Evidence of a Hardening in the Cosmic Ray Proton Spectrum at around 166 TeV Observed by the GRAPES-3 Experiment.

We present the measurement of the cosmic ray proton spectrum from 50 TeV to 1.3 PeV using 7.81×10^{6} extensive air shower events recorded by the ground-based GRAPES-3 experiment between 1 January 2014 and 26 October 2015 with a live time of 460 day. Our measurements provide an overlap with direct observations by satellite and balloon-based experiments. The electromagnetic and muon components in the shower were measured by a dense array of plastic scintillator detectors and a tracking muon telescope, respectively. The relative composition of the proton primary from the air shower data containing all primary particles was extracted using the multiplicity distribution of muons which is a sensitive observable for mass composition. The observed proton spectrum suggests a spectral hardening at ∼166 TeV and disfavors a single power law description of the spectrum up to the Knee energy (∼3 PeV).

Deletion of G-protein-coupled receptor 55 promotes obesity by reducing physical activity.

BACKGROUND/OBJECTIVES: Cannabinoid receptor 1 (CB1) is the best-characterized cannabinoid receptor, and CB1 antagonists are used in clinical trials to treat obesity. Because of the wide range of CB1 functions, the side effects of CB1 antagonists pose serious concerns. G-protein-coupled receptor 55 (GPR55) is an atypical cannabinoid receptor, and its pharmacology and functions are distinct from CB1. GPR55 regulates neuropathic pain, gut, bone, immune functions and motor coordination. GPR55 is expressed in various brain regions and peripheral tissues. However, the roles of GPR55 in energy and glucose homeostasis are unknown. Here we have investigated the roles of GPR55 in energy balance and insulin sensitivity using GPR55-null mice (GPR55(-/-)). METHODS: Body composition of the mice was measured by EchoMRI. Food intake, feeding behavior, energy expenditure and physical activity of GPR55(-/-) mice were determined by indirect calorimetry. Muscle function was assessed by forced treadmill running test. Insulin sensitivity was evaluated by glucose and insulin tolerance tests. Adipose inflammation was assessed by flow cytometry analysis of adipose tissue macrophages. The expression of inflammatory markers in adipose tissues and orexigenic/anorexigenic peptides in the hypothalamus was also analyzed by real-time PCR. RESULTS: GPR55(-/-) mice had normal total energy intake and feeding pattern (i.e., no changes in meal size, meal number or feeding frequency). Intriguingly, whereas adult GPR55(-/-) mice only showed a modest increase in overall body weight, they exhibited significantly increased fat mass and insulin resistance. The spontaneous locomotor activity of GPR55(-/-) mice was dramatically decreased, whereas resting metabolic rate and non-shivering thermogenesis were unchanged. Moreover, GPR55(-/-) mice exhibited significantly decreased voluntary physical activity, showing reduced running distance on the running wheels, whereas muscle function appeared to be normal. CONCLUSIONS: GPR55 has an important role in energy homeostasis. GPR55 ablation increases adiposity and insulin resistance by selectively decreasing physical activity, but not by altering feeding behavior as CB1.

Ultracold collisions of O(1D) and H2: the effects of H2 vibrational excitation on the production of vibrationally and rotationally excited OH.

A quantum dynamics study of the O((1)D) + H2(v = 0 - 2, j = 0) system has been carried out using the potential energy surfaces of Dobbyn and Knowles [Mol. Phys. 91, 1107 (1997)]. A time-independent quantum mechanical method based on hyperspherical coordinates is adopted for the dynamics calculations. Energy dependent cross section, probability, and rate coefficients are computed for the elastic, inelastic, and reactive channels over collision energies ranging from the ultracold to thermal regimes and for total angular momentum quantum number J = 0. The effect of initial vibrational excitation of the H2 molecule on vibrational and rotational populations of the OH product is investigated as a function of the collision energy. Comparison of results for vibrational levels v = 0 - 2 of H2 demonstrates that the vibrational excitation of H2 and its non-reactive relaxation pathway play a minor role in the overall collisional outcome of O((1)D) and H2. It is also found that while the state-resolved product vibrational distributions are sensitive to the initial collision energy and H2 vibrational level, the product rotational distribution depicts an inverted population that is largely insensitive to initial conditions. Rate coefficients evaluated using a J-shifting approximation show reasonable agreement with available theoretical and experimental results suggesting that the J-shifting approximation may be used to evaluate the rate coefficients for O((1)D) + H2 reaction.

Chemical reaction versus vibrational quenching in low energy collisions of vibrationally excited OH with O.

Quantum scattering calculations are reported for state-to-state vibrational relaxation and reactive scattering in O + OH(v = 2 - 3, j = 0) collisions on the electronically adiabatic ground state (2)A'' potential energy surface of the HO2 molecule. The time-independent Schrödinger equation in hyperspherical coordinates is solved to determine energy dependent probabilities and cross sections over collision energies ranging from ultracold to 0.35 eV and for total angular momentum quantum number J = 0. A J-shifting approximation is then used to compute initial state selected reactive rate coefficients in the temperature range T = 1 - 400 K. Results are found to be in reasonable agreement with available quasiclassical trajectory calculations. Results indicate that rate coefficients for O2 formation increase with increasing the OH vibrational level except at low and ultralow temperatures where OH(v = 0) exhibits a slightly different trend. It is found that vibrational relaxation of OH in v = 2 and v = 3 vibrational levels is dominated by a multi-quantum process.

Infanticide and reproductive restraint in a polygynous social mammal.

Alpha male chacma baboons experience uncontested access to individual estrus females. Consequently, alpha male paternity certainty is high and underpins significant levels of infanticide by immigrant males that, in turn, has selected for male defense of infants. There is also, however, a high probability that alpha males will be absent during the period when their own offspring are vulnerable, suggesting selection for additional countermeasures. We use data from a long-term study to test the prediction that alpha male chacma baboons cede reproductive opportunities to subordinate males and that this leads to the presence of other fathers that can serve as a buffer against infanticidal attack. We found that subordinate males obtained significantly more conceptive opportunities than predicted by priority of access alone, and that this occurred because alpha males did not consort all receptive periods. There was no evidence that this was due to energetic constraint, large male cohorts, alpha male inexperience, or the competitive strength of queuing subordinates. The number of males who benefited from concession and the length of time that they were resident relative to those who did not benefit in this way greatly reduced the probability that infants of alpha males would face immigrant males without a surrogate father whose own offspring were vulnerable. The absence of such males was associated with observed infanticide as well as, unexpectedly, an increased likelihood of takeover when alpha males with vulnerable infants were present.

Exceptional phonon point versus free phonon coupling in Zn1-xBexTe under pressure: an experimental and ab initio Raman study.

Raman scattering and ab initio Raman/phonon calculations, supported by X-ray diffraction, are combined to study the vibrational properties of Zn1-xBexTe under pressure. The dependence of the Be-Te (distinct) and Zn-Te (compact) Raman doublets that distinguish between Be- and Zn-like environments is examined within the percolation model with special attention to x ~ (0,1). The Be-like environment hardens faster than the Zn-like one under pressure, resulting in the two sub-modes per doublet getting closer and mechanically coupled. When a bond is so dominant that it forms a matrix-like continuum, its two submodes freely couple on crossing at the resonance, with an effective transfer of oscillator strength. Post resonance the two submodes stabilize into an inverted doublet shifted in block under pressure. When a bond achieves lower content and merely self-connects via (finite/infinite) treelike chains, the coupling is undermined by overdamping of the in-chain stretching until a «phonon exceptional point¼ is reached at the resonance. Only the out-of-chain vibrations «survive¼ the resonance, the in-chain ones are «killed¼. This picture is not bond-related, and hence presumably generic to mixed crystals of the closing-type under pressure (dominant over the opening-type), indicating a key role of the mesostructure in the pressure dependence of phonons in mixed crystals.

High-resolution computed tomography evaluation of congenital aural atresia - how useful is this?

OBJECTIVE: To depict various temporal bone abnormalities on high-resolution computed tomography in congenital aural atresia patients, and correlate these findings with auditory function test results and microtia subgroup. METHODS: Forty patients (56 ears) with congenital malformation of the auricle and/or external auditory canal were evaluated. Auricles were graded according to Marx's classification, divided into subgroups of minor (grades I and II) and major (III and IV) microtia. Other associated anomalies of the external auditory canal, tympanic cavity, ossicular status, oval and round windows, facial nerve, and inner ear were evaluated. RESULTS: Minor and major microtia were observed in 53.6 and 46.4 per cent of ears respectively. Mean hearing levels were 62.47 and 62.37 dB respectively (p = 0.98). The malleus was the most commonly dysplastic ossicle (73.3 vs 80.8 per cent of ears respectively, p = 0.53). Facial nerve (mastoid segment) abnormalities were associated (p = 0.04) with microtia subgroup (80 vs 100 per cent in minor vs major subgroups). CONCLUSION: Microtia grade was not significantly associated with mean hearing levels or other ear malformations, except for external auditory canal and facial nerve (mastoid segment) anomalies. High-resolution computed tomography is essential in congenital aural atresia, before management strategy is decided.

Phonon-based partition of (ZnSe-like) semiconductor mixed crystals on approach to their pressure-induced structural transition.

The generic 1-bond → 2-mode "percolation-type" Raman signal inherent to the short bond of common A1-xBxC semiconductor mixed crystals with zincblende (cubic) structure is exploited as a sensitive "mesoscope" to explore how various ZnSe-based systems engage their pressure-induced structural transition (to rock-salt) at the sub-macroscopic scale-with a focus on Zn1-xCdxSe. The Raman doublet, that distinguishes between the AC- and BC-like environments of the short bond, is reactive to pressure: either it closes (Zn1-xBexSe, ZnSe1-xSx) or it opens (Zn1-xCdxSe), depending on the hardening rates of the two environments under pressure. A partition of II-VI and III-V mixed crystals is accordingly outlined. Of special interest is the "closure" case, in which the system resonantly stabilizes ante transition at its "exceptional point" corresponding to a virtual decoupling, by overdamping, of the two oscillators forming the Raman doublet. At this limit, the chain-connected bonds of the short species (taken as the minor one) freeze along the chain into a rigid backbone. This reveals a capacity behind alloying to reduce the thermal conductivity as well as the thermalization rate of photo-generated electrons.

An analysis of appendectomies performed in a Labrador general surgery practice.

INTRODUCTION: The main objective of our study was to determine the rates of negative appendectomies and perforated appendices at the Labrador Health Centre, and make a comparison with the rates published in the literature. METHODS: The study population consisted of all patients who underwent appendectomies during the 5-year period ending Apr. 3, 2006. The number and rates of negative appendectomies and perforated appendices were determined for each age and sex category. RESULTS: Of the 64 patients who were included in the study, 11% were found to have undergone negative appendectomies and 27% had perforated appendices. There was a clear trend toward decreasing perforation rates with increasing age as well as a trend toward increasing negative appendectomy rates with increasing age. CONCLUSION: The rates of negative appendectomies and perforated appendices at the Labrador Health Centre are comparable with those published in the literature. Trends found in the data will help to guide future improvements in patient management.

Laparoscopic TEP repair of inguinal hernia does not alter testicular perfusion.

PURPOSE: The effect of laparoscopic TEP repair on testicular perfusion is unclear. The procedure entails dissection of testicular blood vessels off the hernial sac and incorporation of a prosthetic mesh. This carries at minimum, a theoretical risk of compromise in testicular blood supply, which in turn may affect fertility. Our study aims to establish if any alteration in testicular perfusion occurs in very early (24 h), early (1 week) or late postoperative period (3 months) after laparoscopic TEP repair in the Indian population. METHODS: In our prospective trial, 20 patients underwent unilateral and 8 underwent bilateral laparoscopic TEP hernia repairs using standard technique by experienced surgeons. Flow parameters of testicular, capsular and intratesticular artery were noted using color Doppler ultrasound preoperatively and postoperatively and the postoperative resistive indexes of operated side (n = 36) were compared with preoperative values. Additionally, for unilateral repairs, flow parameters on operated side were compared with the non-operated side. RESULTS: No statistically significant difference was noticed in the resistive index of the arteries upon comparing these postoperative with preoperative values. For unilateral repairs, the flow parameters of the operated side were comparable with that of non-operated side (i.e. p > 0.05). CONCLUSION: Laparoscopic TEP performed by experienced surgeons does not alter testicular flow dynamics in early or late postoperative period.

Early Recognition of Fibrodysplasia Ossificans Progressiva-Important For the Clinician.

Fibrodysplasia ossificans progressiva is a rare disorder of heterotopic ossification. Procedures like biopsy and surgery are known to be aggravating factors in promoting heterotopic ossification Clues to clinical diagnosis may therefore be a great advantage to treating orthopedician. Valgus deformity of great toe is an important diagnostic clue for treating physicians and thus aids in preventing the clinicians from subjecting the patients to unnecessary invasive and traumatic procedures. Hence clinical clues to early diagnosis are important in establishing the correct diagnosis and directing future management.

Malignant melanoma metastatic to the esophagus.

A rare case of metastatic malignant melanoma of the esophagus 11 years after wide excision of a cutaneous malignant melanoma is presented and the relevant literature reviewed. Symptomatic esophageal metastasis is unusual in malignant melanoma. Although the eventual outlook is poor in such cases, worthwhile palliation can be achieved by prompt diagnosis and treatment.

Continuous intercostal nerve block for pain relief after thoracotomy.

Others have demonstrated the effectiveness of intercostal analgesia with bupivacaine hydrochloride (Marcain Plain; Astra). We present a greatly simplified method of effecting this. Our method is dependent on an intact pleura. To date, we have utilized this technique in 81 patients. Seventy-five (92.6%) required no additional analgesic in the first 24 hours following operation and 66 (81.5%), in the subsequent four days. Only 2 patients had postoperative pulmonary complications. No complication related either to the procedure or to the infusion of bupivacaine occurred. The technique as described here is a safe and reliable method of providing analgesia without any side effects after thoracotomy.

Deep vein thrombosis after total hip arthroplasty in Indian patients with and without enoxaparin.

PURPOSE: To study the incidence of deep vein thrombosis in Indian patients undergoing total hip arthroplasty with or without prophylaxis, and the effect of enoxaparin on deep vein thrombosis. METHODS: The study covered a total of 50 hips in 40 patients who underwent total hip arthroplasty. Patients were assessed for deep vein thrombosis using Doppler ultrasonography. The hips were numbered and divided into 2 groups: the odd-numbered hips did not receive any thrombo-prophylaxis, whereas the even-numbered hips received 40 mg of enoxaparin subcutaneously, once a day for 2 weeks, until the time of discharge. RESULTS: Deep vein thrombosis was not found in both groups. We found wound haematomas in 9 patients (all of whom were on enoxaparin) (p<0.05), superficial infection in 2 patients (one on enoxaparin, one not), and local bruising in 4 patients (all of whom were on enoxaparin). Major haemorrhage did not occur in any of the cases. CONCLUSION: The incidence of deep vein thrombosis in Indian patients is very low compared to that in European and American patients. Enoxaparin failed to provide any advantage to the patients. It is therefore not advisable to give prophylaxis/low-molecular-weight heparin for deep vein thrombosis to patients undergoing total hip arthroplasty without any risk factors.

Effect of exercise on acid-base status and ventilatory kinetics.

The normal respiratory responses and changes in acid base status in twenty normal height, weight and age matched subjects were studied; using Auto Spiro AS 300 spirometer for ventilatory parameters and NOVA stat profile 3 analyser for gas analysis. Each subject performed a progressive incremental treadmill exercise by Bruce protocol to their symptom limited maximum. Minute ventilation (VE), tidal volume (VT) and frequency of respiration (f) increased significantly (P<0.001). Acidosis occured following exercise as pH of arterialized venous blood declined significantly (P<0.05). Gas analysis of arterialized venous blood showed a rise in pO2 (P<0.001) and a fall in pCO2 (P<0.001). Recovery of acid base status as well as gaseous pressure in blood did not occur after 10 min. Expired gas pCO2 declined significantly (P<0.05) and pO2 increase significantly (P<0.05). These pressures returned to resting levels 10 min after exercise. Thus in normal young adults heavy exercise caused an increment in ventilatory kinetics producing hyperpnoea which recovers after a rest of 10 min. Acidosis stimulates the respiratory centre to cause hyperventilation which tries to meet the added metabolic demands of strenuous exercise.

An analysis of surgical complications; a tool to improve surgical outcome.

Complications in surgery are an important cause of morbidity and mortality. Complications may result in an increased length of stay in hospital, repeat surgery, additional medical treatment, legal issues and increased costs. Classification and regular audit of complications is a useful tool to improve patient safety and surgical outcome. The purpose of this study is to identify and classify surgical complications and evaluate the various contributing factors. The complications were categorized by Clavein Dindo system as Grade 1:52 (29.1%), Grade II :45 (25.1%),Grade IIIa:26 (14.5%), Grade IIIB:25 (14%), Grade IVa:5 (2.8%), Grade IVb:0 and Grade V:26 (14.5%) . The complication rate was 5.3% and mortality rate was 0.8% in total 3336 surgical procedures. There was significantly higher mortality in complications due to patient related factors 23.4% (11/47), compared to technical factors 4.2% (2/48) and other factors 15.4% (13/84) (p value = 0.024). The mortality was significantly higher in the patients who required ICU care, 54% (20/37), in class B surgical procedures 22.4% (22/98) and those who developed complications after emergency procedures were 31% (14/45). The mortality was significantly higher in the patients who required medical intervention for various medical complications 30.1% (19/63) compared to those who required surgical intervention 8.4% (5/59) or were managed conservatively 3.5% (2/57) (p value = 0.0001).

Stapled haemorrhoidectomy in the operative treatment of grade III and IV haemorrhoids.

Stapled haemorrhoidectomy (SH) is a minimally invasive intervention that uses a stapling device which avoids the need for wounds in the sensitive anal area and reduces the pain after surgery. This study was undertaken in Nepal Medical College Teaching Hospital from January 2010 to December 2012 to evaluate the efficacy of this modality of treatment among patients (32) who presented in the Surgery OPD with grade III and grade IV haemorrhoids. The results of SH were evaluated by the relief of symptoms, severity of post operative pain, and complications of SH. Twenty five (78.1%) patients had grade III and 7 (21.9%) presented with grade IV hemorrhoids. The most frequent presentation reported in our study was bleeding per rectum with perianal prolapse. Mean operating time was 40-60 minutes whereas mean hospital stay was 1.9 days. Urinary retention was the most common complication found in 12 (37.5%) patients in the immediate post operative period. SH is a safe, rapid, and convenient surgical remedy for grade III and grade IV hemorrhoids with low rate of complications, minimal postoperative pain, and shorter hospital stay.

Ghrelin receptor regulates HFCS-induced adipose inflammation and insulin resistance.

BACKGROUND AND OBJECTIVES: High fructose corn syrup (HFCS) is the most commonly used sweetener in the United States. Some studies show that HFCS consumption correlates with obesity and insulin resistance, while other studies are in disagreement. Owing to conflicting and insufficient scientific evidence, the safety of HFCS consumption remains controversial. SUBJECTS/METHODS: We investigated the metabolic consequences of mice fed a (a) regular diet, (b) 'Western' high-fat diet or (c) regular diet supplemented with 8% HFCS in drinking water (to mimic soft drinks) for 10 months. Adipose tissue macrophages (ATMs) have emerged as a major pathogenic factor for obesity and insulin resistance. ATMs consist of proinflammatory F4/80(+)CD11c(+) macrophages and anti-inflammatory F4/80(+)CD11c(-) macrophages. In this study, we assessed the effects of HFCS on ATMs in intra-abdominal fat. RESULTS: We found that HFCS feeding in mice induced more severe adipose inflammation and insulin resistance than even the higher-calorie-containing 'Western' high-fat diet, and these HFCS-induced deleterious effects were independent of calorie intake or body fat content. We showed that similar to 'Western' high-fat diet, HFCS triggered a robust increase of both proinflammatory ATMs and anti-inflammatory ATMs in intra-abdominal fat. Remarkably, however, the anti-inflammatory ATMs were much less abundant in HFCS-fed mice than in high-fat-fed mice. Furthermore, we showed that deletion of the ghrelin receptor (growth hormone secretagogue receptor, GHS-R) ameliorates HFCS-induced adipose inflammation and insulin resistance. HFCS-fed GHS-R-null mice exhibit decreased proinflammatory ATMs in intra-abdominal fat, reduced adipose inflammation and attenuated liver steatosis. CONCLUSION: Our studies demonstrate that HFCS has detrimental effects on metabolism, suggesting that dietary guidelines on HFCS consumption for Americans may need to be revisited. GHS-R deletion mitigates the effects of HFCS on adipose inflammation and insulin resistance, suggesting that GHS-R antagonists may represent a novel therapy for insulin resistance.

Study on responses after splenectomy for idiopathic thrombocytopenic purpura patients, Kathmandu, Nepal.

Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder characterized by accelerated destruction of platelets due to the presence of platelet (Plt) auto antibodies and impaired production of platelets. Splenectomy is still the standard salvage therapy in cases refractory to corticosteroid therapy. Retrospectively we analyzed 34 patients with ITP that underwent splenectomy in the period May 2010 to March 2012 and have been followed for at least 12 months. All patients met the diagnostic criteria for ITP. The median age at diagnosis was 26 years (range: 14-55 years). Overall response rate to splenectomy after 1 year of follow up was 94.1%, with Complete response in 32 and no response or relapse in 2 (5.8%). Sex didn't influence the outcome after splenectomy in our group of patients. Only preoperative response to steroids (P value = 0.018) and post-operative platelet count (P value = 0.013) were found to be significant statistically. Splenectomy considered as safe and effective treatment for patients with ITP who failed to respond to firs-line treatment with corticosteroids. Management of patients who do not respond or relapse after splenectomy represent an important problem for further treatment due to low response rate to other treatment options.