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In order to improve the understanding of the dynamical deformation processes of sea ice in the seasonal ice zone (SIZ), measures to detect deformed ice were developed and validated using satellite L-band synthetic aperture radar (ScanSAR) images for the southern Sea of Okhotsk. To approach, sea ice was categorized into three ice types, typical of the sea ice in this region: nilas (thin level), pancake ice (thin rough), and deformed ice (thick rough), and then the measures to classify into these categories were developed using ALOS/Phased Array type L-band Synthetic Aperture Radar (PALSAR) as a function of backscatter coefficients at HH polarization ( $\sigma _{\text {HH}}^{0}$ ) and incidence angle ( $\theta _{i}$ ), based on the field observations. Comparative analysis confirmed that PALSAR can detect deformed ice more efficiently than RADARSAT-2 (C-band SAR). The temporal evolution of the area, judged as deformed ice from these measures, shows significant variability with both time and space, and deformed ice regions appear in relatively linear alignments with a width of a few tens of kilometers in the inner ice pack region, consistent with ice drift convergence. To confirm the results, PALSAR-2 images at HH and HV polarizations were examined as a function of $\theta _{i}$ , based on the four-year field observations in the same area. The results revealed that $\sigma _{\text {HH}}^{0}$ and $\sigma _{\text{HV}}^{0}$ are both subject to floe sizes as well as deformed ice, and $\sigma _{\text{HV}}^{0}$ is more sensitive. This indicates that care should be taken when applying these measures to the ice areas where significantly small floes are dominant like the marginal ice zone.

A 32-year-old man presented with complete third nerve palsy. Brain magnetic resonance imaging revealed a possible sporadic oculomotor nerve schwannoma in the left cavernous sinus. Interestingly, the patient’s ptosis was fluctuating and eased immediately after application of ice over his eyelid. The ice pack test (IPT) is a simple and fast method that can help diagnose myasthenia gravis (MG) in patients with ptosis. Additional diagnostic investigations (antibody assays and repetitive stimulation) excluded associated MG in the patient. Tumor treatment with Gamma Knife radiosurgery was planned. This case highlights the finding that IPT can also be positive in neurogenic (non-myasthenic) ptosis, but its usefulness in other disorders associated with muscle weakness and fatigability remains questionable.

Milk fat trans-10 C18:1 can be used in diagnosing low milk fat production on dairy farms because it is a specific marker of biohydrogenation-induced milk fat depression. Individual fatty acids (FA), including the trans C18:1 isomer, can be determined only by gas-liquid chromatography. The analysis is currently available at a limited number of laboratories and often requires long-distance shipping. Expedited shipping with dry ice or ice packs is expensive. Therefore, the objective of this study was to determine the effect of heat treatment before shipping, shipping temperature, and shipping time on milk FA profile. Samples were collected from 3 farms on 2 occasions and stored in a polystyrene foam cooler with an ice pack, at room temperature, or at 37°C for 1, 2, 3, and 7 d. Heating the sample before shipping, shipping temperature, and shipping time had very little effect on any FA analyzed. Differences observed were of small magnitude and not of practical importance, demonstrating that milk FA profile is expected to be very stable during shipping. Based on this, we propose that freezing samples and shipping in a sealed bag by second-day shipment is appropriate and demonstrated that this had little effect on FA profile of 48 milk samples. Importantly, these methods are recommended only for gas-liquid chromatography analysis of FA profile. Freezing is not appropriate for shipping for analysis by mid-infrared spectrometry-based methods or methods quantifying compounds per unit of milk because it is difficult to homogenize samples after freezing or extended shipping that results in denaturization of proteins and breaking of fat globules.

Poly- and perfluoroalkyl substances are synthetic chemicals that are widely present in the global environment including the Arctic. However, little is known about how these chemicals (particularly perfluoroalkyl acids, PFAA) enter the Arctic marine system and cycle between seawater and sea ice compartments. To evaluate this, we analyzed sea ice, snow, melt ponds, and near-surface seawater at two ice-covered stations located north of the Barents Sea (81 °N) with the aim of investigating PFAA dynamics in the late-season ice pack. Sea ice showed high concentrations of PFAA particularly at the surface with snow-ice (the uppermost sea ice layer strongly influenced by snow) comprising 26–62% of the total PFAA burden. Low salinities (, Sea ice accumulates perfluoroalkyl acids (PFAAs) from seawater and from atmospheric deposition in snow. Subsequent melting of surface ice layers through seasonal changes later results in high PFAA concentrations in the under-ice seawater.

Context: Athletes in combat sports who have sustained facial hematomas during competition have traditionally been treated with an enswell. These treatments take place between rounds of the competition and generally last less than 60 seconds. The efficacy of this modality has not been studied. Other modalities may provide a more effective cryotherapy treatment in this timeframe. Objective: To compare the efficacy of different forms of rapid cryotherapy to cause surface temperature changes of the face within 60 seconds of application. Design: Crossover study. Setting: Laboratory. Participants: Eleven healthy men (age 21.73 [1.42] y, mass 82.1 [5.6] kg, height 177.2 [7.0] cm). Interventions: A 60-second treatment using chilled surgical steel enswell, copper, commercial cold pack, aluminum, brass, ice cube, ice pack, and saltwater pack. Main Outcome Measures: Preintervention and postintervention surface facial temperatures. Results: The ice bag, cold pack, ice cube, saltwater pack, and stainless-steel enswell caused statistically different temperatures preintervention to postintervention. The ice bag and saltwater pack cause statistically greater cooling than the other materials tested. Conclusions: This study does not support the clinical use of an enswell to provide short-duration cryotherapy treatments to facial tissue, as ice packs are more effective.

Background. Total knee arthroplasty (TKA) is a well-established procedure for end-stage arthritis of the knee with complications such as swelling and pain. The aim of this study is to estimate the effect of mirabilite with ice pack versus ice pack in relieving pain, swelling, range of motion (ROM), and serum CRP level on patients after TKA. Methods. Eighty patients undergoing primary unilateral TKA were randomly assigned to two groups (MIP group and WIP group). We used VAS to measure knee pain at 24 h, 48 h, and 72 h after the surgery, respectively. Knee swelling degree was evaluated by measuring the girth of the leg at the center of the patella and 10 cm above and below it at the same frequency. The active ROM of the knee was measured by using a universal goniometer of plastic material at 72 h postoperatively. The serum CRP level was also measured at 72 h postoperatively. Results. The MIP group showed statistically significant lower knee girth at 48 h ( p < 0.05 ) and 72 h ( p < 0.05 ) postoperatively and VAS score at 72 h ( p = 0.018 ) postoperatively after TKA than the WIP group. The ROM of the MIP group was significantly wider than the WIP group ( p = 0.024 ). The CRP level ( p = 0.036 ) and length of stay (LOS) ( p = 0.037 ) of the MIP group were significantly lower than the WIP group. Conclusion. Mirabilite with ice pack after TKA showed superiority in relieving pain, reducing swelling, and improving ROM than ice pack only.

The radiative transfer of shortwave solar radiation through the sea ice cover of the polar oceans is a crucial aspect of energy partitioning at the atmosphere–ice–ocean interface. A detailed understanding of how sunlight is reflected and transmitted by the sea ice cover is needed for an accurate representation of critical processes in climate and ecosystem models, such as the ice–albedo feedback. Due to the challenges associated with ice internal measurements, most information about radiative transfer in sea ice has been gained by optical measurements above and below the sea ice. To improve our understanding of radiative transfer processes within the ice itself, we developed a new kind of instrument equipped with a number of multispectral light sensors that can be frozen into the ice. A first prototype consisting of a 2.3 m long chain of 48 sideward planar irradiance sensors with a vertical spacing of 0.05 m was deployed at the geographic North Pole in late August 2018, providing autonomous, vertically resolved light measurements within the ice cover during the autumn season. Here we present the first results of this instrument, discuss the advantages and application of the prototype, and provide first new insights into the spatiotemporal aspect of radiative transfer within the sea ice itself. In particular, we investigate how measured attenuation coefficients relate to the optical properties of the ice pack and show that sideward planar irradiance measurements are equivalent to measurements of total scalar irradiance.

Background: Chest tube causes severe pain during removal because it attaches to the endothelium in the chest cavity. Objectives: This study aimed to determine the effectiveness of cold application with ice pack and gel pad in the control of pain experienced during chest tube removal. Methods: The sample of prospective, parallel three-arm (1:1:1), randomized controlled clinical trial consisted of 180 patients in two experimental groups (ice pack/gel pad) and one control group. The primary outcome was effect of cold application materi- als on severity of pain during chest removal. Secondary outcomes were duration of cold application and analgesic requirements of the patients. Results: The study found that the cold application using either of the materials reduced the severity of pain and the need for analgesics after the removal of chest tube compared to the control group (p

Aim: The aim of this study was to evaluate the efficacy of ice pack therapy on pain after mandibular third molar extraction. Material and methods: Thirty patients who required extraction of mandibular third molars and satisfied the inclusion criteria were included in the study. Bilateral full erupted mandibular third molars were extracted under local anesthesia. Routine medication and ice pack therapy (directly over the masseteric region of the surgery region for 12 hours, intermittently for 20 minutes) were performed after one side mandibular third molar extraction and only routine medication was applied after other side mandibular third molar extraction. The pain was evaluated with Visual Analog Scale. The Student t-test was applied to compare pain levels between groups. Results: The study was carried out in 30 patients, 15 female and 15 male with a mean age of 21.53±2.22 years. There was a statistically significant difference in the evaluation of VAS levels in postoperative 4, 6, 8, 12, 24 hours between the groups. Pain levels of female were found to be higher than male at 2nd, 4th, 6th and 24th hours in the non-ice pack therapy group and found to be higher than male at 4th, 6th and 8th hours in the ice pack therapy group. Conclusion: Pain levels after mandibular third molar extraction were significantly lower who had an ice pack therapy. Ice pack therapy is a viable alternative mode of improving the quality of life of patients after the extraction of third molars.

Airborne electromagnetic induction sensors have demonstrated their extensive capacities to measure sea-ice thickness distributions. However, biases can emerge when comparing these 1-D measurements to a broader 2-D regional scale due to the spatial anisotropy inherent to sea-ice cover. Automated processing of available sea-ice maps could significantly ease the decision on how to set up an optimised flight pattern, which would result in representative ice thickness numbers for the region. In this study, first we investigate the extent to which the sea-ice anisotropy can influence the representativeness of an airborne survey compared to the regional situation. Second, we propose a method to process sea-ice maps prior to flights to help preparing the most representative flight plan possible for the local area. The method is based on automated segmentation of radar satellite images and extensive simulation of flight transects over the image. The spatial analysis of these transects enables for the identification of the most representative survey trajectories for the area. The method was applied for seven different synthetic aperture radar satellite images over Arctic sea ice north of Svalbard. The results indicate that the proposed method improved the representativeness of the airborne survey by identifying the most suitable transect over the ice pack.

A new passive microwave remote sensing technique, wideband autocorrelation radiometry (WiBAR), directly measures the microwave propagation time difference of multipath microwave emission from low-loss layered surfaces such as a dry snowpack and a freshwater lake icepack. The microwave propagation time difference through the pack yields a measure of its vertical extent. However, the presence of variable pack thicknesses within a footprint of the radiometer’s antenna will add complexity to the retrieved time delay. This issue is more severe for WiBAR on airborne and spaceborne platforms than WiBAR on ground-based platforms since the footprint for a given radiometer antenna is larger. From a simple forward model for a layer having distinct thickness values within one footprint (pixel), the system requirements for resolving these distinct thickness values are derived. A subpixel lake ice thickness distinction of 3.7 cm is demonstrated with an X-band WiBAR instrument at an incidence angle of 70°.

The role of synoptic-scale cyclones in the trends and variability of Arctic sea ice conditions has remained uncertain. In recognition, we conduct a systematic investigation of how sea-ice concentration (SIC) changes with cyclone passage, including all individual storms that pass over any part of the region's ice pack. For all seasons, especially summer and autumn, we find a pattern of higher ice concentration after a region is influenced by a cyclone compared to when it is not, primarily due to thermodynamic effects. During warm months, cyclones appear to slow the general day-to-day decline in concentration; in cold months, cyclones augment the day-to-day increase. These relationships are changing over time, with cyclone-associated concentration changes becoming less distinct from overall changes. Cyclone effects on ice divergence are spatially variable; computed fields are noisy. In summer, these dynamic effects of cyclone passage generally decrease SIC, but are outweighed by the thermodynamic effects (e.g., reductions in air temperature, shortwave radiation). In autumn, cyclone-associated concentration changes are not as easily explained by observed cyclone conditions. Key questions remain regarding the extent to which our findings are influenced by artifacts of surface melt and weather effects on the passive microwave retrievals.

Leads are a key feature of the Arctic ice pack during the winter owing to their substantial contribution to the surface energy balance. According to the present understanding, enhanced heat and moisture fluxes from high lead concentrations tend to produce more boundary layer clouds. However, described here in our composite analyses of diverse surface- and satellite-based observations, we find that abundant boundary layer clouds are associated with low lead flux periods, while fewer boundary layer clouds are observed for high lead flux periods. Motivated by these counterintuitive results, we conducted three-dimensional cloud-resolving simulations to investigate the underlying physics. We find that newly frozen leads with large sensible heat flux but low latent heat flux tend to dissipate low clouds. This finding indicates that the observed high lead fractions likely consist of mostly newly frozen leads that reduce any pre-existing low-level cloudiness, which in turn decreases downwelling infrared flux and accelerates the freezing of sea ice., Cracks in Arctic sea ice (leads) are becoming more prevalent and widespread, yet studies regarding their impacts on clouds are limited. Here, contrary to the present understanding, diverse observations and modelling simulations show that higher leads concentrations do not necessarily result in more low clouds.

OBJECTIVES: Digital nerve block is a painful procedure. Several methods have been proposed to decrease the injection pain. Applying an ice pack is a pertinent choice due to its effectiveness on pain reduction, convenience, and low costs. In this study, the degree of injection pain reduction was assessed after applying an ice pack to the site of anesthetic injection. METHODS: One hundred participants with traumatic finger injury were assessed. Digital nerve block was performed in fifty patients in the intervention group after 6 min of ice application. In the control group, this procedure was done without ice. The primary outcome was the difference between the needle stick and infiltration pain scores with and without ice pack. The secondary outcome the patient satisfaction score. The protocol of this study was approved by the Institutional Review Board, and it is registered in the Iranian Registry of Clinical Trials. RESULTS: The pain score was assessed using a Numeric Rating Scale. Both the needle skin and infiltration pain scores were statistically significantly lower in the intervention group (P < 0.001). The mean and median needle stick pain scores were 1.5 and 1.0 in the intervention group and 6.8 and 7.0 in the control group, respectively. Moreover, the mean and median infiltration pain scores were 2.7 and 2.0 in the intervention group and 8.5 and 9.0 in the control group, respectively. Patient satisfaction score was significantly higher in the intervention group. CONCLUSIONS: Ice pack is inexpensive, readily available, and is easy to apply. We recommend this method to reduce the injection pain before digital nerve block in the emergency department.

We present the generation and validation of an updated version of the TanDEM-X digital elevation model (DEM) of Antarctica: the TanDEM-X PolarDEM 90 m of Antarctica. Improvements compared to the global TanDEM-X DEM version comprise filling gaps with newer bistatic synthetic aperture radar (SAR) acquisitions of the TerraSAR-X and TanDEM-X satellites, interpolation of smaller voids, smoothing of noisy areas, and replacement of frozen or open sea areas with geoid undulations. For the latter, a new semi-automatic editing approach allowed for the delineation of the coastline from DEM and amplitude data. Finally, the DEM was transformed into the cartographic Antarctic Polar Stereographic projection with a homogeneous metric spacing in northing and easting of 90 m. As X-band SAR penetrates the snow and ice pack by several meters, a new concept for absolute height adjustment was set up that relies on areas with stable penetration conditions and on ICESat (Ice, Cloud, and land Elevation Satellite) elevations. After DEM generation and editing, a sophisticated height error characterization of the whole Antarctic continent with ICESat data was carried out, and a validation over blue ice achieved a mean vertical height error of just −0.3 m ± 2.5 m standard deviation. The filled and edited Antarctic TanDEM-X PolarDEM 90 m is outstanding due to its accuracy, homogeneity, and coverage completeness. It is freely available for scientific purposes and provides a high-resolution data set as basis for polar research, such as ice velocity, mass balance estimation, or orthorectification.

Background and objectives: vaccine injections are a common cause of iatrogenic pain and anxiety, contributing to non-compliance with scheduled vaccinations. With injection-related pain being recognised as a barrier to vaccination uptake in both adults and children, it is important to investigate strategies to effectively reduce immunisation pain. This prospective randomised controlled trial investigated the effects of applying an ice pack on vaccine-related pain in adults. Methods: medical students receiving the flu vaccination were randomised to receive an ice pack (intervention) or placebo cold pack (control) at the injection site for 30 s prior to needle insertion. Immediate post-vaccination pain (VAS) and adverse reactions in the proceeding 24 h were recorded. Results: pain scores between the intervention (n = 19) and control groups (n = 16) were not statistically significant (intervention: median pain VAS = 7.00, IQR = 18, control: median pain VAS = 11, IQR = 14 (p = 0.26). There were no significant differences in the number of adverse events between the two groups (site pain p = 0.18, localised swelling (p = 0.67), bruising p = 0.09, erythema p = 0.46). Discussion: ice did not reduce vaccination-related pain compared to cold packs. COVID-19 related restrictions impacted participant recruitment, rendering the study insufficiently powered to draw conclusions about the results.

Background: Bruising is one of the most common adverse events following administration of enoxaparin sodium, which can lead to unpleasant consequences such as reduced access to various sites for injection, reduced satisfaction of patients from treatment and care provided. Cold application is helpful for better management of these side effects which could be easily accessible and economical for the patients. Cold application appears to be cheaper and easily available. Aim: The purpose of this study was to identify the effectiveness of ice pack application on level of pain and bruise formation among patients receiving subcutaneous low molecular weight heparin. Method: Quasi experimental nonequivalent control group posttest only design was adopted. The population comprised of 60 patients receiving subcutaneous low molecular weight heparin from selected hospitals of Pune. Sample of the study were 60 patients receiving subcutaneous low molecular weight heparin patients selected by convenient sampling. The patients in experimental group were provided with ice pack application before receiving subcutaneous low molecular weight heparin to reduce the level of pain and bruise formation. Data was collected by using numerical pain scale, visual analog scale and transparent ruler scale. Result: The study findings showed that average numerical pain score in experimental group was 3.87 and 6.33 in control group. Bruise size was measured in cm. In experimental group Average bruise formation size was 0.0233 after 24 hours of injection, 0.1633 after 48 hours of injection and 0.1766 after 72 hours of injection compared to control group 0.2733 after 24 hours of injection, 0.3933 after 48 hours of injection and 0.4066 after 72 hours of injection. There is significant difference in mean scores of experimental and control group. Conclusion: The findings of the study shows that the ice pack application is effective in reducing the level of pain and bruise formation among patients receiving subcutaneous low molecular weight heparin.

Recent studies pointed to a high ice nucleating activity (INA) in the Arctic sea surface microlayer (SML). However, related chemical information is still sparse. In the present study, INA and free glucose concentrations were quantified in Arctic SML and bulk water samples from the marginal ice zone, the ice-free ocean, melt ponds, and open waters within the ice pack. T50 (defining INA) ranged from -17.4 to -26.8 °C. Glucose concentrations varied from 0.6 to 51 μg/L with highest values in the SML from the marginal ice zone and melt ponds (median 16.3 and 13.5 μg/L) and lower values in the SML from the ice pack and the ice-free ocean (median 3.9 and 4.0 μg/L). Enrichment factors between the SML and the bulk ranged from 0.4 to 17. A positive correlation was observed between free glucose concentration and INA in Arctic water samples (T50(°C) = (-25.6 ± 0.6) + (0.15 ± 0.04)·Glucose(μg/L), RP = 0.66, n = 74). Clustering water samples based on phytoplankton pigment composition resulted in robust but different correlations within the four clusters (RP between 0.67 and 0.96), indicating a strong link to phytoplankton-related processes. Since glucose did not show significant INA itself, free glucose may serve as a potential tracer for INA in Arctic water samples.

Recent reports on Arctic underice phytoplankton blooms have directed attention to primary production below the sea ice cover. Such underice blooms cannot be detected from space; thus, methods for autonomous underice measurements are critically needed to extend observations beyond ship-based surveys. One central aspect of the ecology of these blooms is whether they were advected from open-water areas or were able to develop below the ice cover under typically low light conditions. The photoacclimation state of the bloom can provide clues about the growth conditions and therefore its origin. Here we investigate the photoacclimation state of a Phaeocystis pouchetii-dominated underice bloom in the Arctic Ocean using ratios of photoprotective carotenoids (PPC) to photosynthetic carotenoids (PSC) and chlorophyll a. The pigment proxies indicate local growth under the ice pack. Furthermore, a method using in situ light absorption measurements to estimate the PPC:PSC ratio was in agreement with the pigment data. The slope of in situ phytoplankton absorption between 488 and 532nm, affected by both PPC and PSC, had a significant linear relationship to the PPC:PSC ratio, indicating that prediction of photoacclimation state can be obtained from absorption profiles. We also review, with regard to the pigment function, different ways of grouping pigments into PPC or PSC applied in previous studies. Although more validation data sets are needed to assess the impact of pigment packaging on the relationship between PPC:PSC and absorption measurement slopes, our study shows the potential for using in situ absorption measurements to collect information about phytoplankton physiology below sea ice. Plain Language Summary Phytoplankton blooms below sea ice cover, that is, underice blooms, can be advected by ocean currents below the ice pack from ice-free waters where they had sufficient light available for growth. They can also grow below the ice pack if sufficient light is transmitted through the ice, and they are able to adjust to the typically low light conditions. Algal pigments can indicate which of the two scenarios is more likely. Algal pigments capture sunlight for photosynthesis, but some of them are used to protect the algal cells from excess light. The ratio of photoprotective to photosynthetic pigments reveals the photoacclimation state ("short time adjustments") of the algae. In this study we investigate the photoacclimation state of an Arctic underice bloom based on pigment ratios, which indicate local growth below the ice pack. Furthermore, we validate a method to estimate the pigment ratios from light absorption measurements carried out with an instrument in the water column. Studies like these are important for developing methods to study remote areas. Ship-based surveys can only cover a restricted area, and satellite remote sensing does not provide biological information from ice-covered waters. Our study shows promising results for using water column instruments to study phytoplankton physiology.

Continuing losses of multi-year sea ice (MYI) across the Arctic are causing first-year sea ice (FYI) to dominate the Arctic ice pack. Melting FYI provides a strong seasonal pulse of dissolved organic matter (DOM) into surface waters; however, the biological impact of this DOM input is unknown. Here we show that DOM additions cause important and contrasting changes in under-ice bacterioplankton abundance, production and species composition. Utilization of DOM was influenced by molecular size, with 10–100 kDa and >100 kDa DOM fractions promoting rapid growth of particular taxa, while uptake of sulfur and nitrogen-rich low molecular weight organic compounds shifted bacterial community composition. These results demonstrate the ecological impacts of DOM released from melting FYI, with wide-ranging consequences for the cycling of organic matter across regions of the Arctic Ocean transitioning from multi-year to seasonal sea ice as the climate continues to warm. Arctic sea-ice melt causes a release of dissolved organic material (DOM) into the surface waters. The increased dominance of first-year ice and DOM release is impacting under-ice bacterial communities.

The diminishing Arctic sea ice pack has been widely studied, but previous research has mostly focused on time-mean changes in sea ice rather than on short-term variations that also have important physical and societal consequences. In this study we test the hypothesis that future interannual Arctic sea ice area variability will increase by utilizing 40 independent simulations from the Community Earth System Model's Large Ensemble (CESM-LE) for the 1920–2100 period and augment this with simulations from 12 models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5). Both CESM-LE and CMIP5 models project that ice area variability will indeed grow substantially but not monotonically in every month. There is also a strong seasonal dependence in the magnitude and timing of future variability increases that is robust among CESM ensemble members. The variability generally correlates with the average ice retreat rate, before there is an eventual disappearance in both terms as the ice pack becomes seasonal in summer and autumn by late century. The peak in variability correlates best with the total area of ice between 0.2 and 0.6 m monthly thickness, indicating that substantial future thinning of the ice pack is required before variability maximizes. Within this range, the most favorable thickness for high areal variability depends on the season, especially whether ice growth or ice retreat processes dominate. Our findings suggest that thermodynamic melting (top, bottom, lateral) and growth (frazil, congelation) processes are more important than dynamical mechanisms, namely ice export and ridging, in controlling ice area variability.

The ice arches that usually develop at the northern and southern ends of Nares Strait play an important role in modulating the export of Arctic Ocean multi-year sea ice. The Arctic Ocean is evolving towards an ice pack that is younger, thinner, and more mobile and the fate of its multi-year ice is becoming of increasing interest. Here, we use sea ice motion retrievals from Sentinel-1 imagery to report on the recent behavior of these ice arches and the associated ice fluxes. We show that the duration of arch formation has decreased over the past 20 years, while the ice area and volume fluxes along Nares Strait have both increased. These results suggest that a transition is underway towards a state where the formation of these arches will become atypical with a concomitant increase in the export of multi-year ice accelerating the transition towards a younger and thinner Arctic ice pack., Ice arches that form along Nares Strait, which separates Greenland and Ellesmere Island, act to reduce the export of thick multi-year ice out of the Arctic. Here, we show that there has been a recent trend towards shorter duration arch formation that has resulted in enhanced transport of ice along the strait.

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We thank Dr. Silvestri for the comment on our article1 and agree that a relatively high proportion of patients showed discordant results between the ice pack test and single-fiber electromyography (SF-EMG) because they were observed in 15% of patients with a final diagnosis of ocular myasthenia (OM). Most of discordant cases were related to the negativity of the ice pack test in the presence of an altered SF-EMG result. One explanation could be the lack of repetition of the ice pack test, as we outlined in the discussion. Indeed, a previous study showed that repeated ice pack tests improved sensitivity by 34.6% compared with a single test.2 We also found that the repetition of the ice pack test in some patients increased its sensitivity and, therefore, the number of patients showing concordant results (unpublished data).

The Earth’s climate is rapidly changing and some of the most drastic changes can be seen in the Arctic, where sea ice extent has diminished considerably in recent years. As the Arctic climate continues to change, gathering in situ sea ice measurements is increasingly important for understanding the complex evolution of the Arctic ice pack. To date, observations of ice stresses in the Arctic have been spatially and temporally sparse. We propose a measurement framework that would instrument existing sea ice buoys with strain gauges. This measurement framework uses a Bayesian inference approach to infer ice loads acting on the buoy from a set of strain gauge measurements. To test our framework, strain measurements were collected from an experiment where a buoy was frozen into ice that was subsequently compressed to simulate convergent sea ice conditions. A linear elastic finite element model was used to describe the response of the deformable buoy to mechanical loading, allowing us to link the observed strain on the buoy interior to the applied load on the buoy exterior. The approach presented in this paper presents an instrumentation framework that could use existing buoy platforms as in situ sensors of internal stresses in the ice pack.

Introduction: Radial Arterial Puncture (AP) is much needed procedure in critical care setting but pain associated during AP makes patients anxious and stressed. Aim: To evaluate the efficacy of ethyl chloride spray versus ice pack application in decreasing pain during puncture of radial artery for Arterial Blood Gas (ABG) analysis. Materials and Methods: A randomised controlled parallel group design study was conducted in a tertiary care hospital in critical care units among 60 participants during November 2018 to December 2018. Seventy-two participants were initially recruited for this study who had to undergo ABG analysis out of them 12 were excluded and finally 60 participants were randomly allocated to ethyl chloride spray group (n=30) and ice pack application group (n=30). The assigned treatment was given just prior to radial AP. The primary outcome variable was to assess the level of pain score, which participants experienced during AP and measured by pain numerical rating scale while secondary outcome variable was incidence of haematoma within two hours after procedure. Data were presented in frequency, percentages, chi-square, Mann-Whitney U and Fisher’s-exact test. The statistical computer package, IBM Statistical Package for the Social Sciences (SPSS 23.0) was used for statistical analysis. Results: The mean pain score was 2.5±1.2 in the ethyl chloride group and 3.1±1.8 in ice pack application group (p=0.113); while incidence of haematoma was significantly high in ice pack application group as compared to ethyl chloride group (33.3% vs. 6.66%; p=0.01). Conclusion: Ethyl chloride spray and ice pack application have no significant difference in reducing pain intensity due to radial AP

A number of feedbacks regulate the response of Arctic sea ice to local atmospheric warming. Using a realistic coupled ocean‐sea ice model and its adjoint, we isolate a mechanism by which significant ice growth at the end of the melt season may occur as a lagged response to Arctic atmospheric warming. A series of perturbation simulations informed by adjoint model‐derived sensitivity patterns reveal the enhanced ice growth to be accompanied by a reduction of snow thickness on the ice pack. Detailed analysis of ocean‐ice‐snow heat budgets confirms the essential role of the reduced snow thickness for persistence and delayed overshoot of ice growth. The underlying mechanism is a snow‐melt‐conductivity feedback, wherein atmosphere‐driven snow melt leads to a larger conductive ocean heat loss through the overlying ice layer. Our results highlight the need for accurate observations of snow thickness to constrain climate models and to initialize sea ice forecasts., Key Points Arctic sea ice sensitivity to atmospheric warming is computed using a numerical adjoint, revealing warming can lead to lagged sea ice growthSnow melt—in response to early warming—is the key preconditioner, enabling large conductive ocean heat loss to support lagged ice growth