer publishing in their own journal and therefore create an environment for conflicts of interest to arise.

The literature remains unclear on the development, consequences, and interventions for burnout in resident populations. We aim to identify the prevalence and nuances of reported burnout in general surgery resident physicians to better understand which factors contribute the greatest risk.

Background Prophylactic inferior vena cava filters (IVCFs) are often placed in trauma patients who cannot receive prophylactic anticoagulation. IVCFs are utilized in an effort to reduce the risk of acute pulmonary embolism (PE) and mortality. This study aims to investigate whether time-to-filter placement is associated with differences in trauma outcomes.Methods We conducted a single-center retrospective review of adult trauma patients who underwent prophylactic IVCF placement. Patients were divided into 2 groups based on time-to-filter: 0-48 hours and >48 hours. Outcome measures included post-filter deep vein thrombosis (DVT), post-filter PE, in-hospital mortality, and ICU length of stay (ICU-LOS). Significance was defined as P< .05.Results During the 6-year study period, 513 patients underwent prophylactic IVCF placement. Both groups were similar with respect to injury severity score (ISS) (P= .540), percent of patients on home anticoagulation (38% and 39%, P= .845), abbreviated injury scale (AIS) by anatomic region (P= .899), and traumatic brain injury (TBI) prevalence (P= .182). Time-to-filter was not associated with significant differences in DVT, PE, or in-hospital mortality (P> .05 for all). Filter placement in the first 48 hours was associated with shorter ICU-LOS and hospital-LOS.Conclusions Currently, there are no investigations in the trauma literature looking at the impact of time-to-filter on complications related to venous thromboembolism and potential survival benefit. Results of this investigation showed that IVCF placement within the first 48 hours was significantly associated with shorter ICU- and hospital- LOS.

Subclavian artery injury secondary to blunt trauma is rare and only a few cases have been documented in the literature. Subclavian arteries are protected by the clavicles, ribs, and chest wall. Clinical management and surgical approach vary depending on the specific injury. We present the case of a 50 year old male with blunt right subclavian transection.

Although radiation is widely used to treat cancers, resistance mechanisms often develop and involve activation of DNA repair and inhibition of apoptosis. Therefore, compounds that sensitize cancer cells to radiation via alternative cell death pathways are valuable. We report here that ferroptosis, a form of nonapoptotic cell death driven by lipid peroxidation, is partly responsible for radiation-induced cancer cell death. Moreover, we found that small molecules activating ferroptosis through system xc–inhibition or GPX4 inhibition synergize with radiation to induce ferroptosis in several cancer types by enhancing cytoplasmic lipid peroxidation but not increasing DNA damage or caspase activation. Ferroptosis inducers synergized with cytoplasmic irradiation, but not nuclear irradiation. Finally, administration of ferroptosis inducers enhanced the antitumor effect of radiation in a murine xenograft model and in human patient-derived models of lung adenocarcinoma and glioma. These results suggest that ferroptosis inducers may be effective radiosensitizers that can expand the efficacy and range of indications for radiation therapy.

Open quantum systems often operate in the non-Markovian regime where a finite history of a trajectory is intrinsic to its evolution. The degree of non-Markovianity for a trajectory may be measured in terms of the amount of information flowing from the bath back into the system. In this study, we consider how information flows through the auxiliary density operators (ADOs) in the hierarchical equations of motion. We consider three cases for a range of baths, underdamped, intermediate, and overdamped. By understanding how information flows, we are able to determine the relative importance of different ADOs within the hierarchy. We show that ADOs sharing a common Matsubara axis behave similarly, while ADOs on different Matsubara axes behave differently. Using this knowledge, we are able to truncate hierarchies significantly, thus reducing the computation time, while obtaining qualitatively similar results. This is illustrated by comparing 2D electronic spectra for a molecule with an underdamped vibration subsumed into the bath spectral density.

Purpose: Receiving weight loss advice from a health-care provider has been associated with more weight loss efforts and greater odds of achieving weight loss. However, whether patients seek help from their provider or other health professional with weight loss after receiving advice from them to lose weight is largely unknown.Design: Cross-sectional data from the 2011 to 2012 National Health and Nutrition Examination Survey (NHANES).Sample: A total of 3862 overweight/obese adults.Measures: Questionnaires asked whether participants received advice to lose weight, and whether they sought health professional’s assistance with weight management. The NHANES 2011 to 2012 was the most recent year both questions were asked.Analysis: Accounting for NHANES sampling and design, frequency distributions characterized demographics and proportions. Logistic regressions estimated odds of seeking weight loss help by demographics.Results: Of 3682 overweight/obese adults, 1908 were told they were overweight or recommended to lose weight. Of 1908 people, 68% reported weight loss efforts, but only health 10.9% sought a health professional’s help (dietician/nutritionist 4.7%, personal trainer 3.0%, doctor 2.8%). Females, people with health insurance and high health-care utilization had 1.5 to 3.5 times greater odds of seeking help; age, ethnicity, and income were not significantly associated with seeking help with weight management.Conclusion: In a nationally representative sample, only 10.9% of overweight/obese adults told to lose weight by a provider sought help from a health professional with weight loss. This underscores the opportunity for greater health professional involvement with weight management beyond giving recommendations.

Background Vitamin D (VitD) and calcium (Ca) supplementation attenuates antiretroviral therapy (ART)-associated bone loss, but it is unclear whether this effect is mediated through immunomodulation.Methods In this exploratory analysis of A5280, a 48-week, randomized, double-blind, placebo-controlled study of VitD/Ca supplementation with ART initiation, we characterized lymphocyte phenotypes and receptor activator of nuclear factor kappa-B ligand (RANKL) expression by median fluorescence intensity (MFI) at baseline and 48 weeks. Changes were evaluated within and between treatment groups by Wilcoxon signed rank and rank sum tests, respectively. Spearman correlations estimated relationships between cellular phenotypes and bone mineral density (BMD).Results Of 165 participants enrolled, 138 had samples for cellular phenotypes (64 VitD/Ca, 74 placebo). Markers of CD4, CD8 activation (CD38+HLA-DR+) declined (all P<0.001), but did not differ between arms. There was no decline in either %T-cells (CD4 and CD8) expressing RANKL or expression of RANKL by MFI. CD4 and CD8 activation markers were not correlated with BMD at baseline (r<0.15 and P>0.09 for all), but greater declines in CD4 activation correlated with greater declines in hip and spine BMD in both arms (0.25 =r =0.37, all P<0.05). A greater decline in CD8 activation was correlated with greater declines in both hip and spine BMD in the placebo arm only (hip r=0.31, P=0.009; spine r=0.25, P=0.035).Conclusions Reductions in T-cell activation are characteristic of ART initiation, but only correlated modestly with bone loss. VitD/Ca supplementation does not appear to mitigate bone loss through modulation of immune activation or expression of RANKL. Trial registration number: NCT01403051.

OK, I've tried everything so far to the best of my ability, but every time I try to put on red-trimmed white number plate back-grounds on my CRF450R, everything goes […]

O6-methylguanine-DNA-methyltransferase (MGMT) is a crucial DNA repair protein that removes DNA adducts formed by alkylating mutagens. Several coding single nucleotide polymorphisms (cSNPs) in the MGMTgene have been reported. Their biological significance, however, is not known.

O6-Methylguanine-DNA-methyltransferase (MGMT) is a direct-reversal DNA repair protein that removes DNA adducts formed by alkylating mutagens found in tobacco smoke. Several coding single nucleotide polymorphisms (cSNPs) in the MGMTgene have been reported. However, their effect on the levels and types of genetic damage induced by specific environmental carcinogens remains to be fully elucidated. We developed two novel genotyping techniques and used them, in conjunction with the mutagen-sensitivity assay, to test the hypothesis that the L84F and I143V cSNPs in the MGMTgene confer increased sensitivity to genetic damage induced by the alkylating tobacco-specific nitrosamine carcinogen NNK. Lymphocytes from 114 healthy volunteers were exposed in vitroto NNK, and the genotoxic response was assessed by measuring chromosome aberration (CA) frequencies. A significant (P<0.02) increase in NNK-induced CA was observed in cells from individuals with the 84F polymorphism compared to cells from individuals homozygous for the referent L84 allele. A significant positive interaction between this cSNP and smoking, gender and age was observed (P<0.03). In subjects with the variant 143V allele, significantly higher levels of NNK-induced CA were observed in males and in young subjects (<43 years old) compared to subjects homozygous for the referent I143 allele (P<0.02). Individuals who inherited two cSNPs had significantly higher levels of NNK-induced CA compared to individuals with none or with one cSNP (P<0.002). These new data suggest that the 84F and 143V cSNPs may alter the function characteristics of the MGMT protein, resulting in suboptimal repair of genetic damage induced by NNK

AbstractWest Chester University’s (WCU) USE-Tech Partners PT3program has been a catalyst for increasing interest in and cooperation for preparing technology-proficient teachers. Professors who can model technology integration are an important element in the success of current exemplary teacher training efforts. This article tells the story of how WCU, a Pennsylvania state university, has worked to infuse technology into its teacher preparation efforts through faculty development. Project activities during a capacity-building year included monthly participant meetings, development of integration strategies by faculty, consortia partnership development, completion of the university technology plan, and project evaluation activities. Nineteen participating faculty had release time during spring or summer 2000 to develop and test integration strategies in one or more of their courses. Faculty enhanced the learning of preservice teachers through e-mail, the Internet and Web-based learning applications, content-specific software, and presentation software, as well as other productivity tools and videoconferencing.

Abstract: A pressure-transducer technique was developed for determining the transient distribution of pressure on a surface caused by the impact of a high-velocity jet. Jet parameters known to be effective in producing ring craters were selected for the study. The average jet velocity was 2100 ft/s (640 m/s) and its approximate diameter was 0.26 in. (0.66 cm). A hardened, small-diameter (0.039 in., 0.099 cm) lsquopressure pinrsquo was used to transmit the pressure from the impact surface to the pressure transducer. The average pressure was thus found over an area of 0.001192 in.2 (0.007690 cm2) at several locations within the impact area.Results show the greatest pressure to occur at the center of the impact area. These results refute the idea that ring craters are produced by the existence of higher pressures near the jet edge.

A test simulating the rain impact damage to two ceramic missile radomes traveling at supersonic speeds is described. A water-jet gun has been developed which fires a short burst of water at speeds up to 5000 ft/s (1524 m/s). This gun was used to simulate the impact of raindrops on the radomes. Equations are given relating the crater volume and area of a single jet impact to the energy of the jet. Then equations are given which express the cumulative damage as a function of impact angle, drop size distribution, velocity, and rain field length and intensity. A computer code has been written to solve these equations. The computer code gave results that agreed well with an actual rocket sled test. The code was used to predict the damage for a new set of conditions, and the water-jet gun was used on full-scale radomes to simulate the predicted rain impact damage.

Previously, assay conditions for the GUS enzyme have required lethal and/or destructive conditions which do not allow for the continued observation of living plants. The replacement of sodium phosphate buffer with potassium phosphate buffer and the removal of potassium ferrocyanide and EDTA resulted in an assay for the GUS enzyme that is both nondestructive and nonlethal to tobacco plants and therefore allows observations of tobacco roots through time.

Retailers should know their stocks - avoid problems - helps consumers.

No abstract available for this article.

A letter to the editor is presented in response to the changes in the magazine "ForbesLife."