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Sightings of unidentified flying objects (UFOs) or unidentified anomalous phenomena (UAP) have been reported throughout history. Given the potential security and safety risks they pose, as well as scientific curiosity, there is increasing interest in understanding what these sighting reports represent. We approach this problem as an important one of the human experience and that can be examined through a geographical lens: what local factors may increase or decrease the number of sighting reports? Using a Bayesian regression method, we test hypotheses based on variables representing sky view potential (light pollution, tree canopy, and cloud cover) and the potential for objects to be present in the sky (aircraft and military installations). The dependent variable includes over 98,000 publicly reported UAP sightings in the conterminous United States during the 20-year period from 2001 to 2020. The model results find credible correlations between variables that suggest people see more "phenomena" when they have more opportunity to. This analysis is one of few investigations of UAP sighting reports at a national scale providing context to help examine individual reports. Given that these objects are labeled unidentifiable in the personal sense, there are many natural and/or human based explanations worth exploring.

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Coiled-coil proteins are assemblies of two to four alpha-helices that pack together in a parallel or anti-parallel fashion. Coiled-coil structures can confer a variety of functional capabilities, which include enabling proteins, such as myosin, to function in the contractile apparatus of muscle and non-muscle cells. The TlpA protein encoded by the virulence plasmid of Salmonella is an alpha-helical protein that forms an elongated coiled-coil homodimer. A number of studies have clearly established the role of TlpA as a temperature-sensing gene regulator, however the potential use of a TlpA in a thermo-sensor application outside of the organism has not been exploited. In this paper, we demonstrate that TlpA has several characteristics that are common with alpha-helical coiled-coils and its thermal folding and unfolding is reversible and rapid. TlpA is extremely sensitive to changes in temperature. We have also compared the heat-stability of TlpA with other structurally similar proteins. Using a folding reporter, in which TlpA is expressed as a C-terminal fusion with green fluorescent protein (GFP), we were able to use fluorescence as an indicator of folding and unfolding of the fusion protein. Our results on the rapid conformational changes inherent in TlpA support the previous findings and we present here preliminary data on the use of a GFP-TlpA fusion protein as temperature sensor.

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Diatoms are of interest to the materials research community because of their ability to create highly complex and intricate silica structures under physiological conditions: what these single-cell organisms accomplish so elegantly in nature requires extreme laboratory conditions to duplicate-this is true for even the simplest of structures. Following the identification of polycationic peptides from the diatom Cylindrotheca fusiformis, simple silica nanospheres can now be synthesized in vitro from silanes at nearly neutral pH and at ambient temperatures and pressures. Here we describe a method for creating a hybrid organic/inorganic ordered nanostructure of silica spheres through the incorporation of a polycationic peptide (derived from the C. fusiformis silaffin-1 protein) into a polymer hologram created by two-photon-induced photopolymerization. When these peptide nanopatterned holographic structures are exposed to a silicic acid, an ordered array of silica nanospheres is deposited onto the clear polymer substrate. These structures exhibit a nearly fifty-fold increase in diffraction efficiency over a comparable polymer hologram without silica. This approach, combining the ease of processability of an organic polymer with the improved mechanical and optical properties of an inorganic material, could be of practical use for the fabrication of photonic devices.

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OBJECTIVE: The authors set out to determine whether immediate enteral feeding minimizes early postoperative decreases in handgrip and respiratory muscle strength. SUMMARY BACKGROUND DATA: Muscle strength decreases considerably after major surgical procedures. Enteral feeding has been shown to restore strength rapidly in other clinical settings. METHODS: A randomized, controlled, nonblinded clinical trial was conducted in patients undergoing esophagectomy or pancreatoduodenectomy who received immediate postoperative enteral feeding via jejunostomy (fed, n = 13), or no enteral feeding during the first 6 postoperative days (unfed, n = 15). Handgrip strength, vital capacity, forced expiratory volume in one second (FEV1), and maximal inspiratory pressure (MIP) were measured before surgery and on postoperative days 2, 4, and 6. Fatigue and vigor were evaluated before surgery and on postoperative day 6. Mobility was assessed daily after surgery using a standardized descriptive scale. Postoperative urine biochemistry was evaluated in daily 24-hour collections. RESULTS: Postoperative vital capacity (p < 0.05) and FEV1 (p = 0.07) were consistently lower (18%-29%) in the fed group than in the unfed group, whereas grip strength and maximal inspiratory pressure were not significantly different. Postoperative mobility also was lower in the fed patients (p < 0.05) and tended to recover less rapidly (p = 0.07). Fatigue increased and vigor decreased after surgery (both p < or = 0.001), but changes were similar in the fed and unfed groups. Intensive care unit and postoperative hospital stay did not differ between groups. CONCLUSIONS: Immediate postoperative jejunal feeding was associated with impaired respiratory mechanics and postoperative mobility and did not influence the loss of muscle strength or the increase in fatigue, which occurred after major surgery. Immediate postoperative enteral feeding should not be routine in well-nourished patients at low risk of nutrition-related complications.

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To evaluate the influence of aging on the increase in endogenous glucose production that follows injury, we studied 22 fully resuscitated, clinically stable, previously healthy patients aged < or = 30 yr or > or = 60 yr admitted to hospital following injury, and 11 healthy volunteers in the same age groups. Endogenous glucose production was determined using a primed constant infusion of D-glucose-6,6-2d2. Urine cortisol and C-peptide were markedly higher in patients than volunteers (both P < 0.01), and urine C-peptide was lower in older than in younger patients (P < 0.05). Urine cortisol increased as a function of the interaction of age and Injury Severity Score (ISS) (r2 = 0.40, P < 0.001). Intracellular water was markedly lower and extracellular water greater in patients compared with volunteers (both P < 0.001), reflecting the loss of body cell mass and expansion of the extracellular space following injury. Endogenous glucose production (milligrams per minute per liter intracellular water) was best described as a function of ISS and age-ISS interaction (r2 = 0.35, all P < 0.05), and was increased 56% and 78% in younger and older patients, respectively, in comparison with the respective volunteer groups. Endogenous glucose production following injury increases in relation to the severity of injury and patient age. Greater cortisol elaboration and diminished insulin secretion in older patients may contribute to this age effect.

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OBJECTIVE: To determine the effect of age on the blood glucose and insulin responses to a clinical model of glucose loading (i.e., total parenteral nutrition [TPN] with hypertonic glucose), in patients with a variety of conditions. DESIGN: A prospective cohort study. SETTING: An adult university hospital. PATIENTS: Seventy-one consecutive, clinically stable patients receiving central TPN, excluding those with metabolic disease or receiving relevant medications. INTERVENTION: None. MAIN OUTCOME MEASURES: Serum levels of glucose, insulin, C-peptide and cortisol determined in peripheral venous blood obtained immediately before initiating TPN and again 48 to 96 hours later; acute physiology score (APS) and habitual level of physical activity (HAL). RESULTS: Serum levels of glucose, insulin and C-peptide increased following initiation of TPN (all p < 0.001). The serum glucose level during TPN administration increased as a function of both patient age and severity of illness (APS) (r2 = 0.37, all p < 0.01), whereas the serum insulin level was inversely related to age and increased as a function of serum glucose, glucose rate of infusion and HAL (r2 = 0.57, all p < 0.05). The serum C-peptide: insulin molar ratio did not vary with age. CONCLUSIONS: Aging and severity of illness interact to exaggerate the increases in blood glucose that accompany TPN with hypertonic glucose. Serum insulin responses to TPN decline with aging, likely reflecting reduced insulin secretion. Diminished insulin responses may contribute to hyperglycemia and represent a diminished anabolic signal in such patients. The acutely ill elderly patient is predisposed to hyperglycemia and should be monitored carefully even when pre-TPN blood glucose values are normal.

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OBJECTIVE: To compare the effects of laparoscopic and open surgical procedures on postoperative strength and respiratory mechanics. DESIGN: Prospective cohort study. SETTING: Adult university hospital. PARTICIPANTS: Fifty-one women aged 21 to 62 years scheduled to undergo elective cholecystectomy or hysterectomy (or related procedures), otherwise in good health. INTERVENTIONS: Open or laparoscopic cholecystectomy or hysterectomy (or related procedures). MAIN OUTCOME MEASURES: Maximum voluntary handgrip strength (HGS), forced vital (VC), forced expiratory volume in 1 second (FEV1), and maximal inspiratory pressure (MIP) were each measured preoperatively and on the first postoperative morning. A visual analogue pain scale score was evaluated in relation to performance of the postoperative strength and respiratory measurements. RESULTS: VC, FEV1, and MIP, but not HGS, were decreased after surgery. Postoperative VC, FEV1, and MIP were lower after open procedures than after laparoscopic procedures and after cholecystectomy than after hysterectomy (all p < 0.001). Pain scores were lower after laparoscopic than after open procedures (p < 0.005) and could account in part for differences in postoperative respiratory mechanics. CONCLUSIONS: Cholecystectomy and hysterectomy do not result in generalized muscle weakness, unlike more major abdominal procedures. Postoperative alterations in respiratory mechanics are related to the site of the surgery, the use of an open versus a laparoscopic approach and postoperative pain.

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This project had some unique components which may have played a significant role in assuring its success. For several months prior to the initiation of the project, the author had worked with the local people developing a rapport and helping them assess their needs and interests. The research was then initiated at their invitation and with their enthusiastic support. There was also a well-organized, local, leadership network in place which provided stability throughout the research project. The support and personal involvement of locally acknowledged leaders assisted greatly in gaining access into the homes of the batey mothers who consented to be interviewed. These same local leaders continued to lend support to the CHWs as they implemented their findings. The validity of the findings was very possibly enhanced by the use of CHW participants from the group studied. Informants frequently are more willing to share openly with someone from a similar value system than with a foreign researcher. In addition, the fact that the researcher, CHWs, and informants were all of the same sex no doubt contributed to the success of the method. The requirements of the participatory method which were encountered in this study would need to be carefully addressed in similar research projects conducted in Third World countries. Gaining entrée into a research site, addressing language and cultural differences, identifying participant researchers who were literate, arranging transportation to isolated sites for the interview component of the process, and allowing sufficient time to be on-site personally to conduct the project were a few of the challenges encountered in this study. Researchers conducting projects of this type should also guard against raising false hopes of change among the participants. Limitations should be identified at the onset of the project and participants reminded that the success of the program should be projected realistically. In spite of the challenges, this participatory research project using CHWs in the Dominican Republic was successful for a number of reasons: (a) local leaders supported the project and chose the CHWs who became the participant researchers; (b) the CHWs were literate and eager to learn; (c) the mothers were willing to share their beliefs and perceptions with the CHWs; (d) analysis of the data provided helpful new insights; (e) results of the analysis were immediately implemented in the health projects; and (f) the CHWs who participated demonstrated increased self-confidence and decision-making ability as they progressed through the process.(ABSTRACT TRUNCATED AT 400 WORDS)

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Regardless of where they live or under what circumstances, mothers throughout the world seem to have a compelling desire to provide the best possible health care for their children (Huston, 1979). Haitian mothers living in the Dominican Republic were no exception. The health beliefs and practices of these mothers related primarily to diarrhea among their children which demonstrated a concern and resourcefulness that is commendable. The results of this study clearly indicate the importance of transcultural nurses conducting culturally relevant research as a basis to develop sound health programs in developing countries. Diarrhea was identified as the single most important threat to a child's health in these communities. That mothers did not know about the correct ingredients and/or proportions for oral rehydration solutions (Western views) was of interest. Although the Dominican government makes some commercial packets of ORS, most of the women interviewed did not have ready access to this product. This finding reflected the need for transcultural nurses to offer to teach mothers how to make ORS using the sugar, salt, and water they had available. Since the mothers' perception that diarrhea was a dangerous threat to their children's health, was verified by childhood mortality statistics in the bateys, it would seem that ORS could make a significant impact on the health status of the children. Breastfeeding also was a major health belief factor associated with the treatment of diarrhea. Even though the majority of mothers believed breast feeding should be continued if a child had diarrhea, a number believed it should be discontinued. Nurses working with CHWs will need to emphasize the importance of breastfeeding and help them to develop creative ways of communicating this information to the mothers. The second most dangerous threat to the child identified by the mothers was respiratory ailments. This suggests a new area of concentration for future research and training of CHWs. A host of new questions related to respiratory problems such as health beliefs, causative factors, course of disease, traditional treatments, mortality rate, etc. need to be investigated. When transcultural nurses plan health care programs for women and children in other cultures, it is important to recognize the concerns mothers have for their children, and their intense desire to nature and care for them. In this study, mothers willingly participated and demonstrated active interest in learning to use methods to improve the health and well being of their children. It is well documented (Lieban, 1977) that established health beliefs are not automatically discarded when new knowledge is made available, but that exploration and incorporation of new information when presented in a culturally relevant framework does occur. An understanding of local beliefs surrounding health is fundamental to the development of appropriate transcultural nursing interventions.

PIP: Interviews conducted by community health workers with 83 Haitian women working in sugar cane fields in the Dominican Republic underscored the importance of understanding local health beliefs so that culturally appropriate interventions are implemented. The respondents all had at least 1 child under 5 years of age; their average age was 29 years and they had a mean parity of 4.9. The mothers identified gastrointestinal problems, chiefly diarrhea, as the greatest threat to their child's health. 82% of the mothers had at one time had a diarrheal episode among her children and 31% reported that a child currently had diarrhea; 16% said at least 1 child had died of diarrhea. Water, food, and microbes were identified as the major cause of diarrhea. Although not routinely cited as a cause of diarrhea, the evil eye (transmitted by male of female witches) was viewed by all but 1 mother as a powerful factor in child mortality. The foods mothers claimed they would give a child with diarrhea included lemonade, soups, bananas, and other fruit juices. Both cooking oil and milk were considered harmful. Of concern was the finding that 38% of mothers would discontinue breastfeeding during a diarrhea episode. None of the mothers had heard of oral rehydration; however, most were treating diarrhea with a solution prepared by pouring boiling water over herbs and leaves. This practice suggests that these mothers can be instructed to prepare oral rehydration solutions in which all ingredients are precisely measured. Since diarrhea is a major cause of child mortality in these Haitian communities in the Dominican Republic, promotion of oral rehydration could make a significant contribution to child survival. It is essential, however, that all such interventions incorporate existing beliefs and present new information in a culturally relevant framework.

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The Hering-Breuer inspiratory inhibitory reflex was studied serially in a group of premature infants and in a group of term infants in the immediate postnatal period. The premature infants had a stronger inspiratory inhibitory reflex than did the term infants at birth; this reflex decreased with maturation of the premature. Development in the extrauterine environment significantly delayed the rate of disappearance of this reflex. This may indicate that premature delivery retards the neurologic maturation of the human infant. The term infant showed no change in the activity of the inspiratory inhibitory reflex in the first five days of life.

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1. Plasma renin (measured as rate of formation of angiotensin I ng/ml.hr(-1) in the presence of added substrate at pH 7.5 and 37 degrees C) was much lower in recently nephrectomized foetal, new-born and older lambs than in intact siblings or other similar lambs.2. Angiotensin II-like concentrations were measured using a superfusion technique in an extracorporeal circuit. Resting concentrations in acute experiments under anaesthesia were deduced by comparison of carotid blood of intact lambs with that from recently nephrectomized lambs.3. Angiotensin II-like activity (mean +/- S.E. of mean, 315 +/- 117 pg/ml.) was readily detectable in foetal blood at 123-138 days gestation. The highest concentrations (mean +/- S.E. of mean 839 +/- 96 pg/ml.) were found in lambs less than 8 hr old, delivered vaginally. The lowest concentrations of angiotensin II-like activity occurred in lambs delivered by Caesarean section (mean +/- S.E. of mean < 123 +/- 12 pg/ml.). Concentrations declined with post-natal age.4. Hypovolaemia as a result of haemorrhage evoked an increase in angiotensin II-like concentrations in foetus, new-born lambs and adult sheep. The greatest increase of angiotensin-like concentrations was seen in new-born lambs. This rise was associated with increase of plasma renin.5. The rise of arterial pressure during bilateral carotid occlusion in new-born lambs was accompanied by an increase of angiotensin II-like concentration.6. It is concluded that the renin-angiotensin system is functional and can be stimulated during intra-uterine life. The increase of angiotensin II-like concentration following parturition is probably transient and associated with the trauma of delivery. This contrasts with observations made in the rabbit which suggest that full functional maturity of the renin angiotensin system is delayed until the second week of life.

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